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C00017 00005	.S INTRODUCTION
C00023 00006	.S ARTIFICIAL INTELLIGENCE PROJECT
C00030 00007	.SS Robotics
C00041 00008	.SSS Vision
C00053 00009	.begin bib
C00063 00010	.ss Theoretical Studies
C00079 00011	.begin bib aimer
C00088 00012	.sss Representation Theory
C00097 00013	.sss Grammatical Inference
C00101 00014	.SS Heuristic Programming
C00110 00015	.sss Automatic Program Generation
C00113 00016	.sss Board Games
C00118 00017	.sss Symbolic Computation
C00124 00018	.SS Natural Language
C00132 00019	.begin bib
C00137 00020	.sss Semantics
C00147 00021	.begin bib
C00153 00022	.SS Programming Languages
C00162 00023	.sss FAIL
C00164 00024	.sss SAIL
C00167 00025	.SS Computer Facilities
C00174 00026	.sss Early Development
C00176 00027	.sss Hardware
C00179 00028	.sss Software
C00184 00029	.begin bib once fac indent 0,0
C00190 00030	.SS Associated Projects
C00199 00031	.sss Digital Holography
C00201 00032	.sss Sound Synthesis
C00204 00033	.sss Mars Picture Processing
C00207 00034	.S HEURISTIC PROGRAMMING PROJECT
C00220 00035	.ss Views Expressed by Others Concerning DENDRAL
C00227 00036	.BEGIN BIB
C00241 00037	.APP ACCESS TO DOCUMENTATION
C00249 00038	.APP THESES
C00258 00039	.app FILM REPORTS
C00266 00040	.app EXTERNAL PUBLICATIONS
C00268 00041	Bajcsy, Ruzena, "Computer Description of Textured Scenes", <Proc.
C00274 00042	Cadiou, Jean M., Zohar Manna, "Recursive Definitions of Partial
C00278 00043	Dobrotin, Boris M., Victor D. Scheinman, "Design of a Computer
C00279 00044	Enea, Horace, Kenneth Mark Colby, "Idiolectic Language-Analysis
C00280 00045	Falk, Gilbert, "Scene Analysis Based on Imperfect Edge Data", <Proc.
C00285 00046	Garland, Stephan J., David Luckham, "Translating Recursive Schemes
C00287 00047	Hearn, Anthony, "Computation of Algebraic Properties of Elementary
C00289 00048	Ito, T., "Note on a Class of Statistical Recognition Functions",
C00290 00049	Kahn, Michael, Bernard Roth, "The Near-minimum-time Control of Open-loop
C00293 00050	Lederberg, Joshua, "Hamilton Circuits of Convex Trivalent Polyhedra",
C00296 00051	Manna, Zohar, "Properties of Programs and the First Order
C00305 00052	Nevatia, Ramakant, Thomas O. Binford, "Structured Descriptions
C00306 00053	Paul, Richard, G. Falk, Jerome Feldman, "The Computer
C00308 00054	Quam, Lynn, Robert Tucker, Botond Eross, J. Veverka and Carl
C00309 00055	Reddy, D. Raj., "Segmentation of Speech Sounds", <J. Acoust. Soc.
C00311 00056	Sagan, Carl, J. Lederberg, E. Levinthal, L. Quam, R. Tucker, et al,
C00317 00057	Tenenbaum, Jay, et al, "A Laboratory for Hand-eye Research",
C00318 00058	Waterman, Donald, "Generalization Learning Techniques for Automating
C00320 00059	Yakimovsky, Yoram, Jerome A. Feldman, "A Semantics-Based
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%4Stanford Artificial Intelligence Laboratory →July 1973
Memo AIM-228

Computer Science Department
Report No. STAN-CS-74-409

.CENTER SKIP 2
%5FINAL REPORT

%4The First Ten Years of Artificial Intelligence Research at Stanford

Edited by
Lester Earnest

ARTIFICIAL INTELLIGENCE PROJECT
John McCarthy, Principal Investigator

HEURISTIC PROGRAMMING PROJECT
Edward Feigenbaum and Joshua Lederberg,
Co-principal Investigators

. ⊃

.titles


Sponsored by
ADVANCED RESEARCH PROJECTS AGENCY
ARPA Order No. 457



COMPUTER SCIENCE DEPARTMENT
Stanford University

.next page
.titles




%3ABSTRACT
.FILL ADJUST COMPACT
%1The first  ten  years of  research in  artificial intelligence  and
related  fields  at  Stanford  University  have  yielded  significant
results  in computer  vision  and  control  of  manipulators,  speech
recognition,    heuristic    programming,   representation    theory,
mathematical  theory of computation, and modeling of organic chemical
processes.  This  report summarizes the accomplishments  and provides
bibliographies in each research area.
.skip 2
%2This  research was  supported  by  the Advanced  Research  Projects
Agency of the  Department of Defense under Contract SD-183.  The views
and conclusions contained in this  document are those of the  authors
and  should  not  be  interpreted  as  necessarily  representing  the
official  policies,  either  expressed or  implied,  of  the Advanced
Research Projects Agency or the U. S. Government.%1
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.S INTRODUCTION

Artificial  Intelligence is the experimental and theoretical study of
perceptual and intellectual processes using computers.  Its  ultimate
goal  is to understand these processes well enough to make a computer
perceive, understand and act in ways now only  possible  for  humans.

In the late 1950s John McCarthy and Marvin Minsky organized the Artificial
Intelligence Project at M.I.T.  That activity and another at Carnegie Tech
(now Carnegie-Mellon University) did much of the pioneering research in
artificial intelligence.

In 1962, McCarthy came to Stanford University and initiated another
A. I. Project here.
He obtained financial support for a small activity (6 persons) from the
Advanced Research Projects Agency (ARPA) beginning June 15, 1963.

A Computer Science Department was formed at Stanford in January 1965.  
By that time there were 15 people on the Project, including Edward Feigenbaum
who had just arrived.  Shortly, a decision was made to expand the activities
of the Project, especially in the area of hand-eye research.  Additional
support was obtained from ARPA and a PDP-6 computer system was ordered.  
Lester Earnest arrived in late 1965 to handle administrative responsibilities
of the expanding Project.

By the summer of 1966, the Project had outgrown available campus space
and moved to the D. C. Power Laboratory in the foothills above Stanford.  
The new computer system was delivered there.  Arthur Samuel and Jerome Feldman
arrived at about this time and D. Raj. Reddy joined the faculty, having
completed his doctorate on speech recognition as a member of the Project.  
Several faculty members from other departments affiliated themselves with
the Project, but without direct financial support:  Joshua Lederberg
(Genetics), John Chowning and Leland Smith
(Music), and Anthony Hearn (Physics).

By early 1968, there were just over 100 people on the Project, about
half supported by ARPA.
Kenneth Colby and his group joined the Project that year, with separate
funding from the National Institute of Mental Health.  Other activities
subsequently received some support from the National Science Foundation
and the National Aeronautics and Space Administration.
Zohar Manna joined the Faculty and the Project, continuing his
work in mathematical theory of computation.

In June 1973, the Artificial Intelligence Laboratory (as it is now called)
had 128 members, with about two-thirds at least partially ARPA-supported.
Other Computer Science Faculty members who have received
such support include Robert Floyd, Cordell Green, and Donald Knuth.

The Heuristic Dendral Project (later changed to Heuristic Programming)
was formed in 1965
under the leadership of Edward Feigenbaum and Joshua Lederberg.  It was
initially an element of the A. I. Project and consisted of five or so
people for several years.

The Heuristic Dendral Project became a separate organizational
entity with its own ARPA budget in January 1970 and also obtained some
support from the Department of Health, Education, and Welfare.
It has had 15 to 20 members in recent months.

The following sections summarize accomplishments of the first 10 years (1963-1973).
Appendices
list external publications, theses, film reports, and abstracts of research
reports produced by our staff.
.S ARTIFICIAL INTELLIGENCE PROJECT

The work of the Stanford Artificial Intelligence Project has
been basic and applied research in artificial intelligence and closely
related fields, including computer
vision, speech recognition, mathematical theory of computation, and
control of an artificial arm.

Expenditures from ARPA funds over the ten years beginning June 15, 1963
have amounted to $9.2 million.  About 43% of this was for personnel (salaries,
wages, benefits), 26% for computer and peripheral equipment (purchase, replacement
parts, and rental), 8% for other operating expenses, and 23% for indirect costs.

Here is a short list of what we consider to have been our main accomplishments.
More complete discussions and bibliographies follow.

.cb Robotics

Development of vision programs for finding, identifying and describing
various kinds of objects in three dimensional scenes.  The scenes include objects with flat
faces and also curved objects.

 The development of programs for manipulation and assembly of
objects from parts.  The latest result is the complete assembly of an automobile
water pump.

.cb Speech Recognition

 Development of a system for recognition of continuous speech, later transferred
to Carnegie-Mellon University and now being expanded upon elsewhere.

.cb Heuristic Programming

Our support of Hearn's work on symbolic computation led to the development
of REDUCE, now being extended at the University of Utah and widely used
elsewhere.

 Work in heuristic programming resulting in Luckham's resolution
theorem prover.  This is currently about the best theorem prover in existence, and it
puts us in a position to test the limitations of current ideas about
heuristics so we can go beyond them.

.cb Representation Theory

 Work in the theory of how to represent information in a computer
is fundamental for heuristic programming, for language understanding
by computers and for programs that can learn from experience.  Stanford
has been the leader in this field.

.cb Mathematical Theory of Computation

Our work in mathematical theory of computation is aimed at
replacing debugging by computer checking of proofs that programs
meet their specifications.  McCarthy, Milner, Manna, Floyd, Igarashi,
and Luckham
have been among the leaders in developing the relevant mathematical
theory, and the laboratory has developed the first actual proof-checking
programs that can check proofs that actual programs meet their specifications.
In particular, Robin Milner's LCF is a practical proof checker for a revised version
of Dana Scott's logic of computable functions.

.cb Research Facilities

We have developed a laboratory with very good computer and program facilities
and special instrumentation for the above areas, including a
timesharing system with 64 online display terminals.

We developed a mechanical arm well suited to manipulation research.
It is being copied and used by other laboratories.

We designed an efficient display keyboard that has been adopted at several
ARPAnet facilities.  We invented a video switch for display systems that is
being widely copied.

In the course of developing our facilities, we have improved
LISP, developed an extended Algol compiler called SAIL, and created a document
compiler called PUB (used to produce this report).

Our early Teletype-oriented text editor called SOS has become
an industry standard and our new display editor "E" is much better.

We have written utility programs for the PDP-10 and made
numerous improvements to time-sharing systems.  Many of our programs,
particularly LISP, SAIL, and SOS,
are used in dozens of other computer centers.

We designed an advanced central processor that is about 10 times as
fast as our PDP-10.  In support of this work, we developed interactive
design programs for digital logic that have since been adopted by other
research and industrial organizations.

.cb Training

In the 1963-1973 period, 27 members of our staff published Ph.D. theses as
Artificial Intelligence Memos and a number of other graduate students received
direct or indirect support from the A. I. Project.

The following subsections review principal activities, with references
to published articles and reports.

.SS Robotics

The project has produced several substantial accomplishments:
an automatic manipulation system capable of
assembling a water pump,
a laser ranging apparatus,  and  programs  which  form
symbolic descriptions of complex objects.
We  have  now  focused  a  major  effort  on  robotics in industrial
automation.

.SSS Manipulation 
.MANIP: SUB2!

In 1966, we acquired and interfaced a prosthetic arm from Rancho
Los  Amigos  Hospital.  Although it had major mechanical shortcomings,
the software experience was valuable.    A program was written for
point  to  point  control  of arm movements.  Computer servoing was used
from the beginning and has proven much  more  versatile  than conventional analog
servoing.  A simple system that visually located blocks scattered on
a table and sorted them into stacks according to size was operational
by the spring of 1967 [Pingle 1968].

In order to move through crowded workspaces, a program was written to
avoid obstacles while carrying out arm movements [Pieper 1968]. That program was fairly
general but rather slow, since it used a local and not very smart
search technique to inch its way around obstacles.

A  hydraulic  arm was designed and built according to stringent criteria
of speed and strength.  Kahn developed a minimum-time servo scheme, which
is close to a
bang-bang servo [Kahn 1971]. The effect was impressive (even frightening) but hard on the
equipment.

The next arm was designed with software in mind  [Scheinman 1969].  It was
completed   in   December  1970,  and  has  proved  a  good  research
manipulator; several other  groups  have  made  copies.

Arm  control software for the new arm was
split into a small arm-control servo
program, which ran in real time mode on  our  PDP-6  computer,  and  a
trajectory planning program [Paul 1971], written in a higher level language
and running on a timeshared PDPα-10.

The arm servo software contained several new features: a) feedforward
from a Newtonian dynamic model of  the  arm,  including  gravity  and
inertial   forces;  b)  feedback  as  a  critically  damped  harmonic
oscillator including velocity information from tachometers;  c)  trajectory
modification facility in the servo program, which allows considerable
change  from  planned   trajectories   to   accomodate   contingency
conditions.  Compare  this  control  mechanism  with the usual analog
servo; the kinematic  model  and  computer  servo  allow  changes  of
several  orders  of  magnitude  in the equivalent servo constants, to
account for variations in gravity loads and inertial effects.

The  arm  was  designed  so  that  solution  for  joint  angles  from
position and orientation  is  simple and rapid. 
The techniques  apply
to  a  wide  range  of  arms;  thus  our  work  has  significance for
industrial and other robotics applications.

The MOVE_INSTANCE capability [Paul 1971] shows a simple form of  automating  some
manipulation  procedures.     The routine chooses a best grasping and
departure for a class of known objects.  Models of these objects  are
stored  in  order  to choose all possible grasping positions -- parallel
faces, a face and a parallel edge, etc.  The full range  of  possible
departure  and approach angles is investigated and a solution chosen,
if possible, which allows manipulation in a single motion. Otherwise,
a  solution  is chosen which uses an intermediate position to regrasp
the object.  Thus, this facility  provides a method for grasping
general  polyhedra in arbitrary position and orientation, provided we
have a model of the object.

Arm planning is based on making complete motions, e.g. picking  up  an
object  and  putting  it  down.  If we pick up an object arbitrarily,
without thought for putting it down later, we may not be able to  put
it  down  as  desired  and  may  need  to  grasp  it again.  Complete
trajectories are pieced  together  from  various  segments, e.g. grasp,
departure,   mid-segment,   approach,  release.     Trajectories  are
specified by the user in an interpretive hand language (HAL) in terms
of  macros at the level of inserting a screw.  Endpoint positions and
orientations are often specified by positioning the arm itself in the
proper  position  and  recording joint angles, a form of "learning by
doing".  The language provides facilities for control using touch and
force sensing.

.CB Pump Assembly

Our first major task was assembly of an automobile  water  pump.    A
film which shows the process in detail is available for distribution
[Pingle and Paul, "Automated Pump Assembly"].
We describe the task in some detail to show the level of  programming.

The pump parts include pump base, cover,  gasket  and  screws.   We
chose a plausible industrial environment with tools in fixed places,
screws in a feeder, and pump body and cover on a  pallet.
It is located by vision, then  moved by the arm to a standard
position, up against some stops.  Pins are inserted into screw holes in
the pump body to guide alignment of gasket and  cover.  If  necessary
the  hand searches to seat the pins.

The gasket is placed over the
guide pins and visually inspected for correct placement.   The  cover
is  expected  to  be  within  about a quarter of an inch of its fixed
place on the pallet.   After locating the cover by  touch,  the  hand
places  the cover over the guide pins.   The hand then picks up a hex
head power screwdriver, picks up a screw from the feeder and  inserts
the  screw and, if  necessary, searches to seat the screw.    A
second screw is inserted.   The hand then removes the  two  pins  and
inserts  four  more screws, completing the assembly.  Finally, it tests
that the pump impeller turns freely.

Three forms of feedback are used, visual, tactile, and  force.    The
visual  feedback  is  provided  by  strictly special purpose programs
which have no general interest. We plan to generalize visual feedback
capabilities  and  include them in a system like that used to program
the rest of the task.

The manipulation parts of the assembly  were
programmed in the hand language, HAL.  The actual program follows:
.BEGIN CRBREAK RETAIN PREFACE 0; INDENT 2,18; SELECT 6
  BEGIN PUMP
  ALIGN		;align pump base at stops
  PIN P1 H1	;put pin P1 at hole H1
  PIN P2 H2	;put pin P2 at hole H2
  GASKET
  TOP
  SCREW1	;put in first 2 screws
  UNPIN H1 P1 H1A  ;remove pin P1 from hole H1
  UNPIN H2 P2 H2A  ;remove pin P2 from hole H2
  SCREW2	;insert last 4 screws
  TEST
  END
.END

Each of the commands is a macro.
The  task  was  performed  in  a general purpose hand language with a
control program which could be readily adapted to other manipulators.
Thus  the system is more than a special purpose demonstration.
.SSS Vision

During  the  past two years our vision effort has shifted from scenes
of blocks to outdoor scenes and scenes of  complex  objects.
In both cases, interpretation has made use of
world models.

A crucial part of our work with complex objects is our development of
suitable  representation of shape.  This is an area closely connected
with industrial applications of  research,  since  representation  of
shape  is important in programming of robots, design, display, visual
feedback, assembly, and symbolic description  for  recognition.

Wichman assembled the first robotics visual feedback  system [Wichman 1967].  
It was deficient in several ways:  only the outer
edges of the blocks were observed, the hand had  to  be  removed
from  view when visual checking was done, and the technique was limited
in its domain of objects.

Gill then improved  these  aspects  by  recognizing  hand  marks  and
internal  edges  of  blocks [Gill 1972].
The system was model driven in that
specifying the projected appearance of a corner  in  a  small  window
programmed  the system for a new task.  But the system was limited to
tasks with polyhedra, e.g. stacking blocks and  inserting  blocks  into
holes.

A class of representations of shape has been  applied to
symbolic description of shapes  of  toys  and  tools  [Agin 1972, Nevatia 1973].
The representation  depends  on  a  part/whole  description of objects in
terms of parts which may themselves be composed  of  parts.       The
success  of  any  part/whole representation depends on the utility of
the primitive parts; within the representation,  dominant  primitives
are  "generalized  cones",  originating  from  a formalization called
"generalized translational invariance".     These  primitives  are
locally  defined  by  an  arbitrary  cross  section and a space curve
called the axis, along which the cross sections are translated normal
to the axis.

We  have  developed  laser  depth  ranging  hardware  which  has been
operative since January 1971.  The device is very simple and  can  be
replicated  now  for  less  than  $1000,  assuming  that  a  suitably
sensitive camera tube such as a silicon vidicon or solid state sensor
is available.  From that experimental data, we have obtained complete
descriptions of a doll, a toy  horse,  a  glove,  etc., in  terms  of
part/whole descriptions in the representation just described.     The
same techniques could be used for monocular images, with considerable
benefit,  in  spite  of  the added difficulty of using only monocular
information.      We are now writing programs which match these graph
descriptions for recognition.

The work on visual feedback depends on display techniques which  have
been  developed here and elsewhere.  An interactive program GEOMED [Baumgart 1972a]
was developed to allow description of objects by  building  them
up  from  a set of geometric primitives.  The usually tedious task of
input of descriptions of complex objects is much simplified.  For our
purposes,  a symbolic line drawing output is necessary; a fast hidden
line elimination program with symbolic line output structure has been
written.

Working with outdoor scenes introduces new difficulties: surfaces are
textured, line finders etc.,  have  been  specialized  to  scenes  of
polyhedra.     We have made substantial progress by incorporating new
visual modules such as color region finders with a world model.   The
first  of these efforts [Bajcsy 1972] included a color region finder and Fourier
descriptors of texture.  Textures were described  by  directionality,
contrast,  element  size and spacing.  These interpretations from the
Fourier transform are useful but not always valid, and  a  discussion
of  the limitations of Fourier descriptors was included.   Depth cues
were obtained from the gradient of texture.  The results of color and
texture  region  growing  were  shown,  and  a  simulation  made of
combining these various modes with a world model.     An  interesting
conclusion  was  that three dimensional interpretations and cues were
the most semantic help in scene interpretation.

A  second  project has dealt with outdoor scenes
[Yakimovsky 1973].  Yakimovsky made a region-based system  which  sequentially
merges   regions   based  on  semantics  of  familiar  scenes,  using
two-dimensional image properties.    The system has an  initial  stage
which  is  very  much  like  other region approaches, merging regions
based on similarity of color and other crude descriptors, except  that
it eliminates weakest boundaries first. The second stage introduces a
world model and a means of estimating the best interpretation of  the
scene  in  terms  of  that model.
The semantic evaluation provides much better regions
than the same system without the semantics.
It has been demonstrated on road scenes, for
which rather good segmentations and labellings have been  achieved.  An
application was also made to heart angiograms.

In  human and animal peception, stereo and motion perception of depth
are important.     Several of these mechanisms have been  programmed.
Nevatia [1973] evaluated motion parallax of a moving observer for scenes of
rocks.     That program tracked by correlation subsequent images in a
series  of  images with small angle between images.     The technique
allows large baselines for triangulation.
Another approach to stereo has been carried out on outdoor scenes [Hannah
unpublished].

An edge operator
[Hueckel 1971] gives a good indication, based  on  local  brightness, of
whether or not there is an edge near the center of a neighborhood. If
there is an edge, its  position  and  location  are  relatively  well
determined.

Differencing techniques have been used to find changes
in scenes [Quam 1972].  Color region  growing  techniques  have  been  used.
Accomodation  of camera parameters to optimize image quality for each
task has been extensively used.


A  focussing
module  allows automatic focussing.
Color identification modules have been
written; the latest incorporates the Retinex model of Land to achieve
a   certain   color   constancy,  independent  of  the  variation  of
illuminance spectrum from scene  to  scene  (sunlight,  incandescent,
xenon  arc,  flourescent) or within a scene (reflections from colored
objects).
Calibration modules allow
maintaining  a  system  in  a  well-calibrated  state   to   maintain
reliability, and increase reliability by self-calibration.

Programs  have  been  written  to understand scenes of blocks
given line drawings.  An early version  recognized only outlines of
isolated  objects.  A later program, [Falk 1972], arrived at segmentations
into objects by techniques which were extensions of Guzman's, but using
lines  rather  than  regions.   This dealt more effectively
with missing and extraneous edges.   The  system  used  very  limited
prototypes of objects, using size in an important and restrictive way
to identify objects and their spatial relations.  Missing edges  were
hypothesized for a line verifier program to confirm or reject.

Still another model-based program [Grape 1973] used models of a
parallelipiped and a  wedge
to perform the segmentation into objects corresponding to models.  It
is able to handle a variety of missing  and  extraneous  edges.

The thrust of all these efforts is the use of models for perception.

.begin bib

[Agin 1972] G. Agin, "Description and Representation of  Curved  Objects",
PhD Thesis in Computer Science, Stanford A. I. Memo AIM-173, October 1972.

[Bajcsy 1972] R. Bajcsy, "Computer Identification of Visual Texture", PhD Thesis in Computer
Science, Stanford A. I. Memo AIM-180, October 1972.

[Baumgart 1972a] B. Baumgart, "GEOMED - A Geometric Editor", May 1972.
Stanford A. I. Lab., SAILON-68, 1972.

[Baumgart 1972b] Baumgart, Bruce G., "Winged Edge Polyhedron Representation", 
Stanford A. I. Memo AIM-179, October 1972.

[Binford 1973a] T. Binford, "Sensor Systems for  Manipulation", E. Heer (Ed), %2Remotely
Manned Systems,%1 Calif. Inst. Tech., Pasadena, 1973.

[Binford 1973b] T. O. Binford and Jay M. Tenenbaum, "Computer Vision",
%3Computer%1 (IEEE), May 1973.

[Earnest 1967] L. D. Earnest, "Choosing an Eye for a Computer", Stanford A. I.
Memo AIM-51, April 1967.

[Falk 1971] G. Falk, "Scene Analysis Based on Imperfect Edge Data", %2Proc. IJCAI,%1
Brit. Comp. Soc., London, Sept. 1971.

[Falk 1972] G. Falk, "Interpretation of Imperfect Line Data as a
Three-Dimensional Scene", %2J. Artificial Intelligence,%1 Vol 3,
No. 2, 1972.

[Feldman 1969] J. Feldman, et al,
"The Stanford Hand-Eye Project", %2Proc. IJCAI,%1
Washington D.C., 1969.

[Feldman 1970] J.A.Feldman, "Getting a Computer to see Simple Scenes", %2IEEE
Student Journal,%1 Sept. 1970.

[Feldman 1971a] J. Feldman and R. Sproull, "System Support for the Stanford
Hand-Eye System", %3Proc. IJCAI,%1 British Computer Soc., London, Sept. 1971.

[Feldman 1971b] J. Feldman, et al, "The Use of Vision and Manipulation to Solve
the "Instant Insanity" Puzzle", %2Proc. IJCAI,%1 Brit. Comp. Soc., London, Sept. 1971.

[Feldman 1972] J. Feldman, et al, "Recent Developments in SAIL -- An Algol-Based 
Language for Artificial Intelligence", %2Proc. FJCC,%1 1972.

[Gill 1972] Aharon Gill, "Visual Feedback and Related Problems in Computer-controlled
Hand-eye Coordination", PhD Thesis in EE, Stanford A. I. Memo AIM-178,
October 1972.

[Grape 1973]  Gunnar R. Grape "Model-Based (Intermediate-Level)
Computer Vision", PhD thesis in Comp. Sci., Stanford A. I. Memo AIM-201,
May 1973.

[Hueckel 1971] M.H. Hueckel, "An Operator Which Locates Edges in Digitized
Pictures", Stanford A. I. Memo AIM-105, December 1969, and
%2J. ACM,%1 Vol. 18, No. 1, January 1971.

[Kahn 1971] M. Kahn and B. Roth, "The Near-Minimum-time Control of Open-Loop
Articulated Kinematic Chains", %2Trans. ASME,%1 Sept 1971.

[Kelly 1970] Michael D. Kelly, "Visual Identification of People by 
Computer", PhD thesis in Comp. Sci., Stanford A. I. Memo AIM-130, July 1970.

[McCarthy 1970] J. McCarthy, "Computer Control of a Hand and Eye",
%2Proc. 3rd All-Union Conference on Automatic Control (Technical
Cybernetics),%1 Nauka, Moscow, 1967 (Russian).

[Montanari 1969] U. Montanari, "Continuous Skeletons from Digitized Images",
%2J. ACM,%1 October 1969.

[Montanari 1970a] U. Montanari, "A Note on Minimal Length Polygonal Approximation
to a Digitized Contour", %2Comm. ACM,%1 January 1970.

[Montanari 1970b] U. Montanari, "On Limit Properties in 
Digitization Schemes", %2J. ACM,%1 April 1970.

[Montanari 1970c] U.Montanari, "Separable Graphs, Planar Graphs
and Web Grammars", %2Information and Control,%1 May 1970.

[Montanari 1970d] U. Montanari, "Heuristically Guided Search and Chromosome
Matching", %2Artificial Intelligence,%1 Vol 1, No. 4, December 1970.

[Montanari 1971] U. Montanari, "On the Optimal Detection of Curves in Noisy
Pictures", %2Comm. ACM,%1 May 1971.

[Nevatia 1973] R.K.Nevatia and T.O.Binford, "Structured Descriptions of
Complex Objects", %2Proc. IJCAI,%1 Stanford University, August 1973.

[Paul 1969] R.Paul, G.Falk, J.Feldman, "The Computer Representation of
Simply Described Scenes", %2Proc 2nd Illinois Graphics Conf.,%1 Univ. Illinois, April 1969.

[Paul 1971] R. Paul,  "Trajectory  Control  of  a  Computer  Arm", %2Proc. IJCAI,%1
Brit. Comp. Sci., London, Sept. 1971.

[Paul 1972] R. Paul, "Modelling, Trajectory Calculation and Servoing of  a
Computer  Controlled  Arm",  PhD thesis in Comp. Sci.,
Stanford A. I. Memo AIM-177, Sept. 1972.

[Pieper 1968] Donald L. Pieper, "The Kinematics of Manipulators
under computer Control", Stanford A. I. Memo AIM-72, October 1968.

[Pingle 1968] K. Pingle, J. Singer, and W.Wichman, "Computer Control
of a Mechanical Arm through Visual Input", %2Proc. IFIP
Congress 1968.%1

[Pingle 1970] K. Pingle, "Visual Perception by a Computer", in 
%2Automatic Interpretation and Classification of Images,%1 Academic
Press, New York, 1970.

[Pingle  1972] K. K. Pingle and J. M. Tenenbaum, "An Accomodating Edge
Follower", %2Proc. IJCAI,%1 Brit. Comp. Soc., London, 1971.

[Quam 1972] L. H. Quam, et al,
"Computer  Interactive  Picture Processing", Stanford A. I.
Memo AIM-166, April 1972.

[Scheinman 1969] V. D. Scheinman, "Design  of  a  Computer  Manipulator",
Stanford A. I. Memo AIM-92, June 1969.

[Schmidt 1971] R. A. Schmidt, "A study of the Real-Time
Control of a Computer-Driven Vehicle", PhD. thesis in EE, Stanford
A. I. Memo AIM-149, August 1971.

[Sobel 1970] Irwin Sobel, "Camera Models and Machine Perception", Stanford
A. I. Memo AIM-121, May, 1970.

[Tenenbaum 1970] J. M. Tenenbaum, "Accommodation in Computer Vision", Stanford
A. I. Memo AIM-134, September 1970.

[Tenenbaum 1971] J. M. Tenenbaum, et al, "A Laboratory for Hand-Eye
Research", %2Proc IFIP Congress 1971.%1

[Wichman 1967] W. Wichman, "Use of optical Feedback in the Computer Control 
of an Arm", Stanford A. I. Memo
AIM-56, August 1967.

[Yakimovsky 1972] Y. Yakimovsky and J. A. Feldman, 
"A Semantics-Based Decision Theoretic Region Analyzer" 
%2Proc. IJCAI,%1 Stanford U., August 1973.

.cb FILMS

Gary Feldman, "Butterfinger", 16mm color with sound, 8 min.,
March 1968.

Gary Feldman and Donald Pieper, "Avoid", 16mm
silent, color, 5 minutes, March 1969.

Richard Paul and Karl Pingle, "Instant Insanity", 16mm color, silent
6 min., August 1971.

Suzanne Kandra, "Motion and Vision", 16mm color, sound,
22 min., November 1972.

Richard Paul and Karl Pingle "Automated Pump Assembly", 16mm color,
Silent, 7min, April 1973.

.end
.ss Theoretical Studies

Members of our project have pioneered in mathematical
theory of computation, representation theory, and grammatical inference.
This work is not a proper subcategory of artificial intelligence in that
it deals with problems that are basic to all of computer science.

In addition to ARPA sponsorship of this work, the mathematical theory of
computation activities received some support from the National Aeronautics
and Space Administration and the grammatical inference group has received
a grant from the National Science Foundation.

.SSS Mathematical Theory of Computation
.MTC:SUB2!
.begin

The idea that computer scientists should study computations 
themselves rather then just the notion of computability (i.e. recursion 
theory) was suggested in 1963 by McCarthy [1, 2].  These early papers
suggested that mathematical methods could be used to prove (or disprove)
the following properties of programs:
.begin subpar
1.  a program is correct,
2.  a program terminates,
3.  two programs are equivalent,
4.  a translation procedure between two languages is correct, (i.e. it preserves the meaning  of a program),
5.  optimized programs are equivalent to the original,
6.  one program uses less resources than another and is therefore more efficient.
.END

These are simply technical descriptions of a programer's day to day
problems.  The notion of correctness of a program is just -- "How do we know
that a particular program solves the problem that it was intended to?"  The
usual way of putting it is: "Does my program have bugs in it".  A correct 
mathematical description of what this means is a central problem in MTC and 
is a genuine first step in any attempt to mechanize the debugging of programs.
The equivalence of programs is similar in that until there are clear ways of
describing what a program does, saying that they "do" the same thing is 
impossible.  These technical problems are now well enough understood so 
that serious attempts to apply the results to "real" programs are beginning.

Attempts to formalize these questions have proceeded along several
lines simultaneously.  In [4, 6] McCarthy and Mansfield discussed new languages
for expressing these notions were considered.  [4] considered a first order 
logic which contained an "undefined" truth-value.  This was one way of
explaining what was meant by computations which didn't terminate.  [5] used a 
traditional first order logic to describe a subset of ALGOL. 

In [3] McCarthy proposed that computers themselves might be used to
check the correctness of proofs in formal systems, and was the first to 
actually construct a program to carry this out.  This suggests that one could
check or possibly look for solutions to the above problems (in the form of 
proofs in some formal system).  As a result a series of proof checkers has
been built.  The first is reported in [7].

In 1966 Floyd [8] published his now well known method of assigning 
assertions to the paths in a flowchart, in order to find verification 
conditions the truth of which guarantee the "correctness" of the original
program.  

McCarthy, Painter and Kaplan [9, 10, 11, 12, 13, 14] used the ideas in
[4, 8] to prove:
.begin subpar
1) the correctness of a compiler for arithmetic expressions,
2) the correctness of several compilers for algol-like programs, 
3) the equivalence of some algorithms.  
.END
Kaplan also gave some completeness results for a formal system which talks 
about assignment statements [10], and discussed the equivalence of programs 
[13, 14]. During this time another proof checker was written by W. Weiher [15].  

In a series of articles Z. Manna extended and expanded Floyd's original
ideas.  With  A. Pneulli [16, 17] he discussed the relationship between the 
termination, correctness and equivalence of recursively defined functions and
the satisfiability (or unsatisfiability) of certain first order formulas.  In 
[17] they work out an example using the 91 function.  In [18] Manna extended 
his ideas to non-deterministic programs.  E. Ashcroft and he did a similar 
thing for parallel programs in [21].  

P. Hayes [18] again attacked the problem of a three-valued predicate 
logic, this time with a machine implementation in mind.  This coincided with
a paper of Manna and McCarthy [19], which used this logic.

About this time (1969) several important developments occurred
which allowed the above questions to be reexamined from different points
of view.  
.BEGIN PREFACE 0; INDENT 0,3; AT 8 ⊂BREAK⊃; nojust
	1. In [22] Z. Manna showed how to formulate the notion of partial
correctness in second logic.  
	2. C. A. R. Hoare [24] published a paper describing a new formalism
for expressing the meanings of programs in terms of input/output relations.
	3. S. Igarashi [23] gave an axiomatic description of an ALGOL-like
language.
	4. D. Scott suggested using the typed lambda calculus for studying
MTC and first described IN 1970 a mathematical model of Church's lambda 
calculus.
.END

These together with McCarthy's axiomatic approach now represent 
the most important directions in MTC research.  They express different 
points of view towards the meanings (or semantics) of programs.  

Manna (following Floyd) describes the effects of a program by showing 
what kinds of relations must hold among the values of the program variables 
at different points in the execution of the program. In particular between 
the input and the output.  In [31] Floyd suggests an interactive system
for designing correct programs.  These ideas are systematized and expanded
by Manna in [34].  He and Ashcroft show how to remove GOTO statements from
programs and replace them by WHILE statements in [33].

Hoare shows how properties (including the meaning) of a program 
can be expressed as rules of inference in his formal system and how these
rules can be used to generate the relations described by Floyd and Manna. 
This puts their approach in a formal setting suitable for treatment on a
computer. Work on this formal system is at present being aggressively pursued.
Igarashi, London, and Luckham [39] have increased the scope of the original rules
and have programed a system called VCG (for verification condition generator)
which takes PASCAL programs together with assertions assigned to loops in the
program and uses the Hoare rules to automatically generate verification
conditions the proof of which guarantee the correctness of the original
program.  These sentences are then given to a resolution theorem prover [26]
which tries to prove them.

There is also a project started by Suzuki under
the direction of Luckham to develop programs to take account of particular
properties of arithmetic and arrays when trying to prove the verification
conditions.  London also produced an informal proof of two Lisp compilers [35].

Igarashi's formal system [23] differs from Hoare's in that the rules
of inference act directly on the programs themselves rather than properties
of such programs.  

Scott's work assumes that the most suitable meaning for a program 
is the function which it computes and essentially ignores how that computation 
proceeds.  The other approaches are more intentional in that: 
.BEGIN SUBPAR
1) they may not necessarily mention that function explicitly although it might appear implicitly. 
2) they can (and do) consider notions of meaning that are stronger than Scott's.  
.END
For example programs might have to have "similar" computation sequences 
before considering them equivalent [25].

A computer program LCF (for "logic for computable functions") has
been implemented by Milner [26]. This logic uses the typed lambda calculus
to defines the semantics of programs.  Exactly how to do this was worked
out by Weyhrauch and Milner [28, 29, 30].  In conjunction Newey worked on the
axiomatization of arithmetic, finite sets, and lists in the LCF 
environment.  This work is still continuing.  In addition Milner and
Weyhrauch worked with Scott on an axiomatization of the type free lambda
calculus.  Much of this work was informally summarized in [32].

McCarthy attempts to give an axiomatic treatment to a programming 
language by describing its abstract syntax in first order logic and stating 
properties of the programming language directly as axioms.  This approach 
has prompted Weyhrauch to begin the design of a new first order logic
proof checker based on natural deduction.  This proof checker is expected
to incorporate the more interesting features of LCF and will draw heavily
on the knowledge gained from using LCF to attempt to make the new first
order proof checker a viable tool for use in proving  properties of
programs.

This work is all being brought together by projects that are
still to a large extent unfinished.  They include 
.BEGIN PREFACE 0; INDENT 0,3; AT 8 ⊂BREAK⊃; nojust
	1.  a new version of LCF including a facility to search for
proofs automatically;
	2.  the description of the language PASCAL in terms of both 
LCF and in first order logic (in the style of McCarthy)
in order to have a realistic comparison between these
approaches and that of Floyd, Hoare, et al;
	3.  a continuation of Newey's work;
	4.  the discussion of LISP semantics in LCF and an attempt
to prove the correctness of the London compilers in a 
formal way (this is also being done by Newey);
	5.  the design of both special purpose and domain independent
proving procedures specifically with program correctness 
in mind;
	6.  the design of languages for describing such proof procedures;
	7.  the embedding of these ideas in the new first order checker.
.END

In addition to the work described above, Ashcroft, Manna, and
Pneuli [36], and Chandra and Manna [37] have published results related to
program schemas.  Manna's forthcoming book [37] will be the first general
reference in this field.

Some of these references appeared first as A. I. memos and were
later published in journals.  In such cases both references appear in
the bibliography.
.END
.begin bib; aimer;

[1]	McCarthy, John, "A Basis for a Mathematical Theory of Computation", in
   Biaffort, P., and Herschberg, D., (eds.), %2Computer Programming and Formal
             Systems%1, North-Holland, Amsterdam, 1963.

[2]	McCarthy, John, "Towards a Mathematical Theory of Computation",
	     %2Proc. IFIP Congress 62%1, North-Holland, Amsterdam, 1963.

[3]	McCarthy, John, "Checking Mathematical Proofs by Computer," in
	     %2Proc. Symp. on Recursive Function Theory (1961)%1, American 
	     Mathematical Society, 1962.

[4]	McCarthy, John, "Predicate Calculus with `UNDEFINED' as a Truth-value",
	     AIM-1, March 1963.

[5]	McCarthy, John, "A Formal Description of a Subset of Algol", AIM-24,
September 1964; also in Steele, T., (ed.), %2Formal Language Description Languages,%1
North Holland, Amsterdam, 1966.

[6]	Mansfield, R., "A Formal System of Computation", AIM-25,
September 1964.

[7]	McCarthy, John, "A Proof-checker for Predicate Calculus", AIM-27, March 1965.

[8]	Floyd, R. W., "Assigning Meanings to programs,"
Vol. 19, American Mathematical Society, 19-32, 1967.

[9]	McCarthy, John, and Painter, J., "Correctness of a Compiler for Arithmetic
	     Expressions", AIM-40, April 1966; also
in %2Mathematical Aspects of Computer Science,%1
Proc. Symposia in Applied Mathematics, Amer. Math. Soc., New York, 1967.

[10]	Painter, J., "Semantic Correctness of a Compiler for an Algol-like Language",
 AIM-44, March 1967.

[11]	Kaplan, D., "Some Completeness Results in the Mathematical Theory of 
Computation", AIM-45, October 1966; also
in %2J. ACM,%1 January 1968.

[12]	Kaplan, D., "Correctness of a Compiler for Algol-like programs", AIM-48,
July 1967.

[13]	Kaplan, D., "A Formal Theory Concerning the Equivalence of Algorithms",
AIM-59, May 1968.

[14]	Kaplan, D., "The Formal Theoretic Analysis of Strong Equivalence for 
Elemental Programs", AIM-60, June 1968.

[15]	Weiher, William, "The PDP-6 Proof Checker", AIM-53, June 1967.

[16]	Manna, Zohar, and Pnueli, Amir, "The Validity Problem of the 91-function",
AIM-68, August 1968.

[17]	Manna, Zohar, and Pneuli, Amir, "Formalization of Properties of Recursively
Defined Functions", AIM-82, March 1969; also in %2J. ACM,%1 Vol. 17, No. 3,
July 1970.

[18]	Hayes, Patrick J., "A Machine-oriented Formulation of the Extended Functional
 Calculus", AIM-86, June, 1969.

[19]	Manna, Zohar, and McCarthy, John, "Properties of Programs and Partial 
 Function Logic", AIM-100, October 1969; also
in Meltzer, B. and Michie, D. (eds.), %2Machine Intelligence 5,%1
Edinburgh University Press, Edinburgh, 1970.

[20]	Manna, Zohar, "The Correctness of Non-deterministic Programs", AIM-95,
August 1969; also
in %2Artificial Intelligence,%1 Vol. 1, No. 1, 1970.

[21]	Ashcroft, Edward, and Manna, Zohar, "Formalization of Properties of Parallel
Programs", AIM-110, February 1970; also
in %2Machine Intelligence 6,%1  Edinburgh University
Press, Edinburgh, 1971.

[22]	Manna, Zohar, "Second-order Mathematical Theory of Computation", AIM-111,
March 1970; also
in %2Proc. ACM Symposium on Theory of Computing,%1  May 1970.

[23]	Igarashi, Shigeru, "Semantics of Algol-like Statements", AIM-129, June 1970.

[24]    Hoare, C.A.R., "An Axiomatic Basis for Computer Programming",
%2Comm. ACM 12,%1 No. 10, pp.576-580, 1969.

[25]	Milner, Robin, "An Algebraic Definition of Simulation between Programs",
AIM-142, February, 1971; also
in %2Proc. IJCAI,%1 British Computer Society, London, 1971.

[26]    Allen, John and Luckham, David, "An Interactive Theorem-proving Program",
AIM-103, October 1971.

[27]    Milner, Robin, "Logic for Computable Functions; Description of a Machine
Implementation", AIM-169, May 1972.

[28]    Milner, Robin, "Implementation and Applications of Scott's Logic for
Computable Functions", %2Proc. ACM Conf. on Proving Assertions about
Programs,%1  ACM Sigplan Notices, January 1972.

[29]    Milner, Robin and Weyhrauch, Richard, "Proving Compiler Correctness  
in a Mechanised Logic", %2Machine Intelligence 7,%1 Edinburgh University
Press, Edinburgh, 1972.

[30]    Weyhrauch, Richard and Milner, Robin, "Program Semantics and Correctness
in a Mechanized Logic", %2Proc. USA-Japan Computer Conference,%1 Tokyo, 1972.

[31]	Floyd, Robert W., "Toward Interactive Design of Correct Programs", AIM-150,
September 1971; also in %2Proc. IFIP Congress 1971%1.

[32]	Manna, Zohar, Ness, Stephen, and Vuillemin, Jean, "Inductive Methods for
Proving Properties of Programs", AIM-154, November 1971; also
in %2ACM Sigplan Notices, Vol. 7, No. 1,%1 January 1972.

[33]	Ashcroft, Edward, and Manna, Zohar, "The Translation of `GO-TO' Programs
to `WHILE' Programs", AIM-138, January 1971; also
in %2Proc. IFIP Congress 1971%1.

[34]	Manna, Zohar, "Mathematical Theory of Partial Correctness", AIM-139,
January 1971; also
in %2J. Comp. and Sys. Sci.,%1 June 1971.

[35]	London, Ralph L., "Correctness of Two Compilers for a LISP Subset", AIM-151,
October 1971.

[36]	Ashcroft, Edward, Manna, Zohar, and Pneuli, Amir, "Decidable Properties of
Monadic Functional Schemas", AIM-148, July 1971.

[37]	Chandra, Ashok, and Manna, Zohar, "Program Schemas with Equality", AIM-158,
December 1971.

[38]	Manna, Zohar, %2Introduction to Mathematical Theory of Computation%1,
McGraw-Hill, New York, 1974 (to appear).

[39]	Igarashi, Shigeru, London, Ralph, Luckham, David, "Automatic Program
Verification I:  A Logical Basis and its Implementation", AIM-200, May 1973.

.END
.sss Representation Theory

.turn on "%";
When we try to make a computer program that solves a certain class of
problem, our first task is to decide what information is involved in
stating the problem and is available to help in its solution.  Next we
must decide how this information is to be represented in the memory of
the computer.  Only then can we choose the algorithms for manipulating
this information to solve our problem.  %2Representation theory%1 deals
with what information we need and how it is represented in the computer.  
%2Heuristics%1 is concerned with the structure of the problem solving
algorithms.
.turn off "%"

In the past, much work in artificial intelligence has been content with a
rather perfunctory approach to representations.  A representation is
chosen rather quickly for a class of problems and then all attention
is turned to devising, programming, and testing heuristics.  The trouble
with this approach is that the resulting programs lack generality and
are not readily modifiable to attack new classes of problems.

The first goal of representation theory is to devise a general way of
representing information in the computer.  It should be capable of
representing any state of partial information necessary to solve it.  In
1958, McCarthy posed the problem of making a program with "common sense"
in approximately these terms and suggested using sentences in an
appropriate formal language to represent what the program knows [1].
The advantage of representing information by sentences is that sentences
have other sentences as logical consequences and the program can find
consequences relevant to the goals at hand.  Thus, representation of
information by sentences allows the following.
.begin indent 0,3; nojust
1.  A person can instruct the system without detailed knowledge of what
sentences are already in memory.  That is, the procedures for solving
a problem using information in sentence form do not require that the
information be in a particular order, nor even a particular grouping
of information into sentences.  All they require is that what to do
is a logical consequence of the collection of sentences.

2.  Similar considerations apply to information generated by the program
itself.

3.  Representing information by sentences seems to be the only clean
way of separating that information which is common knowledge (and so
should be already in the system) from information about a particular
problem.
.end

On the other hand, because each sentence has to carry with it much of
its frame of reference, representation of information by sentences is
very voluminous.  It seems clear that other forms of information
(e.g. tables) must also be used, but the content of these other forms
should be described by sentences.

In the last ten years, considerable progress has been made in the use
of the sentence representation.  In the heuristic direction, theorem
proving and problem solving programs based on J. Allen Robinson's
resolution have been developed by both Green and Luckham, among others
[see {YON(TP)}].  The theory of how to represent facts
concerning causality, ability, and knowledge for artificial intelligence
has been developed mainly by McCarthy and his students.

The early work in this project revolved around McCarthy's "advice taker"
ideas [2-7].  McCarthy and Hayes [8] restructured the problem and connected
this work to the subject of philosophical logic.

Later related work includes Becker's semantic memory system [9, 10],
Sandewall's representation of natural language information in predicate
calculus [11], and Hayes' study of the frame problem [12].

.begin bib; aimer;

[1] John McCarthy, "Programs with Common Sense" in %2Proc. 1958 Teddington Conf. on
Mechanisation of Thought Processes%1,
Vol. 1, pp 77-84, H. M. Stationary Office, London, 1960;
reprinted in M. Minsky (ed.), %2Semantic
Information Processing%1, MIT Press, Cambridge, Mass., 1968.

[2]  John McCarthy, "Situations, Actions, and Causal Laws", AIM-2, July 1963.

[3]  F. Safier, "`The Mikado' as an Advice Taker Problem", AIM-3, July 1963.

[4]  John McCarthy, "Programs with Common Sense", AIM-7, September 1963.

[5]  M. Finkelstein and F. Safier, "Axiomatization and Implementation", AIM-15,
June 1964.

[6]  John McCarthy, "Formal Description of the Game of Pang-ke", AIM-17, July 1964.

[7]  Barbara Huberman, "Advice Taker and GPS", AIM-33, June 1965.

[8]  John McCarthy and Patrick Hayes, "Some Philosophical Problems from the
Standpoint of Artificial Intelligence", AIM-73, November 1968; also in
D. Michie (ed.), %2Machine Intelligence 4%1, American Elsevier, New York, 1969.

[9]  Joseph Becker, "The Modeling of Simple Analogic and Inductive Processes
in a Semantic Memory System", AIM-77, January 1969; also in %2Proc. IJCAI%1,
Washington D. C., 1969.

[10] Joseph Becker, "An Information-processing Model of Intermediate-level
Cognition", AIM-119, May 1970.

[11] Erik Sandewall, "Representing Natural-language Information in Predicate
Calculus", AIM-128, July 1970.

[12] Patrick Hayes, "The Frame Problem and Related Problems in Artificial
Intelligence", AIM-153, November 1971.

.end
.sss Grammatical Inference

Professor Feldman and a small group
have been investigating the problem of grammatical inference.
That is, given a set of strings which has been chosen in a random way
from a formal language such as a context-free language, to make a
"reasonable" inference of the grammar for the language.

Feldman has studied a very general class of complexity measures and shown
that the least complex choice of grammar from an enumerable class of
grammars (which are general rewriting systems), can be found, and he
gives an algorithm for discovering it [3].
This approach is also being applied to the inference of good programs
for producing specified input-output behavior.

.begin bib; aimer;

[1] Jerome A. Feldman, "First Thoughts on Grammatical Inference", AIM-55,
August 1967.

[2] Jerome A. Feldman, J. Gips, J. J. Horning, S. Reder, "Grammatical
Complexity and Inference", AIM-89, June 1969.

[3] Jerome A. Feldman, "Some Decidability Results on Grammatical Inference
and Complexity", AIM-93, August 1969; revised
May 1970; also in <Information and Control>, Vol. 20, No. 3, pp. 244-262,
April 1972.

[4] James Jay Horning, "A Study of Grammatical Inference", AIM-98, August 1969.

[5] Alan W. Biermann, J. A. Feldman, "On the Synthesis of Finite-state Acceptors",
AIM-114, April 1970.

[6] Alan W. Biermann, "On the Inference of Turing Machines from Sample
Computations", AIM-152, October 1971; also in <Artificial Intelligence J.>,
Vol. 3, No. 3, Fall 1972.

[7] Alan W. Biermann, "On the Synthesis of Finite-state Machines from Samples
of their Behavior", <IEEE Trans. Computers>, Vol. C-21, No. 6, June 1972.

[8] Jerome A. Feldman, A. W. Biermann, "A Survey of Grammatical Inference",
<Proc. Int. Congress on Pattern Recognition>, Honolulu, January 1971; also in
S. Watanabe (ed.), <Frontiers of Pattern Recognition>, Academic Press, 1972.

[9] Jerome A. Feldman, Paul Shields, "Total Complexity and Inference of
Best Programs", AIM-159, April 1972.

[10] Jerome A. Feldman, "Automatic Programming", AIM-160, February 1972.

.end
.SS Heuristic Programming

Heuristic programming techniques are a core discipline of artificial
intelligence.  Work on theorem proving, program generation, board
games, and symbolic computation make particularly heavy use of these
techniques.  An excellent general reference is the book by Nilsson [1].
Nilsson, of SRI, was supported in part by our project while writing it.

.sss Theorem Proving
.TP:sub2!;
The basis of the theorem-proving effort has  been the proof procedure
for  first-order logic with  equality, originally  developed by Allen
and Luckham [2].  This has  been extensively modified by J. Allen  in
recent months; the basic theorem-proving  program has been speeded up
by  a  factor  of  20,    an  input-output  language allowing  normal
mathematical notation  has been  added, and the  program will  select
search strategies automatically if  the user wishes (we refer to this
as automatic mode).  As  a result it is  possible for the program  to
be used by a person who is totally unfamiliar  with the theory of the
Resolution  principle  and  its  associated  rules  of inference  and
refinements.  A user's manual is now available [10].

This program  has been  used to  obtain proofs  of several  different
research  announcements in the  Notices of  the American Mathematical
Society, for example,  [7, 8,  and 9]. More recently (July  1972), J.
Morales learned to use the program  essentially by using it to obtain
proofs  of the results stated  in [9]  as an exercise.  In
the course  of doing this  he was  able to  formulate simple ways  of
using  the  prover to  generate  possible new  theorems  in the  same
spirit as [9],  and did in  fact succeed in extending the results  of
[9].  Furthermore,  he  was able to send the authors  proofs of their
results  before they  had actually  had time to  write them  up [R. H.
Cowen, private correspondence,   August 9, 1972].  Currently,  Morales
has been applying the theorem-prover  to problems in geometry [11, 12]
that have been the subject of  recent publications in the proceedings
of the  Polish National Academy  of Sciences.   He  has been able  to
give elementary  proofs of some  results to clarify  inaccuracies and
omissions. This  work  is  continuing  in   correspondence  with  the
authors.  The prover  is  also  being used  as  part of  the  program
verification system [see {YON(MTC)}].

A version  of the prover,
with user documentation  [10], has been  prepared for distribution  to
other research groups.  The addition  of a language in which the user
can  specify his  intuition about  how a  proof of a  given statement
might possibly  be obtained,  is in  progress.  J. Allen has  already
programmed a very preliminary  version of this "HUNCH" language,  and
has completed  the  systems debugging  necessary  to get  a  compiled
version  of Sussman's  CONNIVER  language running  here.  HUNCH
language  may be  implemented in  CONNIVER,  but discussions  on this
point are not  yet complete.  Initially,   it  is expected that  HUNCH
will  be   useful  in   continuing  with   more  difficult
applications  in  mathematics.

An alternative approach to theorem proving was developed in Cordell
Green's Thesis on QA3.  His work was done at SRI and his dissertation was
published here [5].

.begin bib; aimer;

[1] Nils Nilsson, %2Problem-solving Methods in Artificial Intelligence%1,
McGraw-Hill, New York, 1971.

[2]  John  Allen  and  David Luckham, "An  Interactive  Theorem-proving
Program", %2Machine Intelligence 5,%1
Edinburgh University Press, Edinburgh, 1970.

[3]  Richard  B.    Kieburtz  and  David   Luckham,    "Compatibility  and
Complexity  of Refinements  of the  Resolution  Principle", %2SIAM J.
Comput.%1, Vol. 1, No. 4, December 1972.

[4]  David Luckham  and  Nils J.   Nilsson,  "Extracting Information  from
Resolution  Proof Trees", %2Artificial Intelligence%1,  Vol. 2,   No.  1,
pp. 27-54, Spring 1971.

[5]  Cordell Green, "The Application of Theorem Proving to Question Answering
Systems", Ph.D. Thesis in E. E., AIM-96, August 1969.

[6]  J. Sussman and T. Winograd, "Micro Planner Manual", Project MAC Memo, MIT.

[7]  Chinthayamma, "Sets  of  Independent  Axioms  for  a  Ternary
Boolean Algebra", %2Notices Amer. Math. Soc.,%1 16, p. 654, 1969.

[8]  E. L. Marsden, "A  Note on Implicative  Models", %2Notices Amer. Math.
Soc.,%1 No. 682-02-7, p. 89, January 1971.

[9]  Robert   H.   Cowen,   Henry  Frisz,   Alan   Grenadir,   "Some   New
    Axiomatizations  in Group Theory", Preliminary  Report, %2Notices Amer.
    Math. Soc.,%1 No. 72T-112, p. 547, June 1972.

[10] J. R. Allen, "Preliminary  Users   Manual   for   an   Interative
Theorem-Prover",    Stanford   Artificial   Intelligence   Laboratory
Operating Note SAILON-73, 1973.

[11] L. Szcerba and W. Szmielew, "On the  Euclidean  Geometry Without  the
 Pasch Axiom", %2Bull. Acad. Polon. Sciences,%1 Ser. Sci. Math., Astronm,
Phys., 18, pp. 659-666, 1970.

[12] Szcerba,  L. W.,  "Independence of Pasch's Axiom", %2ibid.%1 [3], pp.
491-498.

.end
.sss Automatic Program Generation

This work is an  outgrowth of an attempt to  extend the applicability
of  the theorem-prover  to problems  in artificial  intelligence, and
makes use of a particular  notion of a problem environment (called  a
"semantic  frame")  which was  designed  for  that original  purpose.
However,    the system  as  it now  stands,   is  independent  of the
theorem-prover, and is best thought of as  a heuristic problem-solver
for a subset  of Hoare's logical system.  It  has been implemented in
LISP by J. Buchanan using the backtrack features of Micro-Planner.

It accepts  as  input an  environment of  programming  methods and  a
problem  and, if successful,   gives as output a  program for solving
the problem.   At the moment,   the output  programs are composed  of
the primitive operators of  the environment, assignments, conditional
branches,   while  loops,   and  non-recursive procedure  calls. This
system has been  used to generate  many programs for solving  various
problems  in robot  control,    everyday advice-taking  and
planning,   and  for computing  arithmetical  functions.   It  is  an
interactive  facility  and  incorporates  an  Advice  language  which
allows  the user  to state preferences  affecting the  output program
and heuristics for  speeding the  problem-solving process, and  also
to make  assumptions.

The system  is intended to  permit a  user to
oversee  the automatic  construction  of a  program according  to the
current  principles of  structured  programming.   There  is  also  a
library  facility and  the system  will incorporate  library routines
into the program under construction.
The  details of its
implementation will be  available in Jack Buchanan's Ph.D. Thesis
(in preparation).

.sss Board Games

.turn on "%"
Computer programs that play games such as chess or checkers are
deservedly important as research vehicles.
A Russian computer scientist has said [1] that chess plays the role
in Artificial Intelligence that the fruit fly plays in genetics.  
Just as the genetics of %2Drosophila%1 are studied not to breed better
flies but to study the laws of heredity, so we write chess programs,
not because it is important that computers play good chess, but because
chess provides a rather clear basis for comparing our ideas about
reasoning processes with human performance.  Weaknesses in the performance
of the program tell us about human mental processes that we failed to
identify.

.turn off "%"
John McCarthy supervised the development of a chess program at MIT.
He brought it here when he came and subsequently improved it a bit. 
In 1966, a match was held with a program
at what was then Carnegie Tech.  Neither program played especially well,
but Carnegie eventually resigned.  The Stanford program played several games in 1967
with a program at the Institute for Theoretical and Experimental Physics in
Moscow.  Again, both blundered frequently, but ours made some of
the worst moves.  By prior agreement, the games were not completed because
both programs were known to have essentially no end-game capability.

Barbara Huberman developed a program that handled certain important end game
situations and published her dissertation in 1968 [5].

Some early work on the game of Kalah produced a program that played rather
well [2, 3].

Arthur Samuel continued his long-standing development of a checkers program
when he arrived in 1966 [4].  His program is apparently still the best in
the world.  It does not defeat the best human players, but plays fairly well
against them.  Samuel subsequently decided to apply the
"signature table learning" scheme that he had developed for checkers to
speech recognition problems [see {YON(SPEECH)}].

Jonathan Ryder developed what was (and probably still is) the best Go program
to date [6].  It plays better than a beginning human, but it is still
quite weak by the standards of experienced players.  

Since 1971, we have done very little work on board games.

.begin bib; aimer;

[1]  A. Kronrod, "The Computer becomes More Intelligent", %2Isvestiya,%1
March 15, 1967; translated in %2Soviet Cybernetics:  Recent News Items,%1
No. 3, Rand Corp., Santa Monica, Calif., April 1967.

[2]  R. Russell, "Kalah -- the Game and the Program", AIM-22, September 1964.

[3]  R. Russell, "Improvements to the Kalah Program", AIM-23, September 1964.

[4]  Arthur Samuel, "Some Studies in Machine Learning using the Game of
Checkers, II -- Recent Progress", AIM-52, June 1967; also in %2IBM Journal%1,
November 1967.

[5]  Barbara J. Huberman, "A Program to Play Chess End Games",
Ph.D. Dissertation in Computer Science, AIM-65, August 1968.

[6]  Jonathan L. Ryder, "Heuristic Analysis of Large Trees as Generated in the
Game of Go", Ph.D. Dissertation in Computer Science, AIM-155, December 1971.

.end
.sss Symbolic Computation
.SYM:SUB2!

The use of computers to manipulate algebraic expressions and solve systems
of symbolic equations potentially offers substantial improvements in speed
and reduced error rate over pencil-and-paper methods.  As a consequence, it
becomes possible to tackle problems that are out of the range of practical
human capabilities.

Beginning in 1963, Enea and Wooldridge worked on the central problem of
algebraic simplification [1, 2].  By 1965, Korsvold had developed a working
system [3].

At about this time, Hearn became interested in the problem because of potential
application to problems in particle physics.  He developed a system called
REDUCE, which was written in LISP [4, 5].  Its initial
capabilities included:
.begin subpar;
a)  expansion and ordering of rational functions of polynomials,
b)  symbolic differentiation,
c)  substitutions in a wide variety of forms,
d)  reduction of quotients of polynomials by cancellation of common terms,
e)  calculation of symbolic determinates.
.end

REDUCE has been used for analysis of Feynman Diagrams and a number of other
problems in physics and engineering [6, 7, 12].  It has been extended in a
number of ways [8-11, 13, 14] and is still under development by Hearn at
the University of Utah.

George Collins spent a sabbatical year here (1972-3) developing his computational
system [15, 16].

.begin bib; aimer;

[1]	Enea, H. and Wooldridge, D. "Algebraic Simplication", AIM-5, August 1963.

[2]	Wooldridge, D., "An Algebraic Simplify Program in LISP", AIM-11,
	December 1963.

[3]	Korsvold, K., "An On Line Algebraic Simplification Program", AIM-37,
	November 1965.

[4]	Hearn, A., "Computation of Algebraic Properties of Elementary Particle 
	Reactions Using a Digital Computer", %2Comm. ACM%1 9, August 1966.

[5]	Hearn, A., "REDUCE Users' Manual", AIM-50, February 1967.

[6]	Brodsky, S. and Sullivan, J., "W-Boson Contribution to the Anomalous
	Magnetic Moment of the Muon", %2Physics Review%1, 156, 1644, 1967.

[7]	Campbell, J., "Algebraic Computation of Radiative Corrections for 
	Electron-Proton Scattering", %2Nuclear Physics%1 Vol. B1, 1967.

[8]	Hearn, A., "REDUCE, A User-Oriented Interactive System for Algebraic 
	Simplification", %2Proceedings for ACM Symposium on Interactive Systems for 
	Experimental Applied Mathematics%1, August 1967.

[9]	Hearn, A., "REDUCE, A User-Oriented Interactive System for Algebraic
	Simplification", AIM-57, October 1967.

[10]	Hearn, A., "The Problem of Substitution", %2Proceedings of IBM Summer Institute
	on Symbolic Mathematics by Computer%1, July 1968.

[11]	Hearn, A., "The Problem of Substitution", AIM-170, December 1968.

[12]	Hearn, A. and Campbell, J.A., "Symbolic Analysis of Feynman Diagrams by 
	Computer", AIM-91, August 1969; also in
	%2Journal of Computational Physics%1 5, 1970.

[13]	Hearn, A., "Applications of Symbol Manipulation in Theoretical Physics",
	%2Comm. ACM%1, August 1971.

[14]	Hearn, A., "REDUCE 2", AIM-133, October 1970.

[15]	Collins, George, "The Computing Time of the Euclidean Algorithm",
	AIM-187, January 1973.

[16]	Collins, George, and Horowitz, Ellis, "The Minimum Root Separation of
	a Polynomial", AIM-192, April 1973.

.end
.SS Natural Language

We have worked on two aspects of natural language understanding
that are still quite distinct, but may be expected to interconnect
eventually.

.SSS Speech Recognition
.speech:sub2!

Efforts  to  establish  a vocal  communication  link  with  a
digital  computer have  been underway at  Stanford since  1963. These
efforts have been  primarily concerned with  four areas of  research:
.begin subpar;
1)  basic  research   in  extracting  phonemic  and  linguistic information  from speech  waveforms,
2) the application of automatic  learning processes,
3) the use  of syntax  and semantics  to aid  speech recognition, and
4) speech  recognition systems have been used to control other processes.
.end
These  efforts have
been carried  out in  parallel with  varying  emphasis
at different times.

The fruits  of Stanford's speech research  program were first
seen in October  1964 when  Raj Reddy published  a report  describing
his preliminary  investigations on the  analysis of  speech waveforms
[1].  His system worked directly with a digital representation of the
speech waveform to do vowel recognition.

By  1966  Reddy  had built  a  much larger  system  which  obtained a
phonemic transcription and  which achieved segmentation of  connected
phrases utilizing hypotheses testing  [2].  This system represented a
significant contribution towards speech sound segmentation [3].  It
operated  on a subset  of the speech  of a  single cooperative
speaker.

	In 1967  Reddy and his  students had  refined several of  his
processes  and  published  papers  on  phoneme  grouping  for  speech
recognition [4],   pitch period determination  of speech sounds  [5],
and computer recognition of connected  speech [6].

1968 was  an extremely  productive year  for the Speech group.
Pierre  Vicens developed an efficient
preprocessing scheme for  speech analysis [7].  Reddy and his students
published papers on transcription of  phonemic symbols  [8],
phoneme-to-grapheme  translation of
English [9],
segmentation of  connected speech [10], and
 consonantal  clustering and connected speech  recognition
[11].   A general paper  by John
McCarthy,  Lester  Earnest,  Raj  Reddy,    and Pierre  Vicens
described the voice-controlled artificial arm developed at Stanford [12].

By   1969  the speech  recognition processes  were
successfully segmenting  and  parsing  continuous utterances  from  a
restricted  syntax [13, 14, 15].  A short film entitled "Hear Here" was made to
document recent accomplishments.

In mid 1970,
Prof. Reddy left Stanford to  join the faculty of Carnegie-Mellon
University  and Arthur Samuel  became the head  of the Stanford
speech  research  efforts.   Dr.  Samuel  had developed a
successful machine  learning scheme  which  had previously
been applied  to the  game of  checkers [16], [17].   He  resolved  to
apply them to speech recognition.

By 1971 the first speech  recognition  system
utilizing Samuel's learning  scheme was reported by George White [18].
This report  was  primarily concerned  with  the examination  of  the
properties of  signature trees and  the heuristics involved  in their
application  to  an  optimal  minimal  set  of  features  to  achieve
recognition.   Also at  this time,  M. M. Astrahan
described his
hyperphoneme method  [19], which  attempted  to  do  speech
recognition   by   mathematical  classifications   instead   of   the
traditional   phonemes   or   linguistic   categories.     This   was
accomplished  by  nearest-neighbor  classification  in  a  hyperspace
wherein cluster centers, or hyperphonemes, had been established.

In  1972  R. B. Thosar and  A. L. Samuel presented  a  report
concerning  some preliminary experiments  in speech recognition using
signature tables [20].   This approach  represented a general  attack
on speech recognition employing  learning mechanisms at each stage of
classification.

The speech effort in 1973 has been devoted to two areas.  First, a
mathematically rigorous examination and improvement of the signature
table learning mechanism has been accomplished by R. B. Thosar.  Second,
a segmentation scheme based on signature tables is being developed to
provide accurate segmentation together with probabilities or confidence
values for the most likely phoneme occuring during each segment.  This
process attempts to extract as much information as possible and to pass
this information to higher level processes.

In addition
to these activities, a new, high speed pitch detection scheme has been
developed by J. A. Moorer and has been submitted for publication [22].
.begin bib;

[1]  D. Raj Reddy, "Experiments on Automatic Speech Recognition  by  a
Digital Computer", Stanford A. I. Memo AIM-26, October 1964.

[2]  D. Raj  Reddy",  An  Approach to Computer Speech Recognition by
Direct Analysis of the Speech Waveform", Stanford A. I. Memo AIM-43,
September 1966.

[3]  D. Raj  Reddy, "Segmentation of Speech Sounds," %2J. Acoust. Soc.
Amer.%1, August 1966.

[4]  D. Raj Reddy,  "Phoneme  Grouping  for  Speech  Recognition,"  %2J.
Acoust. Soc. Amer.%1, May, 1967.

[5]  D. Raj  Reddy,  "Pitch  Period Determination of Speech Sounds,"
%2Comm. ACM%1, June, 1967.

[6]  D. Raj Reddy, "Computer  Recognition  of  Connected  Speech,"  %2J.
Acoust. Soc. Amer.%1, August, 1967.

[7]   Pierre  Vicens,  "Preprocessing  for  Speech  Analysis", Stanford
A.I. Memo AIM-71, October 1968.

[8]  D. Raj Reddy, "Computer Transcription of  Phonemic  Symbols",  %2J.
Acoust. Soc. Amer.%1, August 1968.

[9]   D. Raj Reddy, and Ann Robinson, "Phoneme-To-Grapheme Translation
of English", %2IEEE Trans. Audio and Electroacoustics%1, June 1968.

[10]  D. Raj Reddy, and P. Vicens,  "Procedures  for  Segmentation  of
Connected Speech," %2J. Audio Eng. Soc.%1, October 1968.

[11]  D. Raj  Reddy,  "Consonantal  Clustering  and Connected Speech
Recognition", %2Proc. Sixth International Congress of Acoustics%1, Vol. 2,
pp.  C-57 to C-60, Tokyo, 1968.

[12]   John McCarthy, Lester Earnest, D. Raj Reddy, and Pierre Vicens,
"A Computer With Hands, Eyes, and  Ears",  %2Proc. FJCC%1, 1968.

[13]   Pierre  Vicens, "Aspects of
Speech Recognition by Computer", Stanford A. I. Memo AIM-85, April 1969.

[14]  D. Raj  Reddy,  "On  the  Use  of Environmental, Syntactic and
Probabilistic Constraints in  Vision  and  Speech", Stanford A. I.
Memo AIM-78,  January 1969.

[15]  D. Raj Reddy and R. B. Neely, "Contextual Analysis of Phonemes
of English", Stanford A. I. Memo AIM-79, January 1969.

[16]  A. L. Samuel, "Some Studies in Machine Learning Using the Game
of Checkers," %2IBM Journal%1 3, 211-229, 1959.

[17]  A. L. Samuel, "Some Studies in Machine Learning Using  the  Game
of  Checkers,  II - Recent Progress," %2IBM Jour. of Res. and Dev.%1, 11,
pp.  601-617, November 1967.

[18]  George M. White,  "Machine Learning  Through  Signature  Trees.
Applications to Human Speech", Stanford A. I. Memo AIM-136,
October 1970.

[19] M. M. Astrahan, "Speech Analysis by Clustering, or the Hyper-
phoneme Method", Stanford A. I. Memo AIM-124, June 1970.

[20]  R. B. Thosar and A. L. Samuel, "Some Preliminary  Experiments in
Speech  Recognition  Using  Signature  Table  Learning",  ARPA Speech
Understanding Research Group Note 43, 1972.

[21]   R. B. Thosar,  "Estimation  of  Probability  Densities   using
Signature Tables for Application to Pattern Recognition", ARPA Speech
Understanding Research Group Note 81.

[22]  J. A. Moorer, "The Optimum-Comb Method of Pitch Period Analysis
in Speech", Stanford A. I. Memo AIM-207, July 1973.

.cb FILM

23. Raj Reddy, Dave Espar, Art Eisenson, "Hear Here", 16mm color with
sound, 1969.

.END
.sss Semantics

We have two sub-groups working within the  general  area  of  machine
translation   and   natural   language  understanding.  They  are  the
Preference Semantics  group  (Wilks  et  al.)    and  the  Conceptual
Dependency group (Schank et al.)

Both  groups  stress  the  centrality  of  meaning representation and
analysis, and the inferential manipulation of  such  representations,
for  the  task of natural language understanding.  Again, both assume
the importance of context, and of the expression of meaning in  terms
of  a  formal  system  of  meaning primitives, while at the same time
denying the centrality of syntactical analysis  in  the  conventional
linguist's  sense.     Both  have  capacity  for combining linguistic
knowledge with knowledge  of  the  real  world,  in  order  to  solve
problems  of  interpretation during the course of analysis.   The two
basic formalisms were set out definitively in [11 and  14],  and  the
theoretical basis for systems of this sort has been argued in [9, 11,
13].

The differences between the sub-groups are largely concerned with the
ordering  of  research  goals:   the  PS [Preference Semantics] group
emphasises  an  immediate  task  as   a   criterion   of   successful
understanding,  interlingual machine translation in the present case,
while the CD [Conceptual Dependency]  group  emphasises  independence
from  any  particular task.    A particular example of the difference
is provided by machine translation,  where,  from  a  given  semantic
representation  a PS program always constructs some particular output
string for that representation, whereas a CD program would  want  the
freedom  to  construct  one  of a number of possible representations.

Another,  more  philosophically  motivated  difference  of   approach
between  the  groups, concerns the time at which inferences are to be
made from semantic representations.   In the  PS  approach,  no  more
inferences  are  made than is necessary to solve the problem in hand,
and the representation is never made any "deeper" than necessary.  In
the  CD approach, a large number of inferences is made spontaneously.

Lastly,  the  two  approaches  both  aim   essentially   at   machine
translation  as  the fundamental test of a language understander, but
the CD approach emphasizes the treatment of human dialogue while  the
PS approach emphasizes the treatment of small texts as the definition
of a context.

We believe  that  these  approaches  are  complementary  rather  than
exclusive,  and that the parallel testing of different sub-hypotheses
in this way, within an overall  semantics-oriented  project,  can  be
stimulating and productive.

Both  sub-groups have had pilot systems running on the computer since
1970, but in the  last  year  both  have  implemented  much  stronger
running  programs.    During  the last year the PS implementation has
been enlarged from a basic mode to an extended mode  of  the  on-line
English-French  translator.   It accepts small paragraphs of English,
outputs the semantic representation it derives, and then  the  French
translation.   Since  it is semantics, rather than syntax, based, the
English input need not even be grammatically correct.

The basic  mode
of  Preference  Semantics  will  cope  with the problems presented by
sentences like "Give the bananas to the monkeys although they are not
ripe,  because they are very hungry"; that is to say, of attaching the
two "they"s correctly on the basis of what it knows about bananas and
monkeys  (which  have  different  genders in French, so the choice is
important).

The extended mode is called when referential problems in
a  paragraph require the manipulation of stronger partial information
about the real world, as in "The soldiers fired at the  women  and  I
saw  several  fall",  where  the referent of "several" depends on our
relatively unreliable knowledge of how the world works.  This is done
by  extracting  inferential information from the basic representation
with common-sense inference  rules,  that  are  themselves  expressed
within the semantic notation.

During  the  last  year,  the  CD  group  has  brought together three
programs  to  implement  MARGIE:       Meaning   Analysis,   Response
Generation  and  Inference  on English. MARGIE is a prototype system,
presently undergoing concurrent development here at Stanford, and  at
the  Istituto  per  gli  studi  semantici  e cognitivi in Castagnola,
Switzerland.

MARGIE's  three  component  programs  (analyzer,   memory/inferencer,
generator)  (a)  analyze English utterances in context into graphs in
the deep conceptual base prescribed  by  Conceptual  Dependency,  (b)
generate   inferences   spontaneously   from  the  graphs  and  build
relational networks which demonstrate an ability to  understand  what
was  said,  and  (c)  generate  responses,  constructed  in this deep
conceptual base, back into surface  (syntax)  networks,  and  finally
back into syntactically correct English sentences.   In addition, the
analyzer  and  generator  may  be  run  coupled  directly   together,
providing  a  paraphraser which paraphrases the meaning of an English
sentence rather than simply its syntactic form.

For example, from the input "John killed Mary by choking  Mary",  the
paraphraser  will return with a number of sentences examples of which
are "John strangled Mary" and "John choked Mary and she died  because
she could not breathe".

In  the  "Inference mode" the MARGIE system takes input such as "John
gave Mary a beating with a stick" and produces a number  of  inferred
output  sentences such as "A stick touched Mary", "Mary became hurt "
and so on.
.begin bib

1.	Goldman, N., Riesbeck, C.,  "A  Conceptually  Based  Sentence
Paraphraser", Stanford Artificial Intelligence Memo AIM-196, May 1973.

2.	Goldman,  N., "Computer Generation of Natural Language from a
Deep Conceptual Base", Ph.D. Thesis in Computer Science,  Stanford
University (forthcoming)

3.	Herskovits,  A.,  "The  generation  of French from a semantic
representation",  Stanford  Artificial  Intelligence  Memo   AIM-212,
October 1973.

4.	Rieger, C., "Conceptual Memory:   A Theory for Processing the
Meaning Content of Natural Language Utterances", Ph.D. Thesis in Computer
Science, Stanford University (forthcoming).

5.	Riesbeck,  C.,  "Computer  Analysis  of  natural  Language in
Context", Ph.D. Thesis in Computer  Science,  Stanford  University
(forthcoming).

6.	Schank, R., Goldman, N., Rieger, C., Riesbeck, C., "Primitive
Concepts  Underlying   Verbs   of   Thought",   Stanford   Artificial
Intelligence Memo AIM-162, Feb. 1972.

7.	Schank,  R.,  Goldman, N., Rieger, C., Riesbeck, C., "MARGIE:
Memory, Analysis, Response  Generation  and  Inference  on  English",
%2Advance  Papers  of  the  Third  International  Joint  Conference  on
Artificial Intelligence,%1 Stanford U., August 1973.

8.	Schank,  R.,  Rieger,  C.,  "Inference   and   the   Computer
Understanding  of Natural Language", Stanford Artificial Intelligence
Memo AIM-197, May 1973.

9.	Schank, R.,  Wilks,  Y.,  "The  Goals  of  Linguistic  Theory
Revisited", Stanford Artificial Intelligence Memo AIM-202, May 1973.

10.	Schank,  R., "Finding the Conceptual Content and Intention in
an Utterance in Natural Language Conversation", %2Advance Papers of the
Second  International  Joint  Conference On Artificial Intelligence%1,
British Comp. Soc., London, 1971.

11.	Schank, R., "Conceptual Dependency:    a  Theory  of  Natural
Language Understanding", %2Cognitive Psychology%1, Vol. 3, No. 4, 1972.

12.	Schank,   R.,  "The  Fourteen  Primitive  Actions  and  Their
Inferences", Stanford Artificial Intelligence Memo AIM-183, February 1973.

13.	Wilks, Y., "Decidability and Natural Language", %2Mind%1, December
1971.

14.	Wilks, Y., %2Grammer, Meaning and the Machine Analysis of
Language%1, Routledge, London, 1972.

15.     Wilks, Y., "The Stanford Machine Translation and Understanding
Project",  in Rustin (ed.), %2Natural Language Processing%1, New York,
1973.

16.	Wilks, Y., "An Artificial  Intelligence  Approach  to  Machine
Translation," Stanford Artificial Intelligence Memo AIM-161, February
1972; to appear in Schank and Colby (eds.), %2Computer Models of Thought
and Language%1, W. H. Freeman, San Francisco, 1973.

17.     Wilks, Y., "Understanding Without Proofs", %2Advanced Papers of
the   Third   International   Joint    Conference    on    Artificial
Intelligence%1, Stanford U., August 1973.

18.	Wilks, Y.,  and  Herskovits,  A., "An Intelligent Analyser and
Generator for Natural  Language,  %2Proceedings  of  the  International
Conference on Computational Linguistics%1, Pisa, 1973.

19.	Wilks, Y.,  "Preference Semantics",
Stanford Artificial Intelligence Memo AIM-206, July 1973; also in
E. Keenan (ed.), %2Proc. 1973 Colloquium
on Formal Semantics  of  Natural  Language%1, Cambridge, U.K., 1974 (to appear).

.end
.SS Programming Languages

There is a strong connection between what you can say and the language
in which you say it.  Advances in artificial intelligence, as well as other
branches of computer science, are frequently linked to advances in
programming languages.  We have found it advantageous to invest a part of
our effort in language development and the corresponding compilers and
run-time packages.

We have already discussed the development of a "hand language" in support
of robotics research [{YON(MANIP)}].  This section discusses more general
programming language developments that have taken place in our laboratory.

Feldman and Gries published an analytical survey of translator (e.g. compiler)
writing systems in 1968 [3].  Donald Knuth continued publication
of a series of texts on computer programming that has become the standard
reference in the field
[4, 5, 6].  He also published reports on language definition schemes [7],
a study of "real world" programming practices [8, summarized in 9] and
an interesting historical study [10].

.begin bib; aimer;

[1] J. Hext, "Programming Languages and Translation", AIM-19, August 1964.

[2] D. Raj Reddy, "Source Language Optimization of FOR-loops", AIM-20, August 1964.

[3] Jerome Feldman and David Gries, "Translator Writing Systems", %2Comm. ACM%1,
February 1968.

[4] Donald E. Knuth, <The Art of Computer Programming, Vol. 1, Fundamental
Algorithms>, Addison-Wesley, Menlo Park, Calif., 1968.

[5] Donald E. Knuth, <The Art of Computer Programming, Vol. 2, Seminumerical
Algorithms>, Addison-Wesley, Menlo Park, Calif., 1969.

[6] Donald E. Knuth, <The Art of Computer Programming, Vol. 3, Sorting
and Searching>, Addison-Wesley, Menlo Park, Calif., 1973.

[7] Donald E. Knuth, "Examples of Formal Semantics", AIM-126, July 1970.

[8] Donald E. Knuth, "An Empirical Study of Fortran in Use", AIM-137, November 1970.

[9] Donald E. Knuth, "An Empirical Study of Fortran Programs, <Software --
Practice and Experience>, Vol. 1, 105-133, 1971.

[10] Donald E. Knuth, "Ancient Babylonian Algorthms", <Comm. ACM>, July 1972.

.end
.sss LISP

LISP is the most widely used language in artificial intelligence research.
The overall design of this programming system was defined in John McCarthy's
1960 article [11].  LISP 1.5, developed initially at MIT [12], became
available on nearly every major computer and remains so today.

Of course, the various versions of "LISP 1.5" turned out to be not quite
compatible.  Even so, Tony Hearn devised a LISP subset that is fairly
portable [17].  This facilitated distribution of his REDUCE system for
symbolic computation [see {YON(SYM)}].

There was an early attempt to design an advanced language called LISP 2 [13, 16].
The implementation of a compiler was to be done by a group at System
Development Corperation.  Unfortunately, they elaborated it to death.

Stanford LISP 1.6 was initially developed in 1966 from an MIT PDP-6 system.
Our staff essentially rewrote the system several times since [18] and
have distributed it through DECUS.  It is currently in use at dozens of
PDP-6 and PDP-10 installations.

A group at U. C. Irvine has substantially augmented Stanford LISP in the
direction of BBN LISP.  The result is a very convenient and powerful
system [19].

One of our groups developed the MLISP compiler [20, 21, 22, 23], which
offers an ALGOL-like syntax on top of all the standard LISP features.
This language is in use by investigators in artificial intelligence
in various parts of this country and at least one place in Europe.

More recently, the same group has been working on a powerful new language called
LISP70 [24].  It allows pattern-directed computation and extensibility,
i.e. the user can add his own rewrite rules for new functions, which
will automatically be merged and ordered in the existing rules.

.begin bib; aimer;

[11] John McCarthy, "Recursive Functions of Symbolic Expressions", <Comm. ACM>,
April 1960.

[12] John McCarthy, et al, <LISP 1.5 Programmer's Manual>, MIT Press, 1962.

[13] John McCarthy, "Storage Conventions in LISP 2", AIM-8, September 1963.

[14] S. R. Russell, "Improvements in LISP Debugging", AIM-10, December 1963.

[15] J. Hext, "An Expression Input Routine for LISP", AIM-18, July 1964.

[16] R. W. Mitchell, "LISP 2 Specifications Proposal", AIM-21, August 1964.

[17] Anthony C. Hearn, "Standard LISP", AIM-90, May 1969.

[18] Lynn Quam, Whitfield Diffie, "Stanford LISP 1.6 Manual", Stanford A. I.
Lab. Operating note SAILON-28.7, 1973 (originally published in 1966).

[19] R. J. Bobrow, R. R. Burton, D. Lewis, "UCI LISP Manual", U. C. Irvine
Information and Computer Science Technical Report No. 21, October 1972.

[20] David C. Smith, "MLISP Users' Manual", AIM-84, January 1969.

[21] David C. Smith, "MLISP", AIM-135, October 1970.

[22] David C. Smith, Horace Enea, "MLISP2", AIM-195, May 1973.

[23] David C. Smith, Horace Enea, "Backtracking in MLISP2", <Advance Papers,
International Joint Conf. on Artificial Intelligence>, Stanford U., August 1973.

[24] L. G. Tesler, Horace Enea, David C. Smith, "The LISP70 Pattern Matching System",
<Advance Papers,
International Joint Conf. on Artificial Intelligence>, Stanford U., August 1973.

.end
.sss FAIL

FAIL is a fast one-pass assembler for PDPα-10 and PDPα-6 machine language.
It was developed initially by Phil Petit in 1968 [25] and the fourth revision
of the manual will be published soon [26].

Compared with MACROα-10, the standard DEC assembler, FAIL uses substantially
more memory, but assembles most programs in about one-fifth the time.
FAIL assembles the entire Stanford A. I. timesharing system (two million
characters) in less than 4 minutes of CPU time on a KA-10 processor.

FAIL provides more powerful macros than MACRO and has ALGOL-like block structure,
permitting local names to be reused in various parts of a program without conflict.

Nearly all our system and utility programming is done in FAIL. It is distributed
through DECUS and is widely used elsewhere.

.begin bib; aimer;

[25] P. M. Petit, "FAIL", Stanford A. I. Lab. Operating Note SAILON-26, 1968.

[26] F. H. G. Wright, "FAIL", Stanford A. I. Memo, in preparation.

.end
.sss SAIL

Members of our staff began work on an ALGOL compiler for the PDP-6 in 1967.
Work continued intermittently through December 1968, when Dan Swinehart put up GOGOL III
[28].

Feldman subsequently guided the development of an extensively revised version
that included his LEAP constructs [29, 30].  The resulting system, now called
SAIL, has undergone a number of subsequent revisions (e.g. [31]) and a new
manual has been written [32].
SAIL is now a rather sophisticated programming
system, offering coroutining, backtracking, context switching, and a number of
other features.

The development of SAIL has been heavily influenced by the needs of our robotics
research.  SAIL is in use in a number of activities here and at many
other installations on the ARPA network.

.begin bib; aimer;

[27] John McCarthy (with 12 others), "ALGOL 60", <Comm. ACM>, May 1960 and
Jan. 1963; <Numerische Mathematik>, March 1960.

[28] Dan Swinehart, "GOGOL III", Stanford A. I. Lab. Operating Note SAILON-48,
December 1968.

[29] Jerome Feldman, Paul Rovner, "The Leap Language Data Structure", <Proc. IFIP
Congress>, 1968.

[30] Jerome Feldman, Paul Rovner, "An ALGOL-based Associative Language", AIM-66,
August 1968; also in <Comm. ACM>, August 1969.

[31] Jerome Feldman, J. Low, D. C. Swinehart, R. H. Taylor, "Recent Developments
in SAIL, an ALGOL-based language for Artificial Intelligence", <Proc. FJCC>, 1972.

[32] Kurt VanLehn (ed.), "SAIL User Manual", AIM-204, July 1973.

.end
.SS Computer Facilities

In support of our research program,
we have developed a very efficient display-oriented timesharing system.
The basic hardware is a PDP-10/PDP-6 dual processor system with 256K words
of core memory, a Librascope swapping disk, an IBM 3330 disk file with
85 million word capacity, and 64 display terminals.

The system is up essentially 24 hours per day, every day; it is not taken
down for preventive maintenance.
It comfortably supports forty-some
jobs with a monitor that is functionally similar to DEC's TOPS-10, though
quite different inside.

The high performance of the computer facility results in part from a
number of technical innovations, both in hardware and software, and
a great deal of hard work.  We have consistently invested about one-third
of our total funding in development of the computer system, and consider
that ratio to be about right.

Equipment acquisition costs have been kept relatively low
by not restricting choices to devices that are "compatible" with
our existing hardware.  Instead, we have selected on a performance/cost basis
and usually done our own interfacing.  The resulting total cost, including
engineering and technician
time, is often as low as one-third the price of "turn-key" devices,
particularly for memories.  Of course, the resulting system has a "mosaic"
quality, with elements representing nearly every manufacturer.  Nevertheless,
it works rather well.

Our current system has the following features.

.begin indent 0,3
1.  It successfully combines real time service (e.g. control of mechanical
arms) with general timesharing [9, 13, 14].  We were the first to do this.

2.  Everyone in our laboratory has a display terminal with full graphics
capability in his office.  This was made possible by their low average cost
(about $2K per terminal).  We employ a video switch to share a limited
number of display generators among a larger number of displays [19].
This idea is being copied in a number of new
display systems elsewhere.

3.  Our display keyboard design uses multiple shift and control keys to provide
both touch-typing of a large character set and powerful interactive control
of editors and other system functions.  This keyboard is now in use at MIT,
Carnegie-Mellon University, and the University of Utah, and other groups
are considering it.

4.  Our teletype text editor, called SOS, was written some time ago (1968),
but still is unsurpassed in its class [11].  It was recently adopted as a
standard by the DECUS PDP-10 users group.

5.  Our new display editor, called "E", is even better.  Words can't describe
it, but see [21, 22].

6.  We have a geometric editor, called GEOMED, for drawing 3-D objects
interactively and viewing them from any perspective [18].

7.  Another family of drawing editors are used to design and check digital
logic circuits and the corresponding printed circuit cards [23].  This
family of programs has been adopted by MIT, CMU, and DEC.

8.  We have developed a news information retrieval service called APE [30].  Our
computer has a connection to an Associated Press newswire and maintains
a file of storys from the last 24 hours.  These storys are indexed
under the words they contain, so that a person can ask for all
the stories that mention, say, "Egypt" and have them displayed immediately.
This service has proven to be very popular with people on the ARPA Network.

9.  We have a document compiler called PUB that handles text justification
with multiple variable-width fonts [20].  If asked, it will automatically
handle section, page, and figure numbering, keep cross-references straight,
generate a table of contents and a sorted index, and other wonderful things.
Pub is in use at nearly all sites that have acquired Xerox Graphics Printers.

.end

.sss Early Development

The concept of a general purpose timesharing system was first proposed
by John McCarthy when he was at MIT.  That proposal led to the systems
developed in Project MAC.  McCarthy also participated in the development
of an early timesharing system at BBN [1].

Shortly after arriving at Stanford in 1962, McCarthy undertook the
development of a display-oriented timesharing system, with support from
the National Science Foundation. That system had 12 display terminals
connected to a PDP-1, with a link to an IBM 7090 [6].  An entertaining
film report summarizes the capabilities of the system [7].

The PDP-1 timesharing system was used
for some early hand-eye experiments with a rather crude television camera
interface [3,4] and a donated prosthetic arm.
The staff who developed the PDP-1 system became the nucleus
of the A. I. Project computer group in 1966, which gave us a head start
on the new system.

.sss Hardware

Over ten years,
total direct expense for computer and experimental equipment (not
including salaries for construction or maintenance) was $2.4 million.
Of this, about $1.6 million was for capital equipment purchases, $400K
for interfacing and spare parts, $200K for IBM disk rental, and $200K
for outside computer time.

Equipment acquisition highlights are as follows.
.begin crbreak; nojust preface 0; select 3; tabs 6,12; indent 0,15; turn on "\";
Date online\Equipment
.select 1;
1966\June\PDP-6, 64K core, 8 Dectape drives, 8 Teletypes
\Oct.\Vidicon camera, Rancho Arm
1967\Nov.\Librascope Disk
1968\Jan.\6 III Displays
\Aug.\Ampex Core (64K)
\Sept.\PDP-10 (KA-10 processor)
1969\Feb.\IBM 2314 Disk
1970\Jun.\3 IMLAC displays
1971\Mar.\Data Disc displays (58 eventually)
\May\Scheinman (Stanford) Arm
\July?\BBN IMP
1972\Jan.\IBM 3330 replaces 2314
\April\Ampex core (128K)
\May\Video Switch
1973\Jan.\Xerox Graphics Printer
.end

Beginning in the summer of 1970, we also undertook the design of a new
high speed processor, known locally as "Foonly", which was to be ten times
as fast as our PDP-10.  The design was completed in early 1973 and featured
a 2K word cache memory, a microcode store that was to be accessible by
timeshared users, and a "Console Computer", which was to be a minicomputer
with display and keyboard.  The Console Computer was to take the place of
the traditional console lights and switches and, since it was to control the
registers and clock of the big machine, could be used to monitor and debug
the latter.

The processor was not fabricated, but some of the ideas in it may be expected
to appear in commercial equipment.  The digital logic design programs mentioned
earlier were developed in support of this effort.

.sss Software

Our first PDP-6 timesharing monitor was the DEC 1.3 Monitor.  Since then,
we have rewritten essentially all of the system, some parts more than once.
We have mostly added features; a number of these have found their way back
into later DEC monitors.  Thus, we are semi-compatible with current TOPS-10
monitors.

An area of major revision in our system is keyboard and display service.  We
devised a "line editor" for displays, that facilitates rapid entry and modification
of lines of text.  Using the keyboards, we can also control various formatting
parameters of the display and can even switch to television, to watch
televised seminars on the Stanford campus.  This service is a fringe benefit of
using standard TV monitors for displays together with a video switch.

In support of the display service, we had to restructure the monitor to provide
free storage allocation for display data.  This free storage feature has proven useful for
a number of other system functions.

We developed a display-oriented debugging package called RAID [16].
Its purpose is similar to DDT, but the display permits more powerful interaction,
such as maintaining displays of selected locations.

When we received the PDP-10 in 1968, we devised a dual processor system that
permits the PDP-10 to be used for both realtime and general timesharing service
and the PDP-6 to be used for realtime only, such as control of arms and (recently)
raster generation for the Xerox Graphics Printer.

We completely rewrote the disk file system in the Monitor, adding redundancy
and read-before-write checking.  Disk files are backed up by a tape archiving
system that gives excellent protection against both operating and programming
errors [24].  We have never had a major file loss attributable to
system hardware or software failure since our file system was installed in 1969.

.turn on "%"
We have developed a resource reservation and allocation system,
called RSL [29], that allows users to "purchase" reservations for subsystems
and a %2service level%1 (a percentage of CPU cycles).
Reservation costs vary with the time of day and are stated in a reusable
pseudo-currency, %2bams%1,
whose abundance is controlled administratively.  The reservation transactions,
enforcement, and accounting are all performed automatically by programs.
This permits persons who need assured services to have them without worrying
about how many other people climb on the system.
.turn off "%"

An IMP was installed fairly early in the life of the ARPA Network and
we wrote
a telnet program to talk to it.  At this point we discovered that the extra
core memory needed
to support this service caused serious system performance degradation.  
As a consequence,
chose not to support network services until after we had a full 256K words
of memory, in the spring of 1972 [25, 26].

Overall we think that our system has yielded excellent returns on the investment,
though it suffers from chronic overloading.  CPU time is the principal
bottleneck.

.begin bib; once fac; indent 0,0;
Note that SAILONs listed below are <Stanford A. I. Lab. Operating
Notes>, which are generally written for laboratory internal use.
The text of most SAILONs is kept in disk files in our [S,DOC] area.  <Working
Notes> are even less formal than SAILONs and usually are kept only in the form
of text files on the disk.  Even so, these files are public and
can be accessed over the ARPA Network [see Appendix A].

.aimer; at "PRO-" ⊂ " Working Note in disk file " ⊃; turn on "#";

[1]  John  McCarthy, S.  Boilen, E. Fredkin, J.C.R. Licklider,
"A  Time-Sharing Debugging  System  for a  Small Computer", <Proc.
AFIPS Conf.> (SJCC), Vol. 23, 1963.

[2]  John McCarthy, F.   Corbato, M.  Daggett, "The  Linking
Segment   Subprogram   Language   and  Linking   Loader   Programming
Languages," <Comm. ACM>, July 1963.

[3]  P. Carah, "A Television Camera Interface for the PDP-1", AIM-34,
June 1965.

[4]  J. Painter, "Utilization of a TV Camera on the PDP-1", AIM-36, September 1965.

[5]  John McCarthy, "Time-sharing Computer Systems", in W. Orr (ed.),
<Conversational Computers>, Wiley, 1966.

[6]  John McCarthy, D. Brian, G. Feldman, J.#Allen, "THOR -- A Display
Based Time-sharing System", <Proc. AFIPS Conf.> (FJCC), Vol. 30, Thompson,
Washington D. C., 1967.

[7]  Art Eisenson, Gary Feldman, "Ellis D. Kropotechev and Zeus, his
Marvelous Time-sharing System", 16mm film, black and white with sound,
15 minutes, March 1967.

[8]  Richard Gruen, W. Weiher, "Rapid Program Generation", <Proc. DECUS
Symposium>, Fall 1968.

[9]  J. A. Moorer, "Dual Processing for the PDP-6/10", <Decuscope>, Vol 8,
No. 3, 1969.

[10]  William Weiher, "Loader Input Format", SAILON-46, October 1968.

[11]  William Weiher, S. Savitzky, "Son of Stopgap", SAILON-50.3, also in
disk file SOS.LES[S,DOC].

[12]  William Weiher, R. Gruen, "RPG -- Rapid Program Generator", SAILON-51,
1968.

[13]  J. A. Moorer, "Stanford A-I Project Monitor Manual:  Chapter I -
Console Commands", SAILON-54.2, September 1970 (revision in preparation).

[14]  J. A. Moorer, "Stanford A-I Project Monitor Manual:  Chapter II -
User Programming", SAILON-55.2, September 1970 (revision in preparation).

[15]  Ted Panofsky, "Stanford A-I Facility Manual", SAILON-56, May 1973.

[16]  Phil Petit, "RAID", SAILON-58.1, February 1970.

[17]  Richard P. Helliwell, "Copy", SAILONα-61.1, May 1971.

[18]  Bruce Baumgart, "GEOMED -- A Geometric Editor", SAILON-68, May 1972.

[19]  Lester Earnest, "Video Switch", SAILONα-69, May 1972.

[20]  Larry Tesler, "PUB, the Document Compiler", SAILON-70, September 1972.

[21]  Dan Swinehart, "TV -- A Display Text Editor", PRO- TVED.DCS[UP,DOC],
December 1971.

[22]  Fred Wright, "Differences between `E' and `TV'", PRO- TV2E.FW[UP,DOC].

[23]  Richard Helliwell, "Stanford Drawing Program", PRO-W[F,RPH].

[24]  Ralph Gorin, "DART -- Dump and Restore Technique", PRO-DART.REG[UP,DOC],
November 1972.

[25]  Andy Moorer, "Telnet Program", PRO-NET.JAM[UP,DOC].

[26]  Dan Swinehart, "FTP -- File Transfer Protocol", PRO-FTP.DCS[UP,DOC].

[27]  Ralph Gorin, "Spooler System Documentation", PRO-SPOOL.REG[UP,DOC].
February 1971.

[28]  Ralph Gorin, "Spelling Checker", PRO-SPELL.REG[UP,DOC].

[29]  Jim Stein, "Automatic Service Level Reservation", PRO-RSL.JHS[UP,DOC].

[30]  Martin Frost, "Reading Associated Press News", SAILON-72, July 1973.

.END
.SS Associated Projects

.turn on "%"
Our ARPA-sponsored research program has benefited from interaction with several
associated but separately supported projects.  In addition to intellectual
interchange, there has been some resource sharing among the projects.
For example, some computer equipment purchases and rentals have been shared
on a %2quid pro quo%1 basis.
.turn off "%"

.sss Higher Mental Functions

The Higher Mental Functions Project, under the leadership of Kenneth Colby,
is supported by the National Institutes of Health.  The overall objectives
are to aid in the solution of certain problems in psychiatry
and psychotherapy.

One line of research involves a computer model of paranoia, called PARRY,
which responds to natural language inquiries [6].  Another involves computer-based
treatment of language difficulties in nonspeaking children [9].  (For this
research, the principal investigator received the 1973 Frieda Fromm-Reichmann
Award from the American Academy of Psychoanalysis.)

.begin bib; aimer;

[1]  Colby, K. M., and Smith, D. C., "Dialogues between Humans and Artificial Belief
Systems", AIM-97, August 1969; also in
<Proc. International Joint Conference on Artificial Intelligence>, 1969.

[2]  Colby, K. M., Tesler, L., and Enea, H. J., "Experiments with a Search Algorithm on the
Data Base of a Human Belief Structure", AIM-94, August 1969.

[3]  Colby, K. M., Hilf, F. D., and Hall, W. A., "A Mute Patient's Experience with 
Machine-Mediated Interviewing", AIM-113, March 1970.

[4]  Colby, K. M., "Mind and Brain, Again",  AIM-116, March, 1970; also in
<Mathematical Biosciences> Vol. 11, 47-52, 1970.

[5]  Colby, K. M., and Smith, D. C., "Computer as Catalxβ| in the Treatment of Nonspeaking
Autistic Children", AIM-120, April 1970.

[6]  Colby, K. M., Weber, S., and Hilf, F. D., "Artificial Paranoia", AIM-125, July
1970; also in <Artificial Intelligence Journal> Vol. 2, No. 1, 1972.

[7]  Colby, K. M., Hilf, F. D., Weber, S., and Kraemer, H. C., "A Resemblance Test for 
the Validation of a Computer Simulation of Paranoid Processes", AIM-156, November
1971.

[8]  Colby, K. M., Hilf, F. D., Weber, S., and Kraemer, H. C., "Turing-like 
Indistinguishability Tests for the Validation of a Computer Simulation of Paranoid
Processes", <Artificial Intelligence Journal> Vol. 3, No. 1, Fall 1972.

[9]  Colby, K. M., "The Rationale for Computer-based Treatment of Language Difficulties in
Nonspeaking Autistic Children", AIM-193, April 1973; also in
<Journal of Autism and Childhood Schizophrenia>, Vol. 3,
254-260, 1973.

[10]  Colby, K. M. and Hilf, F. D., "Multidimensional Analysis in Evaluating a Simulation
of Paranoid Thought", AIM-194, May, 1973.

[11]  Enea, H. J., and Colby, K. M., "Idiolectic Language-Analysis for Understanding
Doctor-Patient Dialogues", <Advance Papers of the Third International Joint
Conference on Artificial Intelligence>, 278-284, 1973.

[12] Hilf, F. D., Colby, K. M., Smith, D. C., Wittner, W., and Hall, W. A., "Machine-
Mediated Interviewing", <Journal of Nervous and Mental Disease>, Vol. 152, No. 4,
1971.

[13]  Hilf, F. D., "Non-Nonverbal Communication and Psychiatric Research", <Archives of
General Psychiatry>, Vol. 27, November 1972.

[14]  Hilf, F. D., "Partially Automated Psychiatric Interviewing -- A Research Tool", 
<Journal of Nervous and Mental Disease>, Vol. 155, No. 6, December 1972.

[15]  Schank, R. C., "The Fourteen Primitive Actions and Their Inferences", AIM-183,
February 1973.

[16]  Schank, R. C., and Rieger, C. J. III, "Inference and Computer Understanding of
Natural Language", AIM-197, May 1973.

[17]  Schank, R. C., and Wilks, Y., "The Goals of Linguistic Theory Revisited", AIM-202,
May 1973.

[18]  Schank, R. C., "The Development of Conceptual Structures in Children", AIM-203,
May, 1973.

[19]  Schank, R. C., Goldman, N., Rieger, C. J. III, and Riesbeck, C., "Margie: Memory,
Analysis, Response Generation and Inference on English", <Advance Papers of the
Third International Joint Conference on Artificial Intelligence>, 255-261, August 1973.

[20]  Schank, R. C., "Identification of Conceptualizations Underlying Natural Language",
in R. Schank and K. Colby (eds.), <Computer Models of Thought and Language>,
W. H. Freeman, San Francisco, 1973.

[21]  Schank, R. C., and Colby, K. M., (eds.), <Computer Models of Thought and Language>, W. H.
Freeman, San Francisco, 1973.

[22]  Smith, D. C., and Enea, H. J., "MLISP2", AIM-195, May 1973.

[23]  Smith, D. C., and Enea, H. J., "Backtracking in MLISP2", <Advance Papers of the 
Third International Joint Conference on Artificial Intelligence>, 677-685, August 1973.

[24]  Tesler, L., Enea, H. J., and Colby, K. M., "A Directed Graph Representation for 
Computer Simulation of Belief Systems", <Mathematical Biosciences>, Vol. 2, 1968.

[25]  Tesler, L. G., Enea, H. J. and Smith, D. C., "The LISP70 Pattern Matching System",
<Advance Papers of the Third International Joint Conference on Artificial 
Intelligence>, 671-676, August 1973.

.end
.sss Digital Holography

In a project lead by Joseph Goodman of the Electrical Engineering
Department and sponsored by the Air Force,
certain techniques for converting holograms into photographic images
were investigated, with potential applications to satellite photography.

One interesting byproduct of this work was the creation of the world's first
photograph taken without lens or pinhole [2].  A hologram was formed
directly on the surface of a vidicon television tube, which was connected
to our computer through a digitizer.  The digitized hologram was then
converted into an image of the original object by computer methods
and displayed on a CRT.

.begin bib

[1]  Joseph Goodman,    "Digital  Image  Formation  from  Electronically
Detected  Holograms,"  in <Proc.    SPIE  Seminar  on Digital  Imaging
Techniques>,    Soc.     Photo-Optical  Instrumentation   Engineering,
Redondo Beach, California, 1967.

[2]  Joseph Goodman,   "Digital  Image  Formation  from  Electronically
Detected Holograms," <Applied Physics Letters>, August 1967.

[3]  A.   Silvestri  and  J.   Goodman,    "Digital  Reconstruction of
Holographic Images",   1968,   NEREM Record,   IEEE,  Vol.   10,  pp.
118-119. 1968.

.end
.sss Sound Synthesis

John Chowning and Leland Smith of the Stanford Music Department
and their students
have developed computer techniques for generating stereophonic and quadraphonic
sounds that can be programmed to move in two and three dimensions
with respect to the listener.  The method controls the distribution and
amplitude of direct and reverberant signals between loudspeakers to
provide the angular and distance information and introduces a Doppler shift
to enhance velocity information [3].

Recently, Chowning made an interesting discovery that
frequency modulation techniques  provide a simple but effective
way to synthesize certain kinds of sounds [6].

Leland Smith has developed a graphics editor capable of handling musical
notation, among other things [7].  A number of commercial groups had previously
tried and failed to solve this problem.

.begin bib; aimer;

[1]  James Beauchamp (with H. Von Foerster)  (eds.), <Music by Computers>,
John Wiley, New York, 1969.

[2]  John M. Chowning, "The Simulation of Moving Sound Sources",
<Proc. Audio Engineering Soc. Convention>, May 1970.

[3]  James  A. Moorer,  "Music  and Computer  Composition", <Comm.  ACM>,
January 1972.

[4]  Leland Smith, "SCORE  -- A Musician's Approach to Computer Music",
<J. Audio Eng. Soc.>, Jan./Feb. 1972.

[5] James A. Moorer, "The Hetrodyne Method of Analysis of Transient
Waveforms", AIM-208, June 1973.

[6]  John M. Chowning, "The Synthesis of Complex Audio Spectra by means
of  Frequency Modulation", <J. Audio Engineering  Society>, September
1973.

[7]   Leland Smith,  "Editing and Printing Music by Computer", <J. Music
Theory>, Fall 1973.

.end
.sss Mars Picture Processing

As in so many areas, John McCarthy was among the first to examine
potential applications of artificial intelligence to planetary exploration [1].

More recently,
under the sponsorship of the National Aeronautics and Space Administration,
Lynn Quam did a dissertation on picture differencing techniques
[2].  The particular set of pictures he worked on was
satellite photographs of Mars containing various geometric and
photometric distortions as well as several kinds of noise.  He successfully
solved the problem of detecting small changes in the planet surface in the presence of all
these extraneous factors.

His system was subsequently applied to pictures of Mars taken
by the Mariner 9 spacecraft while the mission was in progress [3, 4, 5].
A short film shows the interactive display techniques [6].

.begin bib; aimer;

[1] John McCarthy, "Computer Control of a Machine for Exploring Mars",
AIM-14, January 1964.

[2] Lynn H. Quam, "Computer Comparison of Pictures", AIM-144, May 1971.

[3] Lynn H. Quam, et al, "Computer Interactive Picture Processing", AIM-166,
April 1972.

[4] Carl Sagan, et al, "Variable Features on Mars:  Preliminary Mariner
9 Television Results", <Icarus> 17, pp. 346-372, 1972.

[5] Lynn H. Quam, et al, "Mariner 9 Picture Differencing at Stanford",
<Sky and Telescope>, August 1973.

[6] Larry Ward, "Computer Interactive Picture Procession", 16 mm color film
with sound, 8 min., 1972.

.end
.S HEURISTIC PROGRAMMING PROJECT
.MACRO SS(NAME) ⊂ SSNAME←NULL
.BEGIN IF  LINES<25 THEN NEXCOL;
.NEXT SUBSECTION; TURN ON "#{"
.INDENT 2,8; NOJUST; SKIP; SELECT 3
.SUBSECTION!}##NAME
.SELECT 1; SSNAME←"NAME"
.SEND CONTENTS ⊂ SKIP
∩∩3:∂3{SUBSECTION!}##NAME→##{PAGE!}
. ⊃
.END ⊃

The Heuristic Programming Project originated in 1965 under the name
Heuristic DENDRAL.  Its current title reflects a broadening of scope to
include several areas of research related by the common theme of
developing high-performance, intelligent programs for assisting
scientific work.

.SS Summary of Aims and Accomplishments

Heuristic DENDRAL is one of the few examples of a high-performance
intelligent system, sometimes achieving levels of scientific problem
solving not yet achieved by the best human experts, often achieving
levels equal to that of good human performance.  However, the attention
given to the Heuristic DENDRAL performance program as a successful
application of artificial intelligence research has tended to obscure
the more general concerns of the project investigators.  Our aims and
accomplishments have been:

1.  To study and construct detailed information processing models of
processes of scientific inference.  By scientific inference we mean the
inferential process by which a model is constructed to explain a given
set of empirical data.  The Heuristic DENDRAL system is such a model.

2.  To study experimentally the "operating characteristics" and the
effectiveness of different designs (strategies) for the development of
task-specific knowledge in a scientific area.  The Planning Rule
Generator, a program which takes the theory used in hypothesis
verification and produces rules for guiding hypothesis generation, is a
result of this concern [23].  The General Planning Program is
another example [28].

3.  To develop a method for eliciting from an expert the heuristics of
scientific judgment and choice that he is using in the performance of a
complex inference task.  We have designed our problem solving systems so
that the heuristics may be separated from the programs which use them.
By restricting program design to this table-driven form [16] new
heuristics can be easily incorporated.  Heuristic DENDRAL, Meta-DENDRAL,
and the General Planning Program employ this methodology.

4.  To solve real problems in an area of significance to modern science,
and to do so with a level of performance high enough to have a
noticeable impact upon that area of science.  Chemists will agree we
have reached that stage.  For example, the General Planning Program has
been used to analyze mixtures of estrogenic steroids without the need
for gas-chromatographic separation [32].  In the analysis of data
for some classes of compounds Heuristic DENDRAL's performance matches or
exceeds that of a post-doctoral chemist.

5.  To discover the heuristics that form the basis of expert
performance.  The significant problem is not so much tuning a specialist
with new sets of heuristics for new problems as learning how to acquire
these heuristics.  The problem of knowledge acquisition and structuring
by problem solving systems is crucial, and is perhaps the central
problem of AI research today.  In recent years we have made it the main
concern of our project.  The work on automatic theory formation is
focussed on the development of a program called Meta-DENDRAL for
automatic acquisition of a theory of fragmentation processes in mass
spectrometry [33, 34].


6.  To study the representation of knowledge.  Much of Computer Science
can be viewed as a series of programming innovations by means of which
we are moving gradually from a position of having to tell a computer
precisely how we want a problem to be solved to a position of being able
to tell a problem-solving program what we wish done by the computer.
But, what the user wants done always concerns some specific task
environment--some piece of the real world.  For the problem-solving
program to interpret for itself the what, it must have knowledge of the
specific task environment and its behavior.  In other words, the program
needs some kind of theory (formal, informal, heuristic, etc.) of that
environment in terms of which to do its problem solving.  We have seen
in our work that the form in which knowledge about the (DENDRAL) world
is represented is crucial to effective problem solving and to augmenting
the knowledge structure for improved performance.  We have found the
production rule form of knowledge representation to be flexible, easily
understood, manipulable by a computer program, and capable of driving a
complex problem solving system [16, 17, 25, 26].


.cb Survey Articles

The research leading to the implementation of the Heuristic DENDRAL and
Meta-DENDRAL systems has been documented in over thirty publications; a
bibliography is included at the end of this section.  In particular,
[17] and [25] give fairly concise summaries of the Heuristic
DENDRAL research up through 1970, and reference 29 reports on the status
of Meta-DENDRAL as of the middle of 1972.


.cb Most Recent Accomplishments

Since 1970, the most significant accomplishments of the  DENDRAL
research effort have been the design and implementation of
.begin indent 0,3; preface 0;

     1) an exhaustive and irredundant generator of topological graphs,
     thereby extending Heuristic DENDRAL to cyclic structures [30],

     2) a General Planning Program which interprets high resolution mass
     spectral data from complex, biologically interesting molecules
     having a known skeletal substructure [28, 32],

     3) the initial parts of a theory formation program which has
     already been used to infer a theory of mass spectrometry for a
     particular class of molecules [33].
.end

.ss Current Activity

At the present time the Project members are working in the following
task areas:
.begin indent 0,3

1)  Heuristic DENDRAL - Extensions to the Heuristic DENDRAL program
    are aimed at increasing its utility to practicing chemists by
    extending its domain of applicability to a wider class of
    molecules.  This work is now funded by the Biotechnology Resources
    Branch of the National Institutes of Health (Grant No. RR-612-01).

2)  Meta-DENDRAL - Within the domain of mass spectrometry, a theory
    formation program is under development.  The goal is to assist in
    the inference of the theory of fragmentation of molecules in a
    mass spectrometer.

3)  Intelligent Control of Scientific Instruments - The aim of this
    research is to develop programs for intelligent control of a
    data-collecting instrument.  The program makes control decisions by
    reasoning in terms of a theory of the instrumental and physical
    process involved.  This is a problem of importance when time, band
    width, or other constraints limit the amount of data which can be
    gathered for analysis.  Candidate instruments are mass spectrometers
    and nuclear magnetic resonance spectrometers.

4)  Application of AI to the task of computer programming (Automatic
    Programming) - One of the aspects of programming being worked
    upon is debugging.  In a DENDRAL-like fashion, evidence of
    program malfunction (bugs) is "explained" in terms of a model of
    commonly-observed program pathologies.  In another effort, the
    synthesis of portions of systems programs is the subject of a
    Ph.D. thesis project now being formulated.

5)  Application of AI to a new complex task domain of scientific
    interest, viz. protein structure determination from x-ray
    crystallographic data - Work has recently begun to develop heuristic
    programs that will formulate 3-space models of the structure of
    proteins.  The expertise of protein chemists in "fitting" complex
    structures to poorly resolved and/or incomplete data will be extracted
    from experts and used by the program.
.end

.ss Views Expressed by Others Concerning DENDRAL
.begin "WONDERFUL"
. MACRO BEG ⊂ BEGIN INDENT 3,3,3; ⊃; preface 0;
. AT "<" ⊂ "%2"⊃; AT ">" ⊂"%1"⊃; TURN ON "%";

The DENDRAL publications have engendered considerable discussion
and comment among computer scientists and chemists.  Professor H.
Gelernter (SUNY, Stony Brook), at an SJCC 1970 panel of the use of
computers in science gave an extended discussion of the program, in
which he said that it was the first important scientific application
of artificial intelligence.  Dr. W. H. Ware (RAND Corporation) in a
recent article entitled "The Computer in Your Future" in the
collection <Science and Technology in the World of the Future> (A. B.
Bronwell, ed., Wiley Press, 1970) said:
.BEG
     "Thus, much of engineering will be routinized at a high
     level of sophistication, but what about science?  An
     indication of what is coming at a higher level of
     intellectual performance is a computer program called
     Heuristic DENDRAL, which does a task that a physical
     chemist or biologist concerned with organic chemistry does
     repeatedly."
.END

Professor J. Weizenbaum of MIT, in an undergraduate computer science
curriculum proposal for MIT entitled "A First Draft of a Proposal for a
New Introductory Subject in Computer Science (September 1970)", included
Heuristic DENDRAL in his "group 4" series (three lectures) entitled
Great Programs; and he said recently (personal communication),
commenting on recent work and plans,
.BEG
     "I see the work you are now beginning as a step in the
     direction of composing explicit models of just such
     programs (that build expertise in an area).  The
     implications of a success in such an effort are staggering.
     I therefore believe your effort to be worthy of very
     considerable investment of human and financial resources."
.END

In his paper presented at the Sixth International Machine Intelligence
Workshop, Professor Saul Amarel (Rutgers University) used Heuristic
DENDRAL to illustrate a point about programs which use theoretical
knowledge.  He wrote:
.BEG
     "The DENDRAL system provides an excellent vehicle for the
     study of uses of relevant theoretical knowledge in the
     context for formation problems," from "Representations and
     Modeling in Problems of Program Formation", Saul Amarel,
     in <Machine Intelligence 6> (B. Meltzer and D. Michie, eds.)
     Edinburgh University Press (in press).
.END

Professor Donald Michie of the University of Edinburgh includes a
description of Heuristic DENDRAL in his recent paper on "Machines and
the Theory of Intelligence" (<Nature>, 241, pp. 507-512, February 23,
1973):
.beg
     "Mass spectrogram analysis was proposed by Lederberg as a
     suitable task for machine intelligence methods.  The heuristic
     DENDRAL program developed by him and Feigenbaum now outperforms
     post-doctoral chemists in the identification of certain classes
     of organic compounds.  The program is a rich quarrying ground
     for fundamental mechanisms of intelligence, including the
     systematic conjecture of hypotheses, heuristic search, rote
     learning, and deductive and inductive reasoning."
.end

And, in the March, 1973, issue of <Computing Reviews> (pp. 132-133),
Robert Kling of the University of Wisconsin begins his review of
reference 25 with this assessment of DENDRAL:
.beg
     "This brief paper provides an overview of one of the most
     sophisticated applications programs in artificial intelligence."
.end

Dr. T. G. Evans (Air Force Cambridge Research Labs), President of the
ACM SIGART, in introducing a talk on Heuristic DENDRAL at the 1970
FJCC meeting of SIGART, called the program "probably the smartest
program in the world" (and followed this with the interesting
observation that this program had probably received a more sustained
and intense effort than any other single program in the history of the
artificial intelligence field).

At a practical level, a mass spectrometry laboratory at the University
of Copenhagen, headed by Dr. Gustav Schroll, adapted the program to his
facilities there.

.end "WONDERFUL"
.BEGIN BIB;

[1] J. Lederberg, "DENDRAL-64 - A System for Computer
Construction, Enumeration and Notation of Organic Molecules as
Tree Structures and Cyclic Graphs", (technical reports to NASA,
also available from the author and summarized in [12]).
.begin indent 3,7; crbreak; nojust; preface 0;
    (1a) Part I. Notational algorithm for tree structures (1964) CR.57029.
    (1b) Part II. Topology of cyclic graphs (1965) CR.68898.
    (1c) Part III. Complete chemical graphs; embedding rings in trees (1969).
.end

[2] J. Lederberg, <Computation of Molecular Formulas for Mass
Spectrometry>, Holden-Day, Inc. (1964).

[3] J. Lederberg, "Topological Mapping of Organic Molecules",
<Proc. Nat. Acad. Sci.>, 53:1, January 1965, pp.  134-139.

[4] J. Lederberg, "Systematics of organic molecules, graph
topology and Hamilton circuits.  A general outline of the DENDRAL
system."  NASA CR-48899 (1965).

[5] J. Lederberg, "Hamilton Circuits of Convex Trivalent
Polyhedra (up to 18 vertices)", <Am. Math. Monthly>, May 1967.

[6] G. L. Sutherland, "DENDRAL - A Computer Program for
Generating and Filtering Chemical Structures", Stanford Artificial
Intelligence Memo AIM-49, February 1967.

[7] J. Lederberg and E. A. Feigenbaum, "Mechanization of
Inductive Inference in Organic Chemistry", in B. Kleinmuntz (ed)
<Formal Representations for Human Judgment>, Wiley, 1968; also
Stanford Artificial Intelligence Memo AIM-54, August
1967.

[8] J. Lederberg, "Online Computation of Molecular Formulas from
Mass Number"  NASA CR-94977, 1968.

[9] E. A. Feigenbaum and B. G. Buchanan, "Heuristic DENDRAL: A Program
for Generating Explanatory Hypotheses in Organic Chemistry", in
<Proceedings, Hawaii International Conference on System Sciences>,
B. K. Kinariwala and F. F. Kuo (eds), University of Hawaii Press,
1968.

[10] B. G. Buchanan, G. L. Sutherland, and E. A.  Feigenbaum,
"Heuristic DENDRAL: A Program for Generating Explanatory
Hypotheses in Organic Chemistry", in <Machine Intelligence 4>, B.
Meltzer and D. Michie (eds), Edinburgh University Press, 1969;
also Stanford Artificial Intelligence Memo AIM-62, July
1968.

[11] E. A. Feigenbaum, "Artificial Intelligence: Themes in the
Second Decade".  In <Final Supplement to Proceedings of the IFIP68
International Congress>, Edinburgh, August 1968; also Stanford
Artificial Intelligence Memo AIM-67, August 1968.

[12] J. Lederberg, "Topology of Molecules", in <The Mathematical
Sciences - A Collection of Essays>, Committee on Support of
Research in the Mathematical Sciences (COSRIMS), National Academy
of Sciences - National Research Council, M.I.T. Press, 1969, pp.
37-51.

[13] G. Sutherland, "Heuristic DENDRAL: A Family of LISP
Programs", to appear in D. Bobrow (ed), <LISP Applications>; also
Stanford Artificial Intelligence Memo AIM-80, March 1969.

[14] J. Lederberg, G. L. Sutherland, B. G. Buchanan, E.  A.
Feigenbaum, A. V. Robertson, A. M. Duffield, and C.  Djerassi,
"Applications of Artificial Intelligence for Chemical Inference I.
The Number of Possible Organic Compounds: Acyclic Structures
Containing C, H, O and N".  <Journal of the American Chemical
Society>, 91:11, May 21, 1969.

[15] A. M. Duffield, A. V. Robertson, C. Djerassi, B.  G.
Buchanan, G. L. Sutherland, E. A. Feigenbaum, and J.  Lederberg,
"Application of Artificial Intelligence for Chemical Inference II.
Interpretation of Low Resolution Mass Spectra of Ketones".
<Journal of the American Chemical Society>, 91:11, May 21, 1969.

[16] B. G. Buchanan, G. L. Sutherland, E. A.  Feigenbaum, "Toward
an Understanding of Information Processes of Scientific Inference
in the Context of Organic Chemistry", in <Machine Intelligence 5>,
B. Meltzer and D. Michie, (eds), Edinburgh University Press
1970; also Stanford Artificial Intelligence Memo AIM-99, September 1969.

[17] J. Lederberg, G. L. Sutherland, B. G. Buchanan, and E. A.
Feigenbaum, "A Heuristic Program for Solving a Scientific
Inference Problem: Summary of Motivation and Implementation",
Stanford Artificial Intelligence Memo AIM-104, November
1969.

[18] C. W. Churchman and B. G. Buchanan, "On the Design of
Inductive Systems: Some Philosophical Problems", <British Journal
for the Philosophy of Science>, 20, 1969, pp. 311-323.

[19] G. Schroll, A. M. Duffield, C. Djerassi, B. G.  Buchanan, G.
L. Sutherland, E. A. Feigenbaum, and J.  Lederberg, "Application
of Artificial Intelligence for Chemical Inference III.  Aliphatic
Ethers Diagnosed by Their Low Resolution Mass Spectra and NMR
Data", <Journal of the American Chemical Society>, 91:26, December
17, 1969.

[20] A. Buchs, A. M. Duffield, G. Schroll, C. Djerassi, A.  B.
Delfino, B. G. Buchanan, G. L. Sutherland, E. A.  Feigenbaum, and
J. Lederberg, "Applications of Artificial Intelligence For
Chemical Inference. IV. Saturated Amines Diagnosed by Their Low
Resolution Mass Spectra and Nuclear Magnetic Resonance Spectra",
<Journal of the American Chemical Society>, 92, 6831, 1970.

[21] Y.M. Sheikh, A. Buchs, A.B. Delfino, G. Schroll, A.M.
Duffield, C. Djerassi, B.G. Buchanan, G.L. Sutherland, E.A.
Feigenbaum and J. Lederberg, "Applications of Artificial
Intelligence for Chemical Inference V.  An Approach to the
Computer Generation of Cyclic Structures.  Differentiation
Between All the Possible Isomeric Ketones of Composition
C6H10O", <Organic Mass Spectrometry>, 4, 493, 1970.

[22] A. Buchs, A.B. Delfino, A.M. Duffield, C. Djerassi,
B.G. Buchanan, E.A. Feigenbaum and J. Lederberg, "Applications
of Artificial Intelligence for Chemical Inference VI.  Approach
to a General Method of Interpreting Low Resolution Mass Spectra
with a Computer", <Chem. Acta Helvetica>, 53, 1394, 1970.

[23] E.A. Feigenbaum, B.G. Buchanan, and J. Lederberg, "On Generality
and Problem Solving:  A Case Study Using the DENDRAL Program", in
<Machine Intelligence 6>, B. Meltzer and D. Michie, (eds.), Edinburgh
University Press, 1971; also Stanford Artificial Intelligence
Memo AIM-131, August 1970.

[24] A. Buchs, A.B. Delfino, C. Djerassi, A.M. Duffield, B.G. Buchanan,
E.A. Feigenbaum, J. Lederberg, G. Schroll, and G.L. Sutherland, "The
Application of Artificial Intelligence in the Interpretation of Low-
Resolution Mass Spectra", <Advances in Mass Spectrometry>, 5, 314.

[25] B.G. Buchanan and J. Lederberg, "The Heuristic DENDRAL Program
for Explaining Empirical Data", <Proc. IFIP Congress 71>;
also Stanford Artificial Intelligence
Memo AIM-141.

[26] B.G. Buchanan, E.A. Feigenbaum, and J. Lederberg, "A Heuristic
Programming Study of Theory Formation in Science", <Advance Papers of
the Second International Joint Conference on Artificial Intelligence>,
Imperial College, London, September, 1971; also Stanford Artificial
Intelligence Memo AIM-145.

[27] Buchanan, B. G., Duffield, A.M., Robertson, A.V., "An Application
of Artificial Intelligence to the Interpretation of Mass Spectra",
<Mass Spectrometry Techniques and Appliances>, George
W. A. Milne (ed), John Wiley & Sons, 1971, p. 121-77.

[28] D.H. Smith, B.G. Buchanan, R.S. Engelmore, A.M. Duffield, A. Yeo,
E.A. Feigenbaum, J. Lederberg, and C. Djerassi, "Applications of
Artificial Intelligence for Chemical Inference VIII.  An approach to
the Computer Interpretation of the High Resolution Mass Spectra of
Complex Molecules.  Structure Elucidation of Estrogenic Steroids",
<Journal of the American Chemical Society>, 94, 5962-5971, 1972.

[29] B.G. Buchanan, E.A. Feigenbaum, and N.S. Sridharan, "Heuristic
Theory Formation:  Data Interpretation and Rule Formation", in
<Machine Intelligence 7>, Edinburgh University Press, 1972.

[30] Brown, H., Masinter L., Hjelmeland, L., "Constructive Graph
Labeling Using Double Cosets", <Discrete Mathematics> (in press);
also Stanford Computer Science Memo 318, 1972.

[31] B. G. Buchanan, Review of Hubert Dreyfus' "What Computers Can't
Do:  A Critique of Artificial Reason", <Computing Reviews>, January
1973; also Stanford Artificial Intelligence Memo AIM-181, November 1972.

[32] D. H. Smith, B. G. Buchanan, R. S. Engelmore, H. Aldercreutz and
C. Djerassi, "Applications of Artificial Intelligence for Chemical
Inference IX.  Analysis of Mixtures Without Prior Separation as
Illustrated for Estrogens".  <Journal of the American Chemical Society>
(in press).

[33] D. H. Smith, B. G. Buchanan, W. C. White, E. A. Feigenbaum,
C. Djerassi and J. Lederberg, "Applications of Artificial Intelligence
for Chemical Inference X.  Intsum.  A Data Interpretation Program as
Applied to the Collected Mass Spectra of Estrogenic Steroids".
<Tetrahedron>, (in press).

[34] B. G. Buchanan and N. S. Sridharan, "Rule Formation on
Non-Homogeneous Classes of Objects", <Advance Papers of the Third
International Joint Conference on Artificial Intelligence>, Stanford,
California, August, 1973.

.end
.APP ACCESS TO DOCUMENTATION
.turn on "%"

This is a description of how to get copies of publications referenced
in this report.

.cb External Publications

For books, journal articles, or conference papers, first try a technical
library.  If you have difficulty, you might try writing the author directly,
requesting a reprint.  Appendix D lists publications alphabetically by lead author.

.cb Artificial Intelligence Memos

Artificial Intelligence Memos, which carry an "AIM" prefix on their number, are used
to report on research or development results of general interest, including
all dissertations published by the Laboratory.  Appendix B lists the titles
of dissertations; Appendix E gives the abstracts of all A. I. Memos
and instructions for how to obtain copies.  The texts of
some of these reports are kept in our disk file and may be accessed via the
ARPA Network (see below).

.cb Computer Science Reports

Computer Science Reports carry a "STANα-CS-" prefix and report research results
of the Computer Science Department. (All A. I. Memos published since July 1970
also carry CS numbers.)  To request a copy of a CS report, write to:
.begin preface 0; indent 6,6; crbreak; nojust
Documentation Services
Computer Science Department
Stanford University
Stanford, California 94306
.end
The Computer Science Department publishes a monthly abstract of forthcoming
reports that can be requested from the above address.

.cb Film Reports

Several films have been made on research projects.  See Appendix C
for a list of films and procedures for borrowing prints.

.cb Operating Notes

.turn on "%"
Reports that 
carry a SAILON prefix (a strained acronym for %2Stanford A. I. Lab. Operating
Note%1) are semi-formal descriptions of programs or equipment in our laboratory
that are thought to be primarily of internal interest.
The texts of most SAILONS are accessible via the ARPA Network (see below).
Printed copies may be requested from:
.turn off "%"
.begin preface 0; indent 6,6; crbreak; nojust
Documentation Services
Artificial Intelligence Lab.
Stanford University
Stanford, California 94306
.end

.cb Working Notes

Much of our working documentation is not stocked in hard copy form, but
is maintained in the computer disk file.  Such texts that are in public areas
may be accessed from the ARPA Network (see below).  Otherwise, copies may
be requested from the author(s) at the address given above for Operating Notes.

.cb Public File Areas

People who have access to the ARPA Network are welcome to access our public
files.  The areas of principal interest and their contents are a follows:
.begin indent 2,15; preface 0;crbreak; nojust;
[BIB,DOC] bibliographies of various kinds,
[AIM,DOC] texts of a few of our A. I. Memos,
[S,DOC] many of our SAILONs,
[UP,DOC] working notes (quite informal),
[P,DOC] "people-oriented" files, including the lab phone directory.
.end

.cb Network Access

.turn on "%"
To get into our system from the Network, say "%6L NET.GUE%1", which logs
you in as a "network guest".  All commands end with a carriage return.
Our monitor types "." whenever it is
ready to accept a command.  To halt a program that is running, type
<Control>C twice.

If your terminal has both upper and lower case characters, let the monitor
know by saying "%6TTY FULL%1".  If you are at a typewriter terminal, you may
also wish to type "%6TTY FILL%1", which causes extra carriage returns to be inserted so
that the carriage has time to return to the left margin before the next line
begins.

To see the names of all the files in, say, the
[S,DOC] area (where SAILONs are stored), type "%6DIR [S,DOC]%1".  This will
produce a list of files and the dates they were last written.  Among others,
it should list "INTRO.TES", which is an introduction to our timesharing system
(usually obsolescent, alas), written by the programmer whose initials are TES.

To type out the contents of a given file, such as INTRO.TES, say
.preface 0; narrow 2,2; select 6;
TYPE INTRO.TES[S,DOC]
.widen; SELECT 1;
and it will come spewing forth.
To stop the typout, say <Control>C twice and it
will stop after a few lines.  To continue, type "%6CONT%1".  If you wish to
examine selected portions of text files, use the SOS editor in read-only
mode, as described in SOS.LES[S,DOC].
.preface 1;

To log out when you are done, type
.once indent 2; preface 0;
%6K%1 <carriage return>
.turn off "%";

There may be some difficulty with files that employ the full Stanford character
set, which uses some 26 of the ASCII control codes (0 to 37 octal) to
represent special characters.

.CB File Transfer

Files can also be transferred to another site using the File Transfer Protocol.
Documentation on our FTP program is located on our disk file in FTP.DCS[UP,DOC].
No passwords or account numbers are needed to access our FTP from the outside.
.APP THESES

Theses  that  have  been  published  by   the   Stanford   Artificial
Intelligence Laboratory are listed  here.   Several earned degrees at
institutions other than Stanford, as noted.

.BEGIN REF;INDENT 0,0; crbreak; preface 0; turn on "→";
.AT "AIM-" NUM "," NAME "," ⊂ if lines<5 then nexcol else skip;
NAME,→AαIαMα-NUM
. ⊃
AIM-43,
D. Raj. Reddy,
"An Approach to Computer Speech Recognition by Direct Analysis of the Speech Wave",
Ph.D. Thesis in Computer Science,
September 1966.

AIM-46,
S. Persson,
"Some Sequence Extrapolating Programs: a Study of Representation and Modeling in Inquiring Systems",
Ph.D. Thesis in Computer Science, University of California, Berkeley,
September 1966.

AIM-47,
Bruce Buchanan,
"Logics of Scientific Discovery",
Ph.D. Thesis in Philosophy, University of California, Berkeley,
December 1966.

AIM-44,
James Painter,
"Semantic Correctness of a Compiler for an Algol-like Language",
Ph.D. Thesis in Computer Science,
March 1967.

AIM-56,
William Wichman,
"Use of Optical Feedback in the Computer Control of an Arm",
Eng. Thesis in Electrical Engineering,
August 1967.

AIM-58,
Monte Callero,
"An Adaptive Command and Control System Utilizing Heuristic Learning Processes",
Ph.D. Thesis in Operations Research,
December 1967.

AIM-60,
Donald Kaplan,
"The Formal Theoretic Analysis of Strong Equivalence for Elemental Properties",
Ph.D. Thesis in Computer Science,
July 1968.

AIM-65,
Barbara Huberman,
"A Program to Play Chess End Games",
Ph.D. Thesis in Computer Science,
August 1968.

AIM-72,
Donald Pieper,
"The Kinematics of Manipulators under Computer Control",
Ph.D. Thesis in Mechanical Engineering,
October 1968.

AIM-74,
Donald Waterman,
"Machine Learning of Heuristics",
Ph.D. Thesis in Computer Science,
December 1968.

AIM-83,
Roger Schank,
"A Conceptual Dependency Representation for a Computer Oriented Semantics",
Ph.D. Thesis in Linguistics, University of Texas,
March 1969.

AIM-85,
Pierre Vicens,
"Aspects of Speech Recognition by Computer",
Ph.D. Thesis in Computer Science,
March 1969.

AIM-92,
Victor D. Scheinman,
"Design of Computer Controlled Manipulator",
Eng. Thesis in Mechanical Engineering,
June 1969.

AIM-96,
Claude Cordell Green,
"The Application of Theorem Proving to Question-answering Systems",
Ph.D. Thesis in Electrical Engineering,
August 1969.

AIM-98,
James J. Horning,
"A Study of Grammatical Inference",
Ph.D. Thesis in Computer Science,
August 1969.

AIM-106,
Michael E. Kahn,
"The Near-minimum-time Control of Open-loop Articulated Kinematic Chains",
Ph.D. Thesis in Mechanical Engineering,
December 1969.

AIM-121,
Irwin Sobel,
"Camera Models and Machine Perception",
Ph.D. Thesis in Electrical Engineering,
May 1970.

AIM-130,
Michael D. Kelly,
"Visual Identification of People by Computer",
Ph.D. Thesis in Computer Science,
July 1970.

AIM-132,
Gilbert Falk,
"Computer Interpretation of Imperfect Line Data as a Three-dimensional Scene",
Ph.D. Thesis in Electrical Engineering,
August 1970.

AIM-134,
Jay Martin Tenenbaum,
"Accommodation in Computer Vision",
Ph.D. Thesis in Electrical Engineering,
September 1970.

AIM-144,
Lynn H. Quam,
"Computer Comparison of Pictures",
Ph.D. Thesis in Computer Science,
May 1971.

AIM-147,
Robert E. Kling,
"Reasoning by Analogy with Applications to Heuristic Problem Solving: a Case Study",
Ph.D. Thesis in Computer Science,
August 1971.

AIM-149,
Rodney Albert Schmidt,
"A Study of the Real-time Control of a Computer-driven Vehicle",
Ph.D. Thesis in Electrical Engineering,
August 1971.

AIM-155,
Jonathan Leonard Ryder,
"Heuristic Analysis of Large Trees as Generated in the Game of Go",
Ph.D. Thesis in Computer Science,
December 1971.

AIM-163,
Jean M. Cadiou,
"Recursive Definitions of Partial Functions and their Computations",
Ph.D. Thesis in Computer Science,
April 1972.

AIM-173,
Gerald Jacob Agin,
"Representation and Description of Curved Objects",
Ph.D. Thesis in Computer Science,
October 1972.

AIM-174,
Francis Lockwood Morris,
"Correctness of Translations of Programming Languages -- an Algebraic Approach",
Ph.D. Thesis in Computer Science,
August 1972.

AIM-177,
Richard Paul,
"Modelling, Trajectory Calculation and Servoing of a Computer Controlled Arm",
Ph.D. Thesis in Computer Science,
November 1972.

AIM-178,
Aharon Gill,
"Visual Feedback and Related Problems in Computer Controlled Hand Eye Coordination",
Ph.D. Thesis in Electrical Engineering,
October 1972.

AIM-180,
Ruzena Bajcsy,
"Computer Identification of Textured Visiual Scenes",
Ph.D. Thesis in Computer Science,
October 1972.

AIM-188,
Ashok Chandra,
"On the Properties and Applications of Programming Schemas",
Ph.D. Thesis in Computer Science,
March 1973.

AIM-201,
Gunnar Rutger Grape,
"Model Based (Intermediate Level) Computer Vision",
Ph.D. Thesis in Computer Science,
May 1973.

AIM-209,
Yoram Yakimovsky,
"Scene Analysis Using a Semantic Base for Region Growing",
Ph.D. Thesis in Computer Science,
July 1973.

.END
.app FILM REPORTS

Prints  of  the  following films are available for short-term loan to
interested groups without charge.  They may be shown only  to  groups
that have paid no admission fee.  To make a reservation, write to:
.begin indent 4,4; nofill
	Film Services
	Artificial Intelligence Lab.
	Stanford University
	Stanford, California 94305
.end
Alternatively, prints may be purchased at cost (typically $30 to $50)
from:
.begin indent 4,4; nofill
	Cine-Chrome Laboratories
	4075 Transport St.
	Palo Alto, California
	(415) 321-5678
.end

.begin "films"
.ref; indent 0,0; fac;
.count filno inline

.at "⊗" ⊂ if lines<5 then nexcol;
.once indent 0,3; nojust;
.next filno; filno!}.  
. ⊃;

⊗   Art Eisenson and Gary Feldman,
"Ellis D. Kroptechev and Zeus, his Marvelous  Time-sharing  System",
16mm  B&W with sound, 15 minutes,
March 1967.

The advantages of time-sharing over  standard  batch  processing  are
revealed  through the good offices of the Zeus time-sharing system on
a PDP-1 computer.  Our hero, Ellis, is saved from a fate  worse  than
death.   Recommended for mature audiences only.

⊗   Gary Feldman, "Butterfinger",
16mm color with sound,  8  minutes,
March 1968.

Describes  the  state  of  the  hand-eye  system  at  the  Artificial
Intelligence Project in the fall of 1967.  The PDP-6 computer getting
visual information  from  a  television  camera  and  controlling  an
electrical-mechanical  arm  solves  simple  tasks  involving stacking
blocks.  The techniques of recognizing the blocks and their positions
as well as controlling the arm are briefly presented.  Rated "G".

⊗   Raj Reddy, Dave Espar and Art Eisenson,
"Hear Here",
16mm  color with sound, 15 minutes,
March 1969.

Describes the state of the speech recognition project as  of  Spring,
1969.  A discussion of the problems of speech recognition is followed
by two real time demonstrations of the  current  system.   The  first
shows the computer learning to recognize phrases and second shows how
the hand-eye system may be controlled by voice commands.  Commands as
complicated  as  `Pick  up  the  small  block  in  the lower lefthand
corner', are recognized and the tasks are carried out by the computer
controlled arm.

⊗   Gary Feldman and Donald Peiper,
"Avoid",
16mm  silent, color, 5 minutes,
March 1969.

Reports on a computer program written by  D.  Peiper  for  his  Ph.D.
Thesis.    The   problem   is   to   move   the  computer  controlled
electro-mechanical arm through a space filled  with  one  or  more
known  obstacles.   The  program  uses  heuristics for finding a safe
path; the film demonstrates the  arm  as  it  moves  through  various
cluttered environments with fairly good success.

⊗   Richard Paul and Karl Pingle,
"Instant Insanity",
16mm  color, silent, 6 minutes,
August, 1971.

Shows the hand/eye system  solving  the  puzzle %2Instant  Insanity%1.
Sequences  include  finding  and recognizing cubes, color recognition
and object manipulation.  This film was made  to  accompany  a  paper
presented  at  the  1971 International Joint Conference on Artificial
Intelligence in London and may  be  hard  to  understand  without  a
narrator.

⊗   Suzanne Kandra, "Motion and  Vision",
16mm  color,  sound,  22 minutes,
November 1972.

A  technical  presentation  of  three  research projects completed in
1972:  advanced arm control by R. P. Paul [AIM-177],  visual feedback
control  by  A. Gill [AIM-178], and representation and description of
curved objects by G. Agin [AIM-173].

⊗   Larry Ward,
"Computer  Interactive  Picture  Processing",
(MARS Project), 16mm color, sound, 8 min.,
Fall 1972.

This  film  describes an automated picture differencing technique for
analyzing the variable surface features on Mars using  data  returned
by the Mariner 9 spacecraft.  The system uses a time-shared, terminal
oriented PDP-10 computer.  The film proceeds at  a  breathless  pace.
Don't blink, or you will miss an entire scene.

⊗   Richard Paul and Karl Pingle,
"Automated Pump Assembly",
16mm  color, silent (runs at sound speed!), 7 minutes,
April, 1973.

Shows  the  hand-eye system assembling a simple pump, using vision to
locate the pump  body  and  to  check  for  errors.   The  parts  are
assembled  and screws inserted, using some special tools designed for
the arm.  Some titles are included to help explain the film.

⊗   Terry Winograd, "Dialog with a robot",
 16mm black and white, silent, 20 minutes,
(made at MIT), 1971.

Presents  a   natural  language   dialog  with   a  simulated   robot
block-manipulation system.   The dialog is  substantially the same as
that in %2Understanding Natural Language%1 (T. Winograd,  Academic Press,
1972).  No explanatory or narrative material is on the film.

.end "films"

.app EXTERNAL PUBLICATIONS
     
Articles and books by Project members  are listed here alphabetically
by  lead  author.    Only  publications  following  the  individual's
affiliation with the Project are given.

.begin ref;
.COUNT exref TO 200
.AT "⊗" ⊂ IF LINES<3 THEN NEXCOL; NEXT EXREF; (EXREF&".  ") ⊃

⊗Agin, Gerald J., Thomas O. Binford, "Computer Description of
Curved Objects", <Proceedings of the Third International Joint
Conference on Artificial Intelligence>, Stanford University, August
1973.

⊗Allen, John, David Luckham, "An Interactive Theorem-Proving Program"
in Bernard Meltzer and Donald Michie (eds.), <Machine Intelligence 5>,
Edinburgh University Press, 1970.

⊗Ashcroft, Edward, Zohar Manna, "Formalization of Properties of
Parallel Programs", <Machine Intelligence 6>, Edinburgh Univ. Press,
1971.

⊗Ashcroft, Edward, Zohar Manna, "The Translation of `Go To' Programs
to `While' Programs", <Proc. IFIP Congress 1971>.

⊗Ashcroft, Edward, Zohar Manna, Amir Pnueli, "Decidable Properties
of Monodic Functional Schemas", <J. ACM>, July 1973.

⊗Bajcsy, Ruzena, "Computer Description of Textured Scenes", <Proc.
Third Int. Joint Conf. on Artificial Intelligence>, Stanford U.,
1973.

⊗Beauchamp, James, H. Von Foerster (eds.), <Music by Computers>,
John Wiley, New York, 1969.

⊗Becker, Joseph, "The Modeling of Simple Analogic and Inductive
Processes in a Semantic Memory System", <Proc. International Conf.
on Artificial Intelligence>, Washington, D.C., 1969.

⊗Biermann, Alan, Jerome Feldman, "On the Synthesis of
Finite-state Machines from Samples of Their Behavior", <IEEE
Transactions on Computers>, Vol. C-21, No. 6, pp. 592-596, June 1972.

⊗Biermann, Alan, "On the Inference of Turing Machines from Sample
Computations", <Artificial Intelligence J.>, Vol. 3, No. 3, Fall 1972.

⊗Binford, Thomas O., "Sensor Systems for Manipulation", in E.
Heer (Ed.), <Remotely Manned Systems>, Calif. Inst. of Technology,
1973.

⊗Binford, Thomas, Jay M. Tenenbaum, "Computer Vision",
<Computer (IEEE)>, May 1973.

⊗Bracci, Giampio, Marco Somalvico, "An Interactive Software System
for Computer-aided Design: An Application to Circuit Project", <Comm.
ACM>, September 1970.

⊗Buchanan, Bruce, Georgia Sutherland, "Heuristic Dendral: A Program
for Generating Hypotheses in Organic Chemistry", in Donald Michie
(ed.), <Machine Intelligence 4>, American Elsevier, New York, 1969.

⊗Buchanan, Bruce, Georgia Sutherland, Edward Feigenbaum, "Rediscovering
some Problems of Artificial Intelligence in the Context of Organic
Chemistry", in Bernard Meltzer and Donald Michie (eds), <Machine
Intelligence 5>, Edinburgh University Press, 1970.

⊗Buchanan, Bruce, T. Headrick, "Some Speculation about Artificial
Intelligence and Legal Reasoning", <Stanford Law Review>, November
1970.

⊗Buchanan, Bruce, A. M. Duffield, A. V. Robertson, "An Application
of Artificial Intelligence to the Interpretation of Mass Spectra",
in <Mass Spectrometry Techniques and Appliances>, George W.
Milne (ed), John Wiley & Sons, 1971.

⊗Buchanan, Bruce, Edward Feigenbaum, Joshua Lederberg, "A
Heuristic Programming Study of Theory Formation in Science", <Proc.
Second International Joint Conference on Arificial Intelligence
(2IJCAI)>, British Computer Society, Sept. 1971.

⊗Buchanan, Bruce, Joshua Lederberg, "The Heuristic DENDRAL
Program for Explaining Empirical Data", <Proc. IFIP Congress 1971>.

⊗Buchanan, Bruce, E. A. Feigenbaum, and N. S. Sridharan, "Heuristic
Theory Formation: Data Interpretation and Rule Formation", in
<Machine Intelligence 7>, Edinburgh University Press, 1972.

⊗Buchanan, Bruce G., "Review of Hubert Dreyfus' `What Computers Can't
Do': A Critique of Artificial Reason", <Computing Reviews>, January
1973.

⊗Buchanan, Bruce, N. S. Sridharan, "Analysis of Behavior of
Chemical Molecules: Rule Formation on Non-Homogeneous Classes of
Objects", <Proceedings of the Third International Joint Conference on
Artificial Intelligence>, Stanford University, August 1973.

⊗Buchs, A., A. Delfino, A. Duffield, C. Djerassi, B. Buchanan, E.
Feigenbaum, J. Lederberg, "Applications of Artificial
Intelligence for Chemical Inference VI. Approach to a General
Method of Interpreting Low Resolution Mass Spectra with a Computer",
Helvetica Chemica Acta, 53:6, 1970.

⊗Buchs, A., A. Duffield, G. Schroll, Carl Djerassi, A.
Delfino, Bruce Buchanan, Georgia Sutherland, Edward Feigenbaum, Joshua
Lederberg, "Applications of Artificial Intelligence for Chemical
Inference IV. Saturated Amines Diagnosed by their Low Resolution
Mass Spectra and Nuclear Magnetic Resonance Spectra", <J. Amer.
Chem. Soc.>, 92:23, November 1970.

⊗Cadiou, Jean M., Zohar Manna, "Recursive Definitions of Partial
Functions and their Computations", <ACM SIGPLAN Notices>, Vol. 7, No.
1, January 1972.

⊗Campbell, John, "Algebraic Computation of Radiative Corrections for
Electron-Proton Scattering", <Nuclear Physics>, Vol. B1, pp.
238-300, 1967.

⊗Campbell, Anthony Hearn and J. A., "Symbolic Analysis of Feynman
Diagrams by Computer", <Journal of Computational Physics> 5,
280-327, 1970.

⊗Chowning, John M., "The Simulation of Moving Sound Sources",
<Proc. Audio Engineering Soc. Convention>, May 1970.

⊗Chowning, John M., "The Synthesis of Complex Audio Spectra by means
of Frequency Modulation", <J. Audio Engineering Society>, September
1973.

⊗Churchman, C., Bruce Buchanan, "On the Design of Inductive
Systems: Some Philosophical Problems", <British Journal for the
Philosophy of Science>, 20, 1969, pp. 311-323.

⊗Colby, Kenneth, David Smith, "Dialogues between Humans and
Artificial Belief Systems", <Proc. International Conference on
Artificial Intelligence>, Washington, D.C., 1969.

⊗Colby, Kenneth, Larry Tesler, Horace Enea, "Experiments with
a Search Algorithm for the Data Base of a Human Belief System",
<Proc. International Conference on Artificial Intelligence>,
Washington, D.C., 1969.

⊗Colby, Kenneth Mark, "The Rationale for Computer-Based Treatment of
Language Difficulties in Nonspeaking Autistic Children", <Journal of
Autism and Childhood Schizophrenia>, Vol. 3, 254-260, 1970.

⊗Colby, Kenneth, "Mind and Brain Again", <Mathematical Biosciences>, Vol.
11, 47-52, 1970.

⊗Colby, Kenneth, Sylvia Weber, Franklin Hilf, "Artificial Paranoia",
<J. Art. Int.>, Vol. 2, No. 1, 1971.

⊗Colby, Kenneth, F. Hilf, S. Weber, H. C.
Kraemer, "Turing-like Indistinguishability Tests for the Validation
of a Computer Simulation of Paranoid Processes", <Artificial
Intelligence J.>, Vol. 3, No. 3, Fall 1972.

⊗Colby, Kenneth M., "The Rationale for Computer-based Treatment of
Language Difficulties in Nonspeaking Autistic Children", <Journal of
Autism and Childhood Schizophrenia>, Vol. 3, 254-260, 1973.

⊗Dobrotin, Boris M., Victor D. Scheinman, "Design of a Computer
Controlled Manipulator for Robot Research", <Proc. Third Int. Joint
Conf. on Artificial Intelligence>, Stanford U., 1973.

⊗Duffield, Alan, A. Robertson, Carl Djerassi, Bruce Buchanan, G.
Sutherland, Edward Feigenbaum, Joshua Lederberg, "Application
of Artificial Intelligence for Chemical Interference II.
Interpretation of Low Resolution Mass Spectra of Ketones", <J. Amer.
Chem. Soc.>, 91:11, May 1969.

⊗Enea, Horace, Kenneth Mark Colby, "Idiolectic Language-Analysis
for Understanding Doctor-Patient Dialogues", <Proceedings of the
Third International Joint Conference on Artificial Intelligence>,
Stanford University, August 1973.

⊗Falk, Gilbert, "Scene Analysis Based on Imperfect Edge Data", <Proc.
2IJCAI>, Brit. Comp. Soc., Sept. 1971.

⊗Falk, Gilbert, "Interpretation of Imperfect Line Data as a
Three-dimensional Scene", <Artificial Intelligence J.>, Vol. 3, No.
2, 1972.

⊗Feigenbaum, Edward, "Information Processing and Memory", in <Proc.
Fifth Berkeley Symposium on Mathematical Statistics and Probability>,
Vol. 4, U.C. Press, Berkeley, 1967.

⊗Feigenbaum, Edward, Joshua Lederberg, Bruce Buchanan, "Heuristic
Dendral", <Proc. International Conference on System Sciences>,
University of Hawaii and IEEE, University of Hawaii Press, 1968.

⊗Feigenbaum, Edward, "Artificial Intelligence: Themes in the Second
Decade", <Proc. IFIP Congress>, 1968.

⊗Feigenbaum, Edward, Bruce Buchanan, Joshua Lederberg, "On
Generality and Problem Solving: A Case Study using the DENDRAL
Program", <Machine Intelligence 6>, Edinburgh Univ. Press, 1971.

⊗Feldman, Jerome, D. Gries, "Translator Writing Systems",
<Comm. ACM>, February 1968.

⊗Feldman, Jerome, P. Rovner, "The Leap Language Data
Structure", <Proc. IFIP Congress>, 1968.

⊗Feldman, Jerome, "Machine Intelligence, review of Numbers I-III of
the Machine Intelligence series", <Information and Control>, 14,
490-492, 1969.

⊗Feldman, Jerome, "Towards Automatic Programming", <Preprints of
NATO Software Engineering Conference>, Rome, Italy, 1969.

⊗Feldman, Jerome, Paul Rovner, "An Algol-based Associative
Language", <Comm. ACM>, August 1969.

⊗Feldman, Jerome, Gary Feldman, G. Falk, Gunnar Grape, J. Pearlman,
I. Sobel, and J. Tenenbaum, "The Stanford Hand-Eye Project",
<Proc. International Conf. on Artificial Intelligence>, Washington,
D.C., 1969.

⊗Feldman, Jerome, "Getting a Computer to See Simple Scenes", <IEEE
Student Journal>, Sept. 1970.

⊗Feldman, Jerome, Alan Bierman, "A Survey of Grammatical
Inference", <Proc. International Congress on Pattern Recognition>,
Honolulu, January 1971, also in S, Watanbe (ed.), <Frontiers of
Pattern Recognition>, Academic Press, 1972.

⊗Feldman, Jerome, Robert Sproull, "System Support for the
Stanford Hand-eye System", <Proc. 2IJCAI>, Brit. Comp. Soc., Sept.
1971.

⊗Feldman, Jerome, et al, "The Use of Vision and Manipulation to
Solve the `Instant Insanity' Puzzle", <Proc. 2IJCAI>, Brit. Comp.
Soc., Sept. 1971.

⊗Feldman, Jerome, "Some Decidability Results on Grammatical
Inference and Complexity", <Information and Control>, Vol. 20, No.
3, pp. 244-262, April 1972.

⊗Feldman, Jerome, J. Low, D. Swinehart, R. Taylor,
"Recent Developments in SAIL, an ALGOL-based language for Artificial
Intelligence", <Proc. Fall Joint Computer Conference>, 1972.

⊗Floyd, Robert, "Toward Interactive Design of Correct Programs",
<Proc. IFIP Congress 1971>.

⊗Garland, Stephan J., David Luckham, "Translating Recursive Schemes
into Program Schemes", <ACM SIGPLAN Notices>, Vol. 7, No. 1, January 1972.

⊗Garland, Stephan J., David C. Luckham, "Program Schemes,
Recursion Schemes, and Formal Languages", <J. Computer and System
Sciences>, Vol. 7, No. 2, April 1973.

⊗Gips, James, "A New Reversible Figure", <Perceptual & Motor
Skills>, 34, 306, 1972.

⊗Goodman, Joseph, "Digital Image Formation from Electronically
Detected Holograms", <Applied Physics Letters>, August 1967.

⊗Goodman, Joseph, "Digital Image Formation from Electronically
Detected Holograms", in <Proc. SPIE Seminar on Digital Imaging
Techniques>, Soc. Photo-Optical Instrumentation Engineering,
Redondo Beach, California, 1967.

⊗Gruen, Richard, William Weiher, "Rapid Program Generation", <Proc.
DECUS Symposium>, Fall 1968.

⊗Hearn, Anthony, "Computation of Algebraic Properties of Elementary
Particle Reactions Using a Digital Computer", <Comm. ACM>, 9, pp.
573-577, August, 1966.

⊗Hearn, Anthony, "REDUCE, A User-Oriented Interactive System for
Algebraic Simplification", <Proc. ACM Symposium on Interactive
Systems for Experimental Applied Mathematics>, August 1967.

⊗Hearn, Anthony, "The Problem of Substitution", <Proc. IBM Summer
Institute on Symbolic Mathematics by Computer>, July 1968.

⊗Hearn, Anthony, "Applications of Symbol Manipulation in
Theoretical Physics", <Comm. ACM>, August 1971.

⊗Hilf, Franklin, Kenneth Colby, David Smith, W. Wittner,
William Hall, "Machine-Mediated Interviewing", <J. Nervous & Mental
Disease>, Vol. 152, No. 4, 1971.

⊗Hilf, Franklin, "Non-Nonverbal Communication and Psychiatric
Research", <Archives of General Psychiatry>, Vol. 27, November 1972.

⊗Hilf, Franklin, "Partially Automated Psychiatric Research Tool",
<J. Nervous and Mental Disease>, Vol. 155, No. 6, December 1972.

⊗Hueckel, Manfred, "An Operator which Locates Edges in Digitized
Pictures", <JACM>, January 1971.

⊗Hueckel, Manfred H., "A Local Visual Operator which Recognizes
Edges and Lines", <J. ACM>, October 1973.

⊗Ito, T., "Note on a Class of Statistical Recognition Functions",
<IEEE Trans. Computers>, January 1969.

⊗Kahn, Michael, Bernard Roth, "The Near-minimum-time Control of Open-loop
Articulated Kinematic Chains", <Trans. ASME>, Sept. 1971.

⊗Kaplan, Donald, "Some Completeness Results in the Mathematical Theory
of Computation", <ACM Journal>, January 1968.

⊗Kaplan, Donald, "Regular Expressions and the Completeness of Programs",
<J. Comp. & System Sci.>, Vol. 3, No. 4, 1969.

⊗Katz, Shmuel, Zohar Manna, "A Heuristic Approach to Program
Verification", <Proceedings of the Third International Joint
Conference on Artificial Intelligence>, Stanford University, August
1973.

⊗Kieburtz, Richard B., David Luckham, "Compatibility and
Complexity of Refinements of the Resolution Principal", <SIAM J.
Comput.>, 1972.

⊗Kieburtz, Richard, David Luckham, "Compatability and Complexity of
Refinements of the Resolution Principle", <SIAM J. on Computing>,
1-4, 1973.

⊗Kling, Robert, "A Paradigm for Reasoning by Analogy", <Proc. 2IJCAI>,
Brit. Comp. Soc., Sept. 1971.

⊗Knuth, Donald E., <The Art of Computer Programming, Vol. 2,
Seminumerical Algorithms>, Addison-Wesley, Menlo Park, Calif., 1969.

⊗Knuth, Donald E., "An Empirical Study of FORTRAN Programs", <Software
-- Practice and Experience>, Vol. 1, 105-133, 1971.

⊗Knuth, Donald E., "Ancient Babylonian Algorithms", <Comm. ACM>, July
1972.

⊗Knuth, Donald E., <The Art of Computer Programming, Vol. 3, Sorting
and Searching>, Addison-Wesley, Menlo Park, Calif., 1973.

⊗Lederberg, Joshua, "Hamilton Circuits of Convex Trivalent Polyhedra",
<American Mathematical Monthly> 74, 522, May 1967.

⊗Lederberg, Joshua, Edward Feigenbaum, "Mechanization of
Inductive Inference in Organic Chemistry", in B. Kleinmuntz (ed.),
<Formal Representation of Human Judgment>, John Wiley, New York,
1968.

⊗Lederberg, Joshua, "Topology of Organic Molecules", National
Academy of Science, <The Mathematical Sciences: a Collection of
Essays>, MIT Press, Cambridge, 1969.

⊗Lederberg, Joshua, Georgia Sutherland, Bruce Buchanan, Edward
Feigenbaum, A. Robertson, A. Duffield, Carl Djerassi,
"Applications of Artificial Intelligence for Chemical Inference I.
The Number of Possible Organic Compounds: Acyclic Structures
Containing C, H, O, and N", <J. Amer. Chem. Soc.>, 91:11, May 1969.

⊗Lederberg, Joshua, Georgia Sutherland, Bruce Buchanan, Edward
Feigenbaum, "A Heuristic Program for Solving a Scientific Inference
Problem: Summary of Motivation and Implementation", in M. Mesarovic
(ed.), <Theoretical Approaches to Non-numerical Problem Solving>,
Springer-Verlag, New York, 1970.

⊗London, Ralph, "Correctness of a Compiler for a LISP Subset", <ACM
SIGPLAN Notices>, Vol. 7, No. 1, January 1972.

⊗Luckham, David, "Refinement Theorems in Resolution Theory", <Proc.
1968 IRIA Symposium in Automatic Deduction>, Versailles, France,
Springer-Verlag, 1970.

⊗Luckham, David, D. Park and M. Paterson, "On Formalised
Computer Programs", <J. Comp. & System Sci.>, Vol. 4, No. 3,
June 1970.

⊗Luckham, David, Nils Nilsson, "Extracting Information from
Resolution Proof Trees", <Artificial Intelligence Journal>, Vol. 2,
No. 1, pp. 27-54, June 1971.

⊗Luckham, David C., "Automatic Problem Solving", <Proceedings of the
Third International Joint Conference on Artificial Intelligence>,
Stanford University, August 1973.

⊗Manna, Zohar, "Properties of Programs and the First Order
Predicate Calculus", <J. ACM>, Vol. 16, No. 2, April 1969.

⊗Manna, Zohar, "The Correctness of Programs", <J. System and
Computer Sciences>, Vol. 3, No. 2, May 1969.

⊗Manna, Zohar, John McCarthy, "Properties of Programs and
Partial Function Logic" in Bernard Meltzer and Donald Michie (eds.),
<Machine Intelligence 5>, Edinburgh University Press, 1970.

⊗Manna, Zohar, "The Correctness of Non-Deterministic Programs",
<Artificial Intelligence Journal>, Vol. 1, No. 1, 1970.

⊗Manna, Zohar, "Termination of Algorithms Represented as
Interpreted Graphs", <AFIPS Conference Proc. (SJCC)>, Vol. 36, 1970.

⊗Manna, Zohar, "Second-order Mathematical Theory of Computation",
<Proc. ACM Symposium on Theory of Computing>, May 1970.

⊗Manna, Zohar, Amir Pnueli, "Formalization of Properties of
Functional Programs", <J. ACM>, Vol. 17, No. 3, July 1970.

⊗Manna, Zohar, R. Waldinger, "Toward Automatic Program
Synthesis", <Comm. ACM>, March 1971.

⊗Manna, Zohar, "Mathematical Theory of Partial Correctness", <J.
Comp. & Sys. Sci.>, June 1971.

⊗Manna, Zohar, S. Ness, J. Vuillemin, "Inductive Methods for
Proving Properties of Programs", <ACM SIGPLAN Notices>, Vol. 7, No.
4, January 1972.

⊗Manna, Zohar, J. Vuillemin, "Fixpoint Approach to the Theory of
Computation", <Comm. ACM>, July 1972.

⊗Manna, Zohar, "Program Schemas", in <Currents in the Theory of
Computing> (A. V. Aho, Ed.), Prentice-Hall, Englewood Cliffs, N.
J., 1973.

⊗Manna, Zohar, Stephen Ness, Jean Vuillemin, "Inductive Methods for
Proving Properties of Programs", <Comm. ACM>, August 1973.

⊗Manna, Zohar, "Automatic Programming", <Proceedings of the Third
International Joint Conference on Artificial Intelligence>, Stanford
University, August 1973.

⊗Manna, Zohar, <Introduction to Mathematical Theory of
Computation>, McGraw-Hill, New York, 1974.

⊗McCarthy, John, "Towards a Mathematical Theory of Computation", in
<Proc. IFIP Congress 62>, North-Holland, Amsterdam, 1963.

⊗McCarthy, John, "A Basis for a Mathematical Theory of Computation",
in P. Biaffort and D. Hershberg (eds.), <Computer Programming and
Formal Systems>, North-Holland, Amsterdam, 1963.

⊗McCarthy, John, S. Boilen, E. Fredkin, J.C.R. Licklider,
"A Time-Sharing Debugging System for a Small Computer", <Proc.
AFIPS Conf.> (SJCC), Vol. 23, 1963.

⊗McCarthy, John, F. Corbato, M. Daggett, "The Linking
Segment Subprogram Language and Linking Loader Programming
Languages", <Comm. ACM>, July 1963.

⊗McCarthy, John, "Problems in the Theory of Computation", <Proc. IFIP
Congress 1965>.

⊗McCarthy, John, "Time-Sharing Computer Systems", in W. Orr (ed.),
<Conversational Computers>, Wiley, 1966.

⊗McCarthy, John, "A Formal Description of a Subset of Algol", in T.
Steele (ed.), <Formal Language Description Languages for Computer Programming>,
North-Holland, Amsterdam, 1966.

⊗McCarthy, John, "Information", <Scientific American>, September
1966.

⊗McCarthy, John, "Computer Control of a Hand and Eye", in <Proc.
Third All-Union Conference on Automatic Control (Technical
Cybernetics)>, Nauka, Moscow, 1967 (Russian).

⊗McCarthy, John, D. Brian, G. Feldman, and J. Allen, "THOR -- A
Display Based Time-Sharing System", <Proc. AFIPS Conf.> (FJCC), Vol. 30,
Thompson, Washington, D.C., 1967.

⊗McCarthy, John, James Painter, "Correctness of a Compiler for
Arithmetic Expressions", Amer. Math. Soc., <Proc. Symposia in
Applied Math., Math. Aspects of Computer Science>, New York, 1967.

⊗McCarthy, John, "Programs with Common Sense", in Marvin Minsky
(ed.), <Semantic Information Processing>, MIT Press, Cambridge, 1968.

⊗McCarthy, John, Lester Earnest, D. Raj. Reddy, Pierre Vicens, "A
Computer with Hands, Eyes, and Ears", <Proc. AFIPS Conf.> (FJCC),
1968.

⊗McCarthy, John, Patrick Hayes, "Some Philosophical Problems from the
Standpoint of Artificial Intelligence", in Donald Michie (ed.),
<Machine Intelligence 4>, American Elsevier, New York, 1969.

⊗Milner, Robin, "An Algebraic Definition of Simulation between
Programs", <Proc. 2IJCAI>, Brit. Comp. Soc., Sept. 1971.

⊗Milner, Robin, "Implementatiion and Application of Scott's Logic
for Computable Functions", <ACM SIGPLAN NOTICES>, Vol. 7, No. 1, January 1972.

⊗Milner, Robin, Richard Weyhrauch, "Proving Compiler Correctness
in a Mechanized Logic", <Machine Intelligence 7>, Edinburgh
University Press, 1972.

⊗Montanari, Ugo, "Continuous Skeletons from Digitized Images",
<JACM>, October 1969.

⊗Montanari, Ugo, "A Note on Minimal Length Polygonal Approximation
to a Digitized Contour", <Comm. ACM>, January 1970.

⊗Montanari, Ugo, "On Limit Properties in Digitization Schemes",
<JACM>, April 1970.

⊗Montanari, Ugo, "Separable Graphs, Planar Graphs and Web
Grammars", <Information and Control>, May 1970.

⊗Montanari, Ugo, "Heuristically Guided Search and Chromosome
Matching", <J. Artificial Intelligence>, Vol. 1, No. 4, December
1970.

⊗Montanari, Ugo, "On the Optimal Detection of Curves in Noisy
Pictures", <Comm. ACM>, May 1971.

⊗Moorer, James A., "Dual Processing for the PDP-6/10", <Decuscope>,
Vol. 8, No. 3, 1969.

⊗Moorer, James A., "Music and Computer Composition", <Comm. ACM>,
January 1972.

⊗Nevatia, Ramakant, Thomas O. Binford, "Structured Descriptions
of Complex Objects", <Proceedings of the Third International Joint
Conference on Artificial Intelligence>, Stanford University, August
1973.

⊗Nilsson, Nils, <Problem-solving Methods in Artificial
Intellegence>, McGraw-Hill, New York, 1971.

⊗Paul, Richard, G. Falk, Jerome Feldman, "The Computer
Representation of Simply Described Scenes", <Proc. 2nd Illinois
Graphics Conference>, Univ. Illinois, April 1969.

⊗Paul, Richard, Gilbert Falk, Jerome Feldman, "The Computer
Description of Simply Described Scenes", in <Pertinent Concepts in
Computer Graphics>, J. Neivergelt and M. Faiman (eds.), U.
Illinois Press, 1969.

⊗Paul, Richard, "Trajectory Control of a Computer Arm", <Proc.
2IJCAI>, Brit. Comp. Soc., Sept. 1971.

⊗Pingle, Karl, J. Singer, and W. Wichman, "Computer Control of a
Mechanical Arm through Visual Input", <Proc. IFIP Congress> 1968,
1968.

⊗Pingle, Karl, "Visual Perception by a Computer", <Automatic
Interpretation and Classification of Images>, Academic Press, New
York, 1970.

⊗Pingle, Karl, J. Tenenbaum, "An Accomodating Edge Follower",
<Proc. 2IJCAI>, Brit. Comp. Soc., Sept. 1971.

⊗Quam, Lynn, Robert Tucker, Botond Eross, J. Veverka and Carl
Sagan, "Mariner 9 Picture Differencing at Stanford", <Sky and
Telescope>, August 1973.

⊗Reddy, D. Raj., "Segmentation of Speech Sounds", <J. Acoust. Soc.
Amer.>, August 1966.

⊗Reddy, D. Raj., "Phoneme Grouping for Speech Recognition", <J. Acoust.
Soc. Amer.>, May 1967.

⊗Reddy, D. Raj., "Pitch Period Determination of Speech Sounds", <Comm.
ACM>, June 1967.

⊗Reddy, D. Raj., "Computer Recognition of Connected Speech", <J. Acoust.
Soc. Amer.>, August 1967.

⊗Reddy, D. Raj., "Computer Transcription of Phonemic Symbols", <J.
Acoust. Soc. Amer.>, August 1968.

⊗Reddy, D. Raj., "Consonantal Clustering and Connected Speech
Recognition", <Proc. Sixth International Congress on Acoustics>,
Vol. 2, pp. C-57 to C-60, Tokyo, 1968.

⊗Reddy, D. Raj., Ann Robinson, "Phoneme-to-Grapheme Translation of
English", <IEEE Trans. Audio and Electroacoustics>, June 1968.

⊗Reddy, D. Raj., Pierre Vicens, "Procedure for Segmentation of
Connected Speech", <J. Audio Eng. Soc.>, October 1968.

⊗Roth, Bernard, "Design, Kinematics, and Control of Computer-controlled
Manipulators", <Proc. 6th All Union Conference on New Problems in
Theory of Machines & Mechanics>, Leningrad, Jan. 1971.

⊗Sagan, Carl, J. Lederberg, E. Levinthal, L. Quam, R. Tucker, et al,
"Variable Features on Mars:
Preliminary Mariner 9 Television Results", <Icarus 17>, pages
346-372, 1972.

⊗Samuel, Arthur, "Studies in Machine Learning Using the Game of
Checkers, II-Recent Progress", <IBM Journal>, November 1967.

⊗Schank, Roger, Larry Tesler, "A Conceptual Parser for Natural
Language", <Proc. International Joint Conference on Artificial
Intelligence>, Washington, D.C., 1969.

⊗Schank, Roger, "Finding the Conceptual Content and Intention in an
Utterance in Natural Language Conversation", <Proc. 2IJCAI>, Brit.
Comp. Soc., 1971.

⊗Schank, Roger, "Conceptual Dependency: a Theory of Natural Language
Understanding", <Cognitive Psychology>, Vol 3, No. 4, 1972.

⊗Schank, Roger C., Neil M. Goldman, "Theoretical Considerations in
Text Processing", <Conf. Proc. Computer Text Processing and Scientific
Research (1972)>, O.N.R., Pasadena, Calif., March 1973.

⊗Schank, Roger C., Neil Goldman, Charles J. Rieger III, Chris
Riesbeck, "MARGIE: Memory, Analysis, Response Generation and
Inference on English", <Proceedings of the Third International Joint
Conference on Artificial Intelligence>, Stanford University, August
1973.

⊗Schank, Roger C., Kenneth Colby (eds), <Computer Models of Thought
and Language>, W. H. Freeman, San Francisco, 1973.

⊗Schroll, G., A. Duffield, Carl Djerassi, Bruce Buchanan, G.
Sutherland, Edward Feigenbaum, Joshua Lederberg, "Applications
of Artificial Intelligence for Chemical Inference III. Aliphatic
Ethers Diagnosed by Their Low Resolution Mass Spectra and NMR Data",
<J. Amer. Chem. Soc.>, 91:26, December 1969.

⊗Sheikh, Y., A. Buchs, A Delfino, Bruce Buchanan, G. Sutherland,
Joshua Lederberg, "Applications of Artificial Intelligence for
Chemical Inference V. An Approach to the Computer Generation of
Cyclic Structures. Differentiation Between All the Possible
Isometric Ketones of Composition C6H10O", <Organic Mass
Spectrometry>, Vol. 4 pp.493-501, 1970.

⊗Silvestri, Anthony, Joseph Goodman, "Digital Reconstruction of
Holographic Images", 1968 NEREM Record, IEEE, Vol. 10, pp.
118-119. 1968.

⊗Slagle, James, Carl Farrell, "Experiments in Automatic Learning
for a Multiputpose Heuristic Program", <Comm. ACM>, February 1971.

⊗Smith, D. H., B. G. Buchanan, R. S. Engelmore, A. M. Duffield, A. Yeo,
E. A. Feigenbaum, J. Lederberg, C. Djerassi, "Applications of
Artificial Intelligence for Chemical Inference VIII. An approach to
the Computer Interpretation of the High Resolution Mass Spectra of
Complex Molecules. Structure Elucidation of Estrogenic Steroids",
<Journal of the American Chemical Society>, 94, 5962-5971, 1972.

⊗Smith, David Canfield, Horace J. Enea, "Backtracking in
MLISP2", <Proceedings of the Third International Joint Conference on
Artificial Intelligence>, Stanford University, August 1973.

⊗Smith, Leland, "SCORE -- A Musician's Approach to Computer Music",
<J. Audio Eng. Soc.>, Jan./Feb. 1972.

⊗Smith, Leland, "Editing and Printing Music by Computer", <J. Music
Theory>, Fall 1973.

⊗Sobel, Irwin, "On Calibrating Computer Controlled Cameras for
Perceiving 3-D Scenes", <Proc. Third Int. Joint Conf. on Artificial
Intelligence>, Stanford U., 1973.

⊗Sridharan, N., "Search Strategies for the Task of Organic Chemical
Synthesis", <Proceedings of the Third International Joint Conference
on Artificial Intelligence>, Stanford University, August 1973.

⊗Sullivan, S. Brodsky and J., "W-Boson Contribution to the
Anomalous Magnetic Moment of the Muon", <Phys Rev> 156, 1644, 1967.

⊗Sutherland, Georgia, G. W. Evans, G. F.Wallace, <Simulation
Using Digital Computers>, Prentice-Hall, Engelwood Cliffs, N.J.,
1967.

⊗Tenenbaum, Jay, et al, "A Laboratory for Hand-eye Research",
<Proc. IFIP Congress>, 1971.

⊗Tesler, Larry, Horace Enea, Kenneth Colby, "A Directed Graph
Representation for Computer Simulation of Belief Systems", <Math.
Bio.> 2, 1968.

⊗Tesler, Lawrence G., Horace J. Enea, David C. Smith, "The
LISP70 Pattern Matching System", <Proceedings of the Third
International Joint Conference on Artificial Intelligence>, Stanford
University, August 1973.

⊗Waterman, Donald, "Generalization Learning Techniques for Automating
the Learning of Heuristics", <J. Artificial Intelligence>, Vol. 1,
No. 1/2.

⊗Weyhrauch, Richard, Robin Milner, "Program Semantics and
Correctness in a Mechanized Logic", <Proc. USA-Japan Computer
Conference>, Tokyo, 1972.

⊗Wilkes, Yorick, "Semantic Considerations in
Text Processing", <Conf. Proc. Computer Text Processing and Scientific
Research (1972)>, O.N.R., Pasadena, Calif., March 1973.

⊗Wilks, Yorick, "The Stanford Machine Translation and Understanding
Project", in Rustin (ed.) <Natural Language Processing>, New York,
1973.

⊗Wilks, Yorick, "Understanding Without Proofs", <Proceedings of the
Third International Joint Conference on Artificial Intelligence>,
Stanford University, August 1973.

⊗Wilks, Yorick, Annette Herskovits, "An Intelligent Analyser and
Generator of Natural Language", <Proc. Int. Conf. on Computational
Linguistics>, Pisa, Italy, <Proceedings of the Third International
Joint Conference on Artificial Intelligence>, Stanford University,
August 1973.

⊗Wilks, Yorick, "An Artificial Intelligence Approach to Machine Translation",
in Schank and Colby (eds.), <Computer Models of Thought
and Language>, W. H. Freeman, San Francisco, 1973.

⊗Yakimovsky, Yoram, Jerome A. Feldman, "A Semantics-Based
Decision Theoretic Region Analyzer", <Proceedings of the Third
International Joint Conference on Artificial Intelligence>, Stanford
University, August 1973.

.end
.begin "aimab"
.app                    A. I. MEMO ABSTRACTS

In the listing  below, there are up  to three numbers given  for each
Artificial Intelligence
Memo: an  "AIM" number on the left,  a "CS" (Computer Science) number
in the middle, and a  NTIS stock number (often beginning "AD...")  on
the right.  If there is no "*" to the left of the AIM number, then
it is in stock at Stanford at this writing and may be requested from:
.bc indent 3,6;
	Documentation Services
	Artificial Intelligence Laboratory
	Stanford University
	Stanford, California 94305
.end
Alternatively, if there is an NTIS number given, then the report
may be ordered using that number from:
.bc indent 3,6;
	National Technical Information Service
	P. O. Box 1553
	Springfield, Virginia 22151
.end
If there is no NTIS number given then they may or may not have the report.
In requesting copies in this case, give them both
the "AIM-" and "CS-nnn" numbers, with the latter
enlarged into  the form "STAN-CS-yy-nnn",  where "yy" is the  last
two  digits of  the year  of publication.

Memos that are also Ph.D. theses are so marked below and may be ordered from:
.bc indent 3,6;
	University Microfilm
	P. O. Box 1346
	Ann Arbor, Michigan 48106
.end
For people with access to  the ARPA Network, the texts of  some A. I.
Memos are  stored online in the Stanford  A. I. Laboratory disk file.
These are designated  below by "Diskfile:  <file name>" appearing  in
the header.  See Appendix A for directions on how to access such files.

.end "aimab"

.begin "aimac"

.at "*AIM-" AINO "," CSNO "," ADNO "," AUTHORS """" TITLE """"; ⊂
.IF LINES<5 THEN NEXCOL ELSE SKIP;
.CRBREAK PREFACE 0; NOJUST; TURN ON "←→"
*αAαIαMα-AINO←CSNO→ADNO
AUTHORS
.SELECT 3
TITLE,
.SELECT 1;
. ⊃
.at "AIM-" AINO "," CSNO "," ADNO "," AUTHORS """" TITLE """"; ⊂
.IF LINES<5 THEN NEXCOL ELSE SKIP;
.CRBREAK PREFACE 0; NOJUST; TURN ON "←→"
αAαIαMα-AINO←CSNO→ADNO
AUTHORS
.SELECT 3
TITLE,
.SELECT 1;
. ⊃

.AT "Thesis:" type "," ⊂ select 2
αTαhαeαsαis:  type,
.select 1; ⊃

.AT "pages," moyer "."; ⊂
αpαaαgαes, moyer.
.fac;crspace; preface 1; turn off "←→"; ⊃

.TURN OFF "%"
AIM-1,,,
John McCarthy,
"Predicate Calculus with `Undefined' as a Truth-value"
5 pages, March 1963.

The  use  of  predicate  calculus  in  the  mathematical  theory   of
computation and the problems involved in interpreting their values.

AIM-2,,,
John McCarthy,
"Situations, Actions, and Causal Laws"
11 pages, July 1963.

A formal theory is given concerning  situations,  causality  and  the
possibility  and effects of actions is given.  The theory is intended
to be used by the Advice Taker, a computer program that is to  decide
what  to  do  by  reasoning.   Some  simple  examples  are  given  of
descriptions of situations and deductions that certain goals  can  be
achieved.
                                                                          
AIM-3,,,
Fred Safier,
"`The Mikado' an an Advice Taker Problem"
4 pages, July 1963.

The situation of the Second Act of `The Mikado' is analyzed from  the
point  of  view  of  Advice  Taker formalism.  This indicates defects
still present in the language.

*AIM-4,,,
Horace Enea,
"Clock Function for LISP 1.5"
2 pages, August 1963.

This paper describes a clock function for LISP 1.5.

AIM-5,,,
Horace Enea, Dean Wooldridge,
"Algebraic Simplication"
2 pages, August 1963.

Herein described are proposed and effected changes and  additions  to
Steve Russell's Mark IV Simplify.

*AIM-6,,,
Dean Wooldridge,
"Non-printing Compiler"
2 pages, August 1963.

A  short  program  which redefines parts of the LISP 1.5 compiler and
suppresses compiler print out (at user's option) is described.

AIM-7,,,
John McCarthy,
"Programs With Common Sense"
7 pages, September 1963.

Interesting  work  is  being  done  in programming computers to solve
problems which require a  high  degree  of  intelligence  in  humans.
However,  certain  elementary  verbal  reaesoning processes so simple
they can be carried out by any non-feeble-minded human have yet to be
simulated  by  machine  programs.

This paper will discuss  programs to manipulate in a  suitable formal
language  (most  likely  a part  of  the  predicate calculus)  common
instrumental statements.    The  basic program  will  draw  immediate
conclusions  from a  list of  premises.   These  conclusions will  be
either  declarative  or  imperative sentences.    When  an imperative
sentence is deduced the program takes a corresponding  action.  These
actions may  include printing sentences,  moving  sentences on lists,
and  reinitiating  the  basic  deduction  process  on  these   lists.

Facilities will  be  provided for  communication with  humans in  the
system via  manual intervention and display  devices connected to the
computer.

*AIM-8,,,
John McCarthy,
"Storage Conventions in LISP 2"
? pages, September 1963.

Storage conventions and a basic set  of  functions  for  LISP  2  are
proposed.  Since  the  memo  was written, a way  of supplementing the
features of this system with the unique  storage  of  list  structure
using  a  hash  rule  for  computing  the  address in a separate free
storage area for lists has been found.

*AIM-9,,,
C. M. Williams,
"Computing Estimates for the Number of Bisections of an NxN
Checkerboard for N Even"
9 pages, December 1963.

This memo gives empirical justification for the assumption  that  the
number   of  bisections  of  an  NxN  (N  even)  checkerboard  is
approximately given by the binomial coefficient (A, A/2) where 2A  is
the length of the average bisecting cut.

AIM-10,,,
Stephan R. Russell,
"Improvements in LISP Debugging"
3 pages, December 1963.

Experience with  writing large  LISP progrrams  and helping  students
learning LISP  suggests that spectacular improvements  can be made in
this area.   These improvements are partly  an elimination of  sloppy
coding in  LISP 1.5, but  mostly an  elaboration of DEFINE,  the push
down  list backtrace, and  the current tracing  facility.  Experience
suggests that these improvements would reduce the  number of computer
runs to debug a program a third to a half.

AIM-11,,,
Dean Wooldridge, Jr.,
"An Algebraic Simplify Program in LISP"
57 pages, December 1963.

A program  which performs  `obvious' (non-controversial)  simplifying
transformations  on  algebraic expressions  (written  in  LISP prefix
notation) is described.   Cancellation of inverses and  consolidation
of sums  and products are  the basic accomplishments of  the program;
however, if  the user desires to do so, he may request the program to
perform  special tasks,  such  as  collect common  factors  from  the
products  in sums  or expand  products.   Polynomials are  handled by
routines which take advantage of the special form by polynomials;  in
particular, division  (not cancellation) is  always done in  terms of
polynomials.  The program (run  on the  IBM 7090) is  slightly faster
than a human; however, the computer  does not need to check its  work
by repeating the  simplification.

Although the program  is usable -- no bugs  are known to exist  -- it
is  by no  means a  finished project.   A  rewriting of  the simplify
system is  anticipated;  this will  eliminate  much of  the  existing
redundancy  and  other  inefficiency,     as  well  as  implement  an
identity-recognizing scheme.
AIM-12,,,
Gary Feldman,
"Documentation of the MacMahon Squares Problem"
4 pages, January 1964.

An exposition  of  the MacMahon  Squares problem  together with  some
`theoretical'  results on  the nature  of its  solutions and  a short
discussion  of  an  ALGOL  program  which  finds  all  solutions  are
contained herein.

AIM-13,,,
Dean E. Wooldridge,
"The New LISP System (LISP l.55)"
4 pages, February 1964.

The new LISP system  is described.  Although differing  only slightly
it is thought to be an improvement on the old system.

AIM-14,,,
John McCarthy,
"Computer Control of a Machine for Exploring Mars"
6 pages, January 1964.

Landing a 5000 pound package on Mars that  would spend a year looking
for  life  and  making other  measurements  has  been  proposed.   We
believe that this  machine should be a  stored program computer  with
sense and  motor organs and  that the machine  should be mobile.   We
discuss   the  following  points:
.bs
1.  Advantages of a computer controlled system.

2. What the computer should be like.

3. What we  can feasible do  given the present state  of work
   on artificial intelligence.

4. A  plan  for carrying out  research in computer controlled
   experiments that will make the Mars machine  as  effective
   as possible.
.end

AIM-15,,,
Mark Finkelstein, Fred Safier,
"Axiomatization and Implementation"
6 pages, June 1964.

An example  of a typical  Advice-Taker axiomatization of  a situation
is given,   and the situation is programmed  in LISP as an indication
of how the Advice-Taker could  be expected to  react.  The  situation
chosen is the play of a hand of bridge.

AIM-16,,,
John McCarthy,
"A Tough nut for Proof Procedures"
3 pages, July 1964.

It  is  well  known  to  be  impossible   to  tile  with  dominoes  a
checkerboard  with  two  opposite  corners  deleted.   This  fact  is
readily stated in the first  order predicate calculus, but the  usual
proof which involves a parity  and counting argument does not readily
translate  into predicate calculus.  We  conjecture that this problem
will be very difficult for programmed proof procedures.

AIM-17,,,
John McCarthy,
"Formal Description of the Game of Pang-Ke"
2 pages, July 1964.

The game of Pang-Ke is formulated in  a first-order-logic in order to
provide grist  for the Advice-Taker Mill.   The memo does not explain
all the terms used.

AIM-18,,,
Jan Hext,
"An Expression Input Routine for LISP"
5 pages, July 1964.

The expression input  routine is a  LISP function, Mathread [  ] with
associated   definitions,  which   reads   in  expressions   such  as
(A+3-F(X,Y,Z)).   Its  result is  an  equivalent S-expression.    The
syntax of  allowable expressions  is given,  but (unlike  ALGOL's) it
does  not  define  the  precedence of  the  operators;  nor  does the
program carry out any explicit syntax analysis.   Instead the program
parses  the expression  according to  a set  of  numerical precedence
values, and reports if it finds any symbol out of context.

*AIM-19,,,
Jan Hext,
"Programming Languages and Translation"
14 pages, August 1964.

A notation  is suggested  for defining  the syntax  of a language  in
abstract form,   specifying only its semantic constituents.  A simple
language is presented in this form and its semantic  definition given
in  terms of  these constituents.    Methods are  then developed  for
translating  this language,  first into LISP  code and  from there to
machine code, and for proving that the translation is correct.

AIM-20,,,
D. Raj. Reddy,
"Source Language Optimization of For-loops"
37 pages, August 1964.

Program execution time can  be reduced, by a considerable  amount, by
optimizing  the `For-loops' of Algol  programs.  By  judicious use of
index registers  and  by  evaluating all  the  sub-expressions  whose
values are not altered within  the `For-loop',  such optimization can
be achieved.

In  this project we  develop an algorithm to  optimize Algol programs
in list-structure form  and generate a  new source language  program,
which  contains the `desired  contents in  the index registers'  as a
part  of  the   For-clause  of  the   For-statement  and   additional
statements  for   evaluating   the  same   expressions  outside   the
`For-loop'  This  optimization is  performed only  for  the innermost
`For-loops'.

The program is written entirely in LISP.  Arrays may have  any number
of  subscripts.    Further   array  declarations  may  have  variable
dimensions.   (Dynamic allocation  of storage.) The  program does not
try to  optimize  arithmetic expressions.    (This has  already  been
extensively investigated.)

AIM-21,,,
R. W. Mitchell,
"LISP 2 Specifications Proposal"
12 pages, August 1964.

Specifications  for  a  LISP 2  system  are  proposed.    The  source
language is  basically Algol 60 extended  to include list processing,
input/output and language extension facilities.  The system  would be
implemented  with a  source  language translator  and optimizer,  the
output  of which  could be  processed by  either an interpreter  or a
compiler.   The  implementation is  specified  for a  single  address
computer with  particular reference to an IBM  7090 where necessary .

Expected  efficiency   of  the   system   for  list   processing   is
significantly greater than the  LISP 1.5 compiler.  For  execution of
numeric  algorithms  the  systems should  be  be  comparable to  many
current "algebraic" compilers.  Some familiarity with LISP, 1.5 Algol
and the IBM 7090 is assumed.

AIM-22,,,
Richard Russell,
"Kalah -- the Game and the Program"
13 pages, September 1964.

A description of  Kalah and the Kalah program,  including sub-routine
descriptions and operating instructions.

AIM-23,,,
Richard Russell,
"Improvements to the Kalah Program"
12 pages, September 1964.

Recent improvements to the  Kalah program are listed, and  a proposal
for speeding up the program by a factor of three is discussed.

AIM-24,,,
John McCarthy,
"A Formal Description of a Subset of ALGOL"
43 pages, September 1964.

We describe  Microalgol, a  trivial subset  of Algol,  by means of  an
interpreter.  The  notions of abstract  syntax and  of `state of
the computation'  permit a  compact description  of  both syntax  and
semantics.  We  advocate an extension of this technique  as a general
way of describing programming language.

AIM-25,,,
Richard Mansfield,
"A Formal System of Computation"
7 pages, September 1964.

We  discuss  a  tentative  axiomatization  for  a  formal  system  of
computation  and  within this  system we  prove  certain propositions
about  the  convergence  of  recursive  definitions  proposed  by  J.
McCarthy.

AIM-26,,,
D. Raj. Reddy,
"Experiments on Automatic Speech Recognition by a Digital Computer"
19 pages, October 1964.

Speech sounds  have in  the past  been investigated  with the aid  of
spectographs,   vo-coders  and  other  analog   devices.    With  the
availability of digital computers  with improved i-o devices such  as
Cathode  Ray tubes  and analog  digital converters,  it has  recently
become  practicable to employ  this powerful tool in  the analysis of
speech sounds.

Some papers have appeared in the recent  literature reporting the use
of  computers in the  determination of the  fundamental frequency and
for vowel recognition.  This paper discusses the details  and results
of a  preliminary investigation conducted  at Stanford.   It includes
various  aspects of  speech sounds  such as  waveforms of  vowels and
consonants;  determination of  a  fundamental  of the  wave;  Fourier
(spectral) analysis of the  sound waves format determination,  simple
vowel recognition  algorithm  and  synthesis of  sounds.    All  were
obtained by the use of a digital computer.

AIM-27,,,
John McCarthy,
"A Proof-checker for Predicate Calculus"
7 pages, March 1965.

A program  that  checks proofs  in J.  A.  Robinson's formulation  of
predicate calculus  has been programmed in LISP  1.5.  The program is
available in CTSS  at Project  MAC and  is also available  as a  card
deck.  The program is used for class exercises at Stanford.

AIM-28,,,
John McCarthy,
"Problems in the Theory of Computation"
7 pages, March 1965.

The purpose  of this  paper is to  identify and  discuss a number  of
theoretical  problems  whose solutions  seem feasible  and  likely to
advance the practical art of computation.  The problems that  will be
discussed  include  the  following:

1.   Semantics of programming languages.   What  do  the  strings  of
symbols  representing  computer  programs,  statements, declarations,
labels,  etc.,  denote?     How  can  the  semantics  of  programming
languages be described formally?

2.  Data spaces.   What  are  the spaces  of data  on which  computer
programs act and how are they built up up from simpler spaces?

3.  How can time dependent and simultaneous processes be described?

4.     Speed  of  computation.  What  can  be  said  about  how  much
computation is required to carry out certain processes?

5.  Storage of  information.  How can information be stored  so that
items identical or similar to a given item can be retrieved?

6.  Syntax directed computation.   What is the appropriate domain for
computations  described   by  productions   or  other   data   format
recognizers?

7.    What are  the appropriate  formalisms for  writing
proofs that computer programs are equivalent?

8.   In the  view of  Godel's theorem that  tells us that  any formal
theory of  computation  must  be  incomplete, what  is  a  reasonable
formal system  that will enable  us to prove that  programs terminate
in practical cases?

AIM-29,,,
Charles M. Williams,
"Isolation of Important Features of a Multitoned Picture"
9 pages, January 1965.

A roughly successful attempt is made to  reduce a multi-toned picture
to  a  two-toned  (line  drawing)  representation  capable  of  being
recognized by a human being.

AIM-30,,,
Edward A. Feigenbaum, Richard W. Watson,
"An Initial Problem Statement for a Machine Induction Research
 Project"
8 pages, April 1965.

A brief description is given of a  research project presently getting
under  way.   This project  will study   induction by  machine, using
organic chemistry  as  a task  area.    Topics for  graduate  student
research related to the problem are listed.

AIM-31,,,
John McCarthy,
"Plans for the Stanford Artificial Intelligence Project"
17 pages, April 1965.

The following is  an excerpt from a  proposal to ARPA and  gives some
of the project plans for the near future.

AIM-32,,,
Harry Ratchford,
"The 138 Analog Digital Converter"
9 pages, May 1965.

A discussion of  the programming and hardware characteristics  of the
analog  to digital converter  on the  PDP-1 is given;  several sample
programs are also presented.

AIM-33,,,
Barbara Huberman,
"The Advice Taker and GPS"
8 pages, June 1965.

.OI
Using the formalism  of the Newell-Shaw-Simon General  Problem Solver
to solve  problems expressed in McCarthy's  Advice Taker formalism is
discussed.   Some  revisions  of  the  formalism  of <can> and <cause>
described in AI Memo 2 are proposed.

AIM-34,,,
Peter Carah,
"A Television Camera Interface for the PDP-1"
8 pages, June 1965.

This paper is a  discussion of several methods for  the connection of
a  television camera to  the PDP-1 computer.   Three  of these methds
are discussed  in  detail and  have  in common  that  only a  36  bit
portion  of  any  horizontal  scanning  line may  be  read  and  this
information  is read  directly  into  the  working registers  of  the
computer.  The fourth  involves a  data  channel to  read information
directly into the core memory of the computer, and is  mentioned only
in passing.   The  major concepts  and some of  the details  of these
methods are due to Marvin Minsky.

*AIM-35,,,
Fred Safier,
"Simple Simon"
17 pages, June 1965.

SIMPLE SIMON  is a  program which  solves the  problem of finding  an
object satisfying  a predicate from a list of  facts.  It operates by
backward  chaining.   The  rules  of  procedure  and  heuristics  are
discussed and the structure of the program is outlined.

AIM-36,,,
James Painter,
"Utilization of a TV Camera on the PDP-1"
6 pages, September 1965.

A description of  the programming required  to utilize the  TV camera
connected to the PDP-1 and of the initial collection of programs.

*AIM-37,,,
Knut Korsvold,
"An on Line Algebraic Simplification Program"
36 pages, November 1965.

We describe  an on-line  program for  algebraic simplification.   The
program  is  written in  LISP 1.5  for  the Q-32  computer  at System
Development Corporation  in Santa  Monica, California.   The  program
has  in  its entirety  been  written  and  debugged from  a  teletype
station at Stanford University.
AIM-38,,,
Donald A. Waterman,
"A Filter for a Machine Induction System"
19 pages, January 1966.

This  report  contains  current ideas  about  the  Machine  Induction
Research  Project, and attempts  to more  clearly define some  of the
problems involved.    In  particular, the  on-line  data  acquisition
problem, the  filter, and the inductive  inference problem associated
with the filter are discussed in detail.

AIM-39,,,
Karl Pingle,
"A Program to Find Objects in a Picture"
22 pages, January 1966.

A program  is described  which traces  around objects  in a  picture,
using  the picture scanner attached  to the PDP-1  computer, and fits
curves to the edges.

AIM-40, CS-38, AD662880,
John McCarthy, James Painter,
"Correctness of a Compiler for Arithmetic Expressions"
13 pages, April 1966.

This is a preprint of a paper given  at the Symposium of Mathematical
Aspects  of  Computer Science  of the  American  Mathematical Society
held April 7  and  8, 1966.  It contains  a proof of the  correctness
of a compiler for arithmetic expressions.

*AIM-41,,,
Phil Abrams, Dianna Rode,
"A Proposal for a Proof-checker for Certain Axiomatic Systems"
10 pages, May 1966.

A proposed design  for a proof-checker  to operate on  many axiomatic
domains is presented.   Included are descriptions of the organization
and operation of the program to be written for the PDP-6.

AIM-42,,,
Karl Pingle,
"A Proposal for a Visual Input Routine"
11 pages, June 1966.

Some comments are  made on the characteristics believed  desirable in
the next  eye for the Stanford Artificial  Intelligence Project and a
proposal is given for a program to input scenes using the eye.

*AIM-43, CS-49, SS640-836,
D. Raj. Reddy,
"An Approach to Computer Speech Recognition by Direct Analysis of the
 Speech Wave"
Thesis: Ph.D. in Computer Science,
144 pages, September 1966.

A system  for  obtaining a  phonemic transcription  from a  connected
speech  sample  entered into  the  computer by  a  microphone  and an
analog-to-digital  converter  is  described.    A  feature-extraction
program  divides the  speech  utterance  into segments  approximately
corresponding  to phonemes, determine pitch periods of those segments
where  pitch  analysis  is  appropriate,  and  computes   a  list  of
parameters  for each  segment.   A classification  program  assigns a
phoneme-group  label  (vowel-like  segment,  fricative-like  segment,
etc.)  to  each  segment, determines  whether  a  segment  should  be
classified as  a phoneme or whether it  represents a phoneme boundary
between two  phonemes,  and then  assigns  a  phoneme label  to  each
segment that is  not rejected as being a phoneme  boundary.  About 30
utterances  of one  to two seconds  duration were  analyzed using the
above programs on an interconnnected IBM 7090-PDP-1  system.  Correct
identification  of many vowel  and consonantal phonemes  was achieved
for a single speaker.   The time for  analysis of each utterance  was
about 40 times real time.  The results  were encouraging and point to
a new direction in speech research.

*AIM-44,,,
James Painter,
"Semantic Correctness of a Compiler for an Algol-like Language"
Thesis: Ph.D. in Computer Science,
130 pages, revised March 1967.

This is  a semantic  proof of  the correctness  of a  compiler.   The
abstract  syntax and semantic  definition are given  for the language
Mickey,  an extension  of  Micro-algol.    The  abstract  syntax  and
semantics are  given for  a hypothetical  one-register single-address
computer  with 14 operations.   A compiler,  using recursive descent,
is defined.   Formal definitions are also  given for state vector,  a
and  c  functions,  and  correctness  of  a compiler.    Using  these
definitions, the compiler is proven correct.

AIM-45,,,
Donald Kaplan,
"Some Completeness Results in the Mathematical Theory of Computation"
22 pages, October 1966.

A  formal theory  is described  which  incorporates the  `assignment'
function  a(i, k, psi)  and the `contents'  function c(i,  psi).  The
axioms of the theory are shown to comprise a complete  and consistent
set.

*AIM-46, CS-50, PB176761,
Staffan Persson,
"Some Sequence Extrapolating Programs: a Study of Representation and
 Modeling in Inquiring Systems"
Thesis: Ph.D. in Computer Science,
176 pages, September 1966.

The purpose  of  this thesis  is to  investigate  the feasibility  of
designing   mechanized   inquiring-systems   for   finding   suitable
representations of problems, i.e., to perform the `creative'  task of
finding analogies.   Because  at present a  general solution  to this
problem  does  not  seem  to  be  within  reach,  the feasibility  of
mechanizing a  particular representational  inquirer is  chosen as  a
reasonable  first   step  towards an  increased understanding  of the
general problem.    It  is  indicated  that  by  actually  designing,
programming and running a representational inquirer  as a program for
a  digital computer, a severe  test of its  consistency and potential
for future extensions can be performed.

*AIM-47,,,
Bruce Buchanan,
"Logics of Scientific Discovery"
Thesis: Ph.D. in Philosophy U.C. Berkeley,
210 pages, December 1966.

The  concept   of  a  logic   of  discovery   is  discussed  from   a
philosophical point  of view.  Early chapters  discuss the concept of
discovery itself,   some  arguments have  been  advanced against  the
logics of discovery,  notably by N. R.   Hanson, and S.  E.  Toulmin.
While  a  logic  of  discovery  is  generally  understood  to  be  an
algorithm  for formulating  hypotheses,    other concepts  have  been
suggested.   Chapters V  and VI explore  two of  these: (A) a  set of
criteria by which a hypothesis could be judged reasonable, and (B)  a
set  of  rational   (but  not  necessarily  effective)   methods  for
formulating hypotheses.
AIM-48,,,
Donald M. Kaplan,
"Correctness of a Compiler for Algol-like Programs"
46 pages, July 1967.

A compiling  algorithm  is given  which maps  a  class of  Algol-like
programs into  a class of machine language  programs.  The semantics,
i. e.,  the effect  of execution,  of each  class  is specified,  and
recursion  induction   used  to  prove  that   program  semantics  is
preserved under the mapping defined by the compiling algorithm.

AIM-49,,,
Georgia Sutherland,
"DENDRAL -- a Computer Program for Generating and Filtering Chemical
 Structures"
34 pages, February 1967.

A  computer program  has  been written  which  can generate  all  the
structural  isomers   of  a  chemical  composition.    The  generated
structures are  inspected  for forbidden  substructures in  order  to
eliminate  structures  which  are   chemically  impossible  from  the
output.     In   addition,  the   program  contains   heuristics  for
determining   the   most   plausible   structures,    for   utilizing
supplementary  data, and  for interrogating  the on-line  user  as to
desired options and  procedures.  The  program incorporates a  memory
so that past experiences are utilized in later work.

AIM-50,,,
Anthony C. Hearn,
"Reduce Users' Manual"
53 pages, February 1967.

REDUCE is  a program designed  for general algebraic  computations of
interest to physicists and engineers.  Its capabilities include:
.bs
1) expansion and ordering  of rational functions of polynomials,

2) symbolic differentiation,

3) substitutions in a wide variety of forms,

4) reduction  of quotients of  polynomials by cancellation  of common
   factors,

5) calculation of symbolic determinants,

6) calculations of interest to high  energy physicists including spin
   1/2 and spin 1 algebra.  
.end

The program  is written completely in  the language LISP  1.5 and may
therefore be run with little modification on any computer  possessing
a LISP 1.5 compiler or interpreter.

AIM-51,,,
Lester D. Earnest,
"Choosing an eye for a Computer"
154 pages, April 1967.

In order  for a computer  to operate  efficiently in an  unstructured
environment,  it  must have one or more manipulators (e. g., arms and
hands) and a spatial sensor  analogous to the human eye.  Alternative
sensor  systems are  compared here  in their  performance on  certain
simple  tasks.  Techniques for determining  color, texture, and depth
of  surface  elements are  examined.    Sensing  elements  considered
include  the  photomultiplier,    image  dissector,  image  orthicon,
vidicon,  and SEC camera  tube.  Performance measures strongly  favor
a new (and undemonstrated)  configuration that may be termed  a laser
jumping spot system.

AIM-52,,,
Arthur L. Samuel,
"Some Studies in Machine Learning Using the Game of Checkers II -
 Recent Progress"
48 pages, June 1967.

.bi
A  new  signature  table technique  is  described  together  with  an
improved  book  learning  procedure  which  is  thought  to  be  much
superior to the linear polynomial method described earlier.  Full use
is made  of the so called  <alpha-beta> pruning and several  forms of
forward  pruning  to restrict  the  spread of  the move  tree  and to
permit the  program to look  ahead to  a much  greater depth than  it
otherwise could  do.  While still unable  to outplay checker masters,
the programs's playing ability  has been greatly  improved.  Some  of
these newer techniques  should be applicable to problems  of economic
importance.
.end

AIM-53,,,
William Weiher,
"The PDP-6 Proof Checker"
47 pages, June 1967.

A  descrription  is  given  for  the  use  of  a  proof  checker  for
propositional calculus.   An example of its use as  well as the M and
S expressions for the proof checker are also included.

AIM-54,,,
Joshua Lederberg, Edward A. Feigenbaum,
"Mechanization of Inductive Inference in Organic Chemistry"
29 pages, August 1967.

A computer program for formulating hypotheses in  the area of organic
chemistry is  described from two standpoints: artificial intelligence
and  organic  chemistry.     The   Dendral  Algorithm  for   uniquely
representing   and   ordering   chemical   structures   defines   the
hypothesis-space;   but  heuristic   search  through   the  space  is
necessary  because  of  its  size.    Both  the   algorithm  and  the
heuristics  are described  explicitly  but without  reference  to the
LISP code  in which  these  mechanisms are  programmed.   Within  the
program some  use has been  made of man-machine  interaction, pattern
recognition,  learning,   and  tree-pruning  heuristics  as  well  as
chemical heuristics which  allow the program  to focus its  attention
on a subproblem to rank the  hypotheses in order of plausibility. The
current  performance  of  the program  is  illustrated  with selected
examples of actual output showing both its  algorithmic and heuristic
aspects.     In  addition   some  of   the  more   important  planned
modifications are discussed.

AIM-55,,,
Jerome Feldman,
"First Thoughts of Grammatical Inference"
18 pages, August 1967.

A number  of issues relating  to the problem  of inferring  a grammar
are  disscussed.  A  strategy for grammatical  inference is presented
and its weaknesses and possible improvements are discussed.   This is
a  working paper  and should  not be  reproduced, quoted  or believed
without the author's permission.     .

AIM-56,,,
William Wichman,
"Use of Optical Feedback in the Computer Control of an Arm"
Thesis: Eng. in Electrical Engineering,
69 pages, August 1967.

This paper reports  an experimental investigation of  the application
of  visual feedback  to  a simple  computer-controller block-stacking
task.    The  system  uses  a  vidicon  camera  to  examine  a  table
containing two  cubical blocks, generating a  data structure which is
analyzed to determine  the position of  one block.   An electric  arm
picks up  the block  and removes  it from the  scene, then  after the
program  locates the  second block,  places the  first on top  of the
second.  Finally, the alignment of the stack is  improved by analysis
of the relative position error  as seen by the camera.  Positions are
determined  throughout   by  perspective   transformation  of   edges
detected from  a single  viewpoint,   using a  support hypothesis  to
supply  sufficient information on  depth.  The  Appendices document a
portion of the hardware used in the project.

AIM-57,,,
Anthony C. Hearn,
"REDUCE, a User-oriented Interactive System for Algebraic Simplification"
69 pages, October 1967.

This paper describes  in outline the  structure and use of  REDUCE, a
program  designed for large-scale algebraic  computations of interest
to  applied   mathematicians,   physicists,   and   engineers.   The
capabilities of the system include:
.bs
1)  expansion,  ordering  and  reduction  of  rational  functions  of
    polynomials,

2)  symbol  differentiation,

3)  substitutions for variables  and expressions  appearing in  other
    expressions,

4)  simplification of  symbolic determinants and matrix  expressions,

5)  tensor and  non-commutative  algebraic calculations  of  interest
    to high energy physicists.
.end

In   addition   to   the   operations   of   addition,   subtraction,
multiplication,    division,   numerical   exponentiation   numerical
exponentiation and differentiation,  it is possible  for the user  to
add  new  operators  and   define  rules  for  their  simplification.
Derivations  of these operators  may also  may also be  defined.

The program is  written complete in the  language of LISP 1.5  and is
organized so as  to minimize the effort required in transferring from
one LISP system to another.

Some particular  problems  which have  arisen in  using  REDUCE in  a
time-sharing environment are also discussed.

AIM-58,,,
Monte D. Callero,
"An Adaptive Command and Control System Utilizing Heuristic Learning
 Processes"
Thesis: Ph.D. in Operations Research,
161 pages, December 1967.

The  objectives of  the  research reported  here  are to  develop  an
automated  decision  process  for  real  time  allocation of  defense
missiles to  attacking  ballistic  missiles  in general  war  and  to
demonstrate the effectiveness of  applying heuristic learning to seek
optimality  in the process.  The approach  is to model and simulate a
missile  defense  environment  and  generate  a   decision  procedure
featuring  a   self-modifying,  heuristic  decision   function  which
improves its performance with experience.   The goal of the  decision
process that chooses between the feasible  allocations is to minimize
the  total  effect of  the  attack, measured  in  cumulative  loss of
target value.   The  goal is  pursued indirectly  by considering  the
more general  problem of  maintaining a  strong defense  posture, the
ability  of  the defense  system  to  protect the  targets  from both
current  and future loss.

.bi
Using simulation  and  analysis,  a  set of  calculable <features> are
determined  which effectively  reflect the marginal  deterioration of
defense posture for each allocation  in a time interval.  A <decision
function>,   a linear polynomial  of the  features,  is  evaluated for
each  feasible  allocation  and the  allocation  having  the smallest
value is selected.   A heuristic learning process is  incorporated in
the model  to evaluate the  performancee of the  decision process and
adjust  the  decision  function  coefficients  to  encourage  correct
comparison of alternative allocations.   Simulated attacks presenting
typical   defense  situations   were  cycled  against   the  decision
procedure with  the result  that the  decision function  coefficients
converged under the learning process  and the decision process become
increasingly effective.
.end

*AIM-59,,,
Donald M. Kaplan,
"A Formal Theory Concerning the Equivalence of Algorithms"
20 pages, May 1968.

Axioms  and rules  of  inference  are  given for  the  derivation  of
equivalence for  algorithms.  The theory is  shown to be complete for
certain subclasses  of algorithms,  and several  applications of  the
theory are illustrated.   This paper was originally  presented at the
Mathematical  Theory of Computation Conference, IBM Yorktown Heights,
November 27-30, 1967.

AIM-60, CS-101, AD672923,
Donald M. Kaplan,
"The Formal Theoretic Analysis of Strong Equivalence for Elemental
 Programs"
Thesis: Ph.D. in Computer Science,
263 pages, June 1968.

The syntax  and semantics is  given for  elemental programs, and  the
strong equivalence of  these simple ALGOL-like flowcharts is shown to
be  undecidable.    A  formal  theory  is  introduced   for  deriving
statements  of  strong  equivalence,  and the  completeness  of  this
theory  is obtained for  various sub-cases.   Several applications of
the theory are discussed.  Using a  regular expression representation
for  elemental   programs  and  an  unothodox   semantics  for  these
expressions, several  strong  equivalence  detecting  procedures  are
developed.  This work  was completed in essentially its  present form
March, 1968.

*AIM-61,,,
Takayasu Ito,
"Notes on Theory of Computation and Pattern Recognition"
144 pages, May 1968.

This  is a  collection of  some  of the  author's  raw working  notes
during   the   period   December 1965 - October   1967  besides   the
introduction.   They have  been privately  or internally  distributed
for  some  time.   Portions  of  this  work  have been  accepted  for
publication;  others are being developed  for submission to journals.
Some aspects  and ideas  have been  referred to  and used,  sometimes
without  explicit  references,  and  others  are developed  by  other
researchers and the author.   Hence we have  decided to publish  this
material as a Computer Science Technical  Report, although the author
is  planning to submit  all of these  works to  some journals, adding
several  new  results  (not  mentioned  in  this  report),  improving
notations, definitions  and style of  presentation in some  parts and
reformulating   completely  in   other  parts.

AIM-62,,,
Bruce Buchanan, Georgia Sutherland,
"Heuristic Dendral: a Program for Generating Explanatory Hypotheses in
 Organic Chemistry"
76 pages, July 1968.

A computer  program has been  written which can  formulate hypotheses
from a  given set of scientific  data.  The data  consist of the mass
spectrum and the empirical  formula of an organic chemical  compound.
The  hypotheses which  were  produced  describe molecular  structures
which  are plausible  explanations of the  data.   The hypotheses are
generated systematically  within  the  program's theory  of  chemical
stability  and within limiting  constraints  which are  inferred from
the data  by  heuristic  rules.    The  program  excludes  hypotheses
inconsistent  with  the  data and  lists  its  candidate  explanatory
hypotheses in order of decreasing plausibility.  The computer program
is heuristic in that it searches for plausible hypotheses in  a small
subset of  the total  hypothesis space  according to  heuristic rules
learned from chemists.

AIM-63,,,
Donald M. Kaplan,
"Regular Expressions and the Equivalence of Programs"
42 pages, July 1968.

The strong  equivalence  of ALGOL-like  programs is,  in general,  an
undecidable  property.  Several mechanical  procedures  are discussed
which  nevertheless   are   useful  in   the  detection   of   strong
equivalence.     These  methods   depend  on  a   regular  expression
representation   of  programs.  An  unorthodox  semantics  for  these
expressions is introduced  which appreciably adds  to the ability  to
detect strong  equivalence.  Several other methods  of extending this
ability are also discussed.

*AIM-64,,,
Zohar Manna,
"Formalization of Properties of Programs"
18 pages, July 1968.

Given a program, an  algorithm will be described for  constructing an
expression,  such that  the program  is  valid (i.e.,  terminates and
yields  the  right  answer)  if   and  only  if  the  expression   is
inconsistent.    Similar  result   for  the  equivalence  problem  of
programs is  given.  These results suggest a new approach for proving
the validity and equivalence of programs.

AIM-65, CS-106, AD673971,
Barbara J. Huberman,
"A Program to Play Chess end Games"
Thesis: Ph.D. in Computer Science,
168 pages, August 1968.

A program to  play chess end games is  described.  The model  used in
the  program  is very  close to  the  model assumed  in  chess books.
Embedded in the model  are two predicates,   BETTER and WORSE,  which
contain  the heuristics  of play,  different for  each end  game. The
definitions   of  BETTER  and  WORSE   were  obtained  by  programmer
translation from the chess books.

The program model  is shown to be a  good one for chess and  games by
the success achieved  for three end games.  Also the model enables us
to prove  that the  program  can reach  checkmate from  any  starting
position.    Insights about  translation  from  book problem  solving
methods  into  computer program  heuristics  are discussed;  they are
obtained by  comparing the  chess  book methods  with definitions  of
BETTER and  WORSE,  and by considering  the difficulty encountered by
the programmer when doing the translation.

*AIM-66,,,
Jerome A. Feldman, Paul D. Rovner,
"An Algol-based Associative Language"
31 pages, August 1968.

.bi
A  high-level  programming  language  for  large  complex  relational
structures  has  been  designed  and  implemented.    The  underlying
relational data structure  has been  implemented using a  hash-coding
technique.  The discussion includes  a comparison with other work and
examples  of applications of the  language.  A  version of this paper
will appear in the <Communications of the ACM>.
.end

*AIM-67,,AD680487,
Edward A. Feigenbaum,
"Artificial Intelligence: Themes in the Second Decade"
39 pages, August 1968.

In this survey  of Artificial Intelligence research,  the substantive
focus   is  heuristic  programming,  problem   solving,  and  closely
associated  learning models.    The  focus  in  time  is  the  period
1963-1968.    Brief  tours  are   made  over  a  variety  of  topics:
generality,   integrated  robots,  game   playing,  theorem  proving,
semantic information processing, etc.

One  program,    which  employs  the  heuristic  search  paradigm  to
generate  explanatory hypotheses in  the analysis of  mass spectra of
organic molecules,   is described  in some  detail.   The problem  of
representation  for problem  solving systems  is discussed.   Various
centers  of excellence  in the Artificial  Intelligence research area
are mentioned.  A bibliography of 76 references is given.

AIM-68,,,
Zohar Manna, Amir Pnueli,
"The Validity Problem of the 91-function"
20 pages, August 1968.

Several  methods  for  proving  the  weak   and  strong  validity  of
algorithms  are  presented.

For   proving  the   weak  validity   (i.e.,   correctness)  we   use
satisfiability  methods,  while proving  the  strong  validity (i.e.,
termination and correctness) we use unsatisfiability methods.

Two types of algorithms are discussed: recursively  defined functions
and programs.

Among the  methods we  include known  methods due  to Floyd,   Manna,
and  McCarthy.  All the  methods will be  introduced quite informally
by means of an example (the 91-function).

*AIM-69,, AD677588,
John McCarthy, Edward Feigenbaum, Arthur Samuel,
"Project Technical Report"
90 pages, September 1968.

Recent  work   of   Stanford  Artificial   Intelligence  Project   is
summarized in several areas:
.bc
     Scientific Hypothesis Formation
     Symbolic Computation
     Hand-Eye Systems
     Computer Recognition of Speech
     Board Games
     Other Projects
.end

AIM-70,, AD680072,
Anthony C. Hearn,
"The Problem of Substitution"
14 pages, December 1968.

One  of  the  most significant  features  of  programs  designed  for
non-numeric   calculation   is   that   the   size   of   expressions
manipulated,  and  hence the  amount  of  storage necessary,  changes
continually  during the execution of the  program.  It is, therefore,
usually not possible for the  user to know ahead of time  whether the
calculation will  in fact fail because of  lack of available computer
memory.    The  key  to   keeping  both  the  size  of   intermediate
expressions and  output under  control often  lies in  the manner  in
which  substitutions for  variables and  expressions declared  by the
programmer are  implemented by  the system.   In  this paper  various
methods which have  been developed to perform  these substitutions in
the  author's own system  REDUCE are discussed.   A brief description
of the REDUCE system is also given.

AIM-71,, AD677520,
Pierre Vicens,
"Preprocessing for Speech Analysis"
33 pages, October 1968.

This paper  describes a procedure,  and its  hardware implementation,
for the extraction  of significant parameters of speech.  The process
involves division of  the speech  spectrum into convenient  frequency
bands, and  calculation of amplitude and  zero-crossing parameters in
each  of these bands every 10 ms.   In the software implementation, a
smooth function divides the speech spectrum into  two frequency bands
(above  and below  1000  Hz).   In the  hardware  implementation, the
spectrum is divided into three bands using bandpass filters  (150-900
Hz,  900-2200  Hz,  2200-5000  Hz).    Details   of  the  design  and
implementation of the hardware device are given.

*AIM-72, CS-116, AD680036,
Donald L. Pieper,
"The Kinematics of Manipulators under Computer Control"
Thesis: Ph.D. in Mechanical Engineering,
157 pages, October 1968.

The kinematics  of manipulators are  studied.   A model is  presented
which  allows  for the  systematic  description of  new  and existing
manipulators.

Six degree-of-freedom manipulators are studied.  Several solutions to
the  problem of  finding the manipulator  configuration leading  to a
specified position and orientation are presented.  Numerical  as well
as  explicit solutions  are  given.   The  problem  of positioning  a
multi-link digital arm is also discussed.

Given the solution to  the position problem, as  a set of  heuristics
is developed for  moving a six degree-of-freedom manipulator  from an
initial  position  to a  final  position through  a  space containing
obstacles.  This results  in a computer program  shown to be able  to
direct a manipulator around obstacles.

*AIM-73,, AD678878,
John McCarthy, Patrick Hayes,
"Some Philosophical Problems From the Standpoint of Artificial
 Intelligence"
51 pages, November 1968.

A computer program capable of acting intelligently  in the world must
have  a general  representation of  the world in  terms of  which its
inputs  are  interpreted.     Designing   such  a  program   requires
commitments about  what knowledge is  and how  it is obtained.   Thus
some  of  the  major  traditional  problems  of  philosophy arise  in
artificial intelligence.

More specifically,  we want  a computer program that decides  what to
do by  inferring in  a formal language  that a certain  strategy will
achieve its assigned  goal.   This requires  formalizing concepts  of
causality,  ability,    and  knowledge.   Such  formalisms  are  also
considered in philosophical logic.

.oi
The  first part  of the  paper begins with  a philosophical  point of
view that seems to  arise naturally once  we take seriously the  idea
of actually making  an intelligent machine.  We go  on to the notions
of  metaphysically and epistemologically  adequate representations of
the world and  then to an explanation  of <can, causes>, and <knows>, in
terms of  a representation  of the world  by a system  of interacting
automata.  A  proposed resolution  of the  problem of  freewill in  a
deterministic universe  and of  counterfactual conditional  sentences
is presented.

The second part is  mainly concerned with formalisms within  which it
can  be  proved that  a strategy  will  achieve a  goal.  Concepts of
situation, fluent,  future operator,  action,  strategy, result of  a
strategy  and  knowledge  are  formalized.   A  method  is  given  of
constructing  a sentence of first  order logic which  will be true in
all models of certain axioms  if and only is a certain  strategy will
achieve a certain goal.

The  formalism of  this paper  represents an  advance  over (McCarthy
1963) and (Green 1968)  in that it permits  proof of the  correctness
of strategies  that  contain loops  and strategies  that involve  the
acquisition of knowledge, and it is also somewhat more concise.

The third part  discusses open problems in extending the formalism of
Part II.

.oi
The fourth  part  is  a review  of  work in  philosophical  logic  in
relation  to  problems of  Articial  Intelligence  and discussion  of
previous efforts  to program <general intelligence> from the point of
view of this paper.  This  paper is based on a talk given to  the 4th
Machine Intelligence Workshop  held at Edinburgh, August 12-21, 1968,
and  is  a  preprint  of  a   paper  to  be  published  in   <Machine
Intelligence 4> (Edinburgh University Press, 1969).

*AIM-74, CS-118, AD681027,
Donald Waterman,
"Machine Learning of Heuristics"
Thesis: Ph.D. in Computer Science,
? pages, December 1968.

The    research   reported   here   is    concerned   with   devising
machine-learning techniques which  can be applied  to the problem  of
automating the learning heuristics.

*AIM-75,,,
Roger C. Schank,
"A Notion of Linguistic Concept: a Prelude to Mechanical Translation"
21 pages, December 1968.

The conceptual  dependency framework  has been  used as an  automatic
parser  for natural  language.   Since the parser  gives as  output a
conceptual network  capable of  expressing meaning  in  language-free
terms,  it is  possible to  regard  this as  an interlingua.   If  an
interlingua is  actually available how might this interlingua be used
in translation?    The primary  problem that  one  encounters is  the
definition of just what these  concepts in the network are. A concept
is defined as an abstraction in  terms of percepts and the  frequency
of  connection  of  other concepts.    This  definition  is  used  to
facilitate the understanding  of some of the problems in paraphrasing
and translation.   The  motivation for  this  abstract definition  of
linguistic concept is discussed in the context of its proposed use.

DESCRIPTORS: computational  linguistics, concepts  research, computer
understanding.

*AIM-76,,,
Roger C. Schank,
"A Conceptual Parser for Natural Language"
22 pages, December 1968.

This  paper  describes  an  operable  automatic  parser  for  natural
language.   The parser is not concerned  with producing the syntactic
structure of an input sentence.  Instead, it is a  conceptual parser,
concerned with determining  the underlying meaning of  the input. The
output  of  the  parser  is a  network  of  concepts  explicating the
conceptual relationships in a  piece of discourse.  The  structure of
this  network  is   language-free;  thus,    sentences  in  different
languages or paraphrases  within the  same language  will parse  into
the same network.  The theory behind  this representation is outlined
in this paper and the parsing algorithm is explained in some detail.

DESCRIPTORS:   computational   linguistics,   concepts,    linguistic
research, computer understanding.

AIM-77,,,
Joseph D. Becker,
"The Modeling of Simple Analogic and Inductive Processes in a Semantic
 Memory System"
21 pages, January 1969.

In  this  paper  we  present  a general data structure for a semantic
memory, which is  distinguished  in  that  a  notion  of  consequence
(temporal,    causal,    logical,   or   behavioral,   depending   on
interpretation) is a primitive of the data representation.  The  same
item of a data may at one time serve as a logical implication, and at
another time as a `pattern/action' rule for behavior.

We  give  a  definition  of  `analogy'  between  items  of   semantic
information.   Using  the  notions  of  consequence  and  analogy, we
construct an inductive process in which general laws  are  formulated
and  verified  on  the basis of observations of individual cases.  We
illustrate in detail the attainment of the  rule  `Firemen  wear  red
suspenders'  by  this  process.

Finally, we discuss  the relationship between analogy  and induction,
and   their   use   in   modeling   aspects   of   `perception'   and
`understanding'.

AIM-78,,,
D. Raj. Reddy,
"On the use of Environmental, Syntactic and Probalistic Constraints in
 Vision and Speech"
23 pages, January 1969.

In this paper we consider both vision and speech in the hope  that  a
unified  treatment,  illustrating  the  similarities, would lead to a
better appreciation of the problems, and possibly programs which  use
the  same  superstructure.   We postulate a general perceptual system
and illustrate how various existing systems either  avoid  or  ignore
some  of  the difficult problems that must be considered by a general
perceptual system.  The purpose of this paper is to point out some of
the  unsolved  problems,  and to suggest some heuristics that reflect
environmental, syntactic, and  probabilistic  constraints  useful  in
visual  and  speech  perception by machine.  To make effective use of
these  heuristics,  a  program  must  provide  for
.bs
1. An external  representation of heuristics for ease  of man-machine
   communication

2. An  internal  representation of  heuristics for  effective use  by
   machine

3. A mechanism  for the selection  of appropriate heuristics  for use
   in a given situation.
.end

Machine perception of  vision and speech,   thus, provides  a problem
domain  for  testing the  adequacy  of the  models  of representation
(McCarthy and Hayes),  planning heuristic selection (Minsky,   Newell
and Simon), and  generalization learning (Samuel); a  domain in which
(perceptual)  tasks  are  performed  by  people  easily  and  without
effort.

AIM-79,, AD685611,
D. Raj. Reddy, Richard B. Neely,
"Contextual Analysis of Phonemes of English"
71 pages, January 1969.

It is now well known that the acoustic characteristics of  a  Phoneme
depend  on  both  the  preceding  and following phonemes.  This paper
provides some needed contextual and probabilistic data about  trigram
phonemic  sequences of spoken English.  Since there are approximately
40↑3 such sequences, one  must  discover  and  study  only  the  more
commonly occurring sequences.  To this purpose, three types of tables
are presented, viz.,
.bs
a.  Commonly occurring trigram sequences of  the form /abc/ for every
   phoneme /b/.

b.   Commonly occurring sequences  /abc/ for  every pair of  phonemes
   /a/ and /c/.

c.  Commonly occurring word boundary sequences  of the form /-ab/ and
   /ab-/ where /-/ represents the silence phoneme.
.end

Entries  of   the  above  tables   contain  examples  of   usage  and
probabilities of occurrence for each such sequence.

*AIM-80,, AD685612,
Georgia Sutherland,
"Heuristic Dendral: a Family of LISP Programs"
46 pages, March 1969.

The  Heuristic  Dendral program for generating explanatory hypotheses
in  organic  chemistry  is  described  as  an  application   of   the
programming   language   LISP.    The   description   emphasizes  the
non-chemical aspects of the program,  particularly  the  `topologist'
which generates all tree graphs of a collection of nodes.

*AIM-81,, AD685613,
David Luckham,
"Refinement Theorems in Resolution Theory"
31 pages, March 1969.

The  paper  discusses  some  basic  refinements  of  the   Resolution
Principle  which  are intended to improve the speed and efficiency of
theorem-proving programs based on this  rule  of  inference.   It  is
proved  thxt two of the refinements preserve the logical completeness
of the proof procedure when used separately, but  not  when  used  in
conjunction.  The  results  of  some preliminary experiments with the
refinements are given.

Presented at the  IRIA Symposium on Automatic  Deduction, Versailles,
France, December 16-21, 1968.

*AIM-82,, AD685614,
Zohar Manna, Amir Pneuli,
"Formalization of Properties of Recursively Defined Functions"
26 pages, March 1969.

This  paper  is  concerned  with   the   relationship   between   the
convergence,  correctness  and  equivalence  of  recursively  defined
functions and the satisfiability  (or  unsatisfiability)  of  certain
first-order formulas.

*AIM-83, CS-130,,
Roger C. Schank,
"A Conceptual Representation for Computer-oriented Semantics"
Thesis: Ph.D. in Linguistics U. of Texas,
201 pages, March 1969.

Machines that may be said to function intelligently must be  able  to
understand  questions  posed  in  natural  language.   Since  natural
language may be assumed to have an underlying  conceptual  structure,
it  is  desirable  to  have the machine structure its own experience,
both linguistic and nonlinguistic, in a manner concomitant  with  the
human  method for doing so.  Some previous attempts at organizing the
machine's    data    base    conceptually    are    discussed.      A
conceptually-oriented dependency grammar is posited as an interlingua
that may be used as an  abstract  representation  of  the  underlying
conceptual  structure.   The  conceptual dependencies are utilized as
the  highest  level  in  a  stratified   system   that   incorporates
language-specific  realization  rules  to map from concepts and their
relations, into sentences.  In order to generate coherent  sentences,
a  conceptual  semantics  is  posited that limits possible conceptual
dependencies to statements about the system's knowledge of  the  real
world.   This is done by the creation of semantic files that serve to
spell out  the  defining  characteristics  of  a  given  concept  and
enumerate  the possibilities for relations with other concepts within
the range of conceptual experience. The semantic files  are  created,
in  part,  from  a  hierarchical organization of semantic categories.
The semantic category is part of the definition of a concept and  the
information  at  the  nodes  dominating  the semantic category in the
hierarchical tree may be used to fill in the semantic  file.   It  is
possible to reverse the realization rules to operate on sentences and
produce a conceptual parse.  All potential parses  are  checked  with
the conceptual semantics in order to eliminate semantic and syntactic
ambiguities.  The system has been programmed; coherent sentences have
been  generated  and  the  parser  is operable.  The entire system is
posited as a viable linguistic theory.

*AIM-84,, AD691791,
David Canfield Smith,
"MLISP Users' Manual"
57 pages, January 1969.

MLISP  is  a  LISP  pre-processor designed to facilitate the writing,
use, and understanding of LISP progams.  This is accomplished through
parentheses  reduction,  comments, introduction of a more visual flow
of control with block structure and mnemonic key words, and  language
redundancy.  In  addition,  some  `meta-constructs' are introduced to
increase the power of the language.

*AIM-85, CS-127, AD687720,
Pierre Vicens,
"Aspects of Speech Recognition by Computer"
Thesis: Ph.D. in Computer Science,
210 pages, April 1969.

This  thesis describes techniques and methodology which are useful in
achieving close to real-time recognition of speech by  computer.   To
analyze  connected  speech  utterances, any speech recognition system
must perform the following  processes:  preprocessing,  segmentation,
segment   classification,   recognition   of  words,  recognition  of
sentences.   We  present  implemented  solutions  to  each  of  these
problems which achieved accurate recognition in all the trial cases.

*AIM-86,, AD691788,
Patrick J. Hayes,
"A Machine-oriented Formulation of the Extended Functional Calculus"
44 pages, June 1969.

The  Extended  Functional  Calculus  (EFC),  a three-valued predicate
calculus intended as a language in which to reason about the  results
of  computations, is described in some detail.  A formal semantics is
given.  A machine-oriented (axiomless) inference system  for  EFC  is
then  described  and  its  completeness  relative to the semantics is
proved by the method of Semantic Trees. Finally some remarks are made
on efficiency.

*AIM-87,, AD691789,
John McCarthy, A.I. Project Staff,
"Project Technical Report"
98 pages, June 1969.

Plans  and  accomplishments  of  the Stanford Artificial Intelligence
Project are reviewed in several areas including: theory (epistemology
and  mathematical  theory  of  computation),  visual  perception  and
control  (Hand-eye  and  Cart),  speech  recognition   by   computer,
heuristics  in  machine  learning  and automatic deduction, models of
cognitive  processes  (Heuristic  DENDRAL),  Language  Research,  and
Higher Mental Functions. This is an excerpt of a proposal to ARPA.

*AIM-88,, AD691790,
Roger C. Schank,
"Linguistics from a Conceptual Viewpoint (Aspects of Aspects of a
 Theory of Syntax)"
22 pages, April 1969.

Some  of  the  assertions  made  by  Chomsky in Aspects of Syntax are
considered.  In particular, the notion of  a  `competence'  model  in
linguistics is criticized. Formal postulates for a conceputally-based
linguistic theory are presented.

AIM-89, CS-125, AD692390,
Jerome A. Feldman, J. Gips, J. J. Horning, and S. Reder,
"Grammatical Complexity and Inference"
100 pages, June 1969.

The problem of inferring a grammar for a set  of  symbol  strings  is
considered  and  a  number  of  new  decidability  results  obtained.
Several notions of grammatical complexity and  their  properties  are
studied. The question of learning the least complex grammar for a set
of strings is investigated leading  to  a  variety  of  positive  and
negative  results.  This work is part of a continuing effort to study
the  problems  of  representation  and  generalization  through   the
grammatical inference question.

*AIM-90,, AD691799,
Anthony C. Hearn,
"Standard LISP"
33 pages, May 1969.

A uniform subset of LISP 1.5 capable of assembly under a  wide  range
of existing compilers and interpreters is described.

AIM-91,,,
J. A. Campbell and Anthony C. Hearn,
"Symbolic Analysis of Feynman Diagrams by Computer"
73 pages, August 1969.

We describe  a  system of  programs in  the language  LISP 1.5  which
handles  all  stages  of calculation  from  the  specification of  an
elementary-particle process in terms of a Hamiltonian  of interaction
or Feynman  diagrams to the derivation  of an absolute square  of the
matrix  element for  the process.   Examples of  significant parts of
the programs are presented in  the text, while a detailed  listing of
this material  is contained in two Appendices  which are available on
request from the authors.

*AIM-92,,,
Victor D. Scheinman,
"Design of a Computer Controlled Manipulator"
Thesis: Eng. in Mechanical Engineering,
53 pages, June 1969.

This  thesis  covers  the  preliminary  system  studies,  the  design
process, and the design details associated with the design of  a  new
computer   controlled   manipulator   for   the  Stanford  Artificial
Intelligence  Project.   A  systems  study  of  various   manipulator
configurations,  force  sensing  methods, and suitable components and
hardware was first performed. Based on this study, a  general  design
concept  was  formulated.  This  concept  was  then  developed into a
detailed manipulator design,  having  six  degrees  of  freedom,  all
electric  motor  powered.   The  manipulator  has  exceptionally high
position accuracy, comparatively  fast  feedback  servo  performance,
and approximately  human arm reach and motion properties.  Supporting
some of the design details and selections are several examples of the
design calculation procedure employed.

AIM-93.1,, AD693106,
Jerome Feldman,
"Some Decidability Results on Grammatical Inference and Complexity"
31 pages, August 1969, revised May 1970.

The  problem  of  grammatical inference is considered and a number of
positive answers to decidability questions obtained.  Conditions  are
prescribed  under  which  it  is  possible  for  a machine to infer a
grammar (or the best grammar) for even the general rewriting systems.

This  revision was  motivated  by  the  discovery that  our  original
definition of approachability  was too weak and could be satisfied by
trivial  inference devices.    Definition  1.2  and  the  surrounding
material discuss this situation.

The  theorems in  Section  2  have been  slightly  reordered and  new
proofs given.   The explicit use of a bounding function gives rise to
an  important new  result,  Corollary  2.4.   Section  3  is  changed
primarily  in   the  more  detailed  discussion   of  mixed  strategy
machines.

AIM-94,, AD692391,
Kenneth Mark Colby, Lawrence Tesler, Horace Enea,
"Experiments With a Search Algorithm on the Data Base of a Human
 Belief Structure"
28 pages, August 1969.

Problems of collecting data regarding human beliefs  are  considered.
Representation  of  this  data  in a computer model designed to judge
credibility involved paraphrasings from  natural  language  into  the
symbolic  expressions of the programming language MLISP.  Experiments
in processing this  data  with  a  particular  search  algorithm  are
described, discussed and criticized.

*AIM-95,, AD694971,
Zohar Manna,
"The Correctness of Non-deterministic Programs"
44 pages, August 1969.

In this paper we formalize properties of  non-deterministic  programs
by   means   of  the  satisfiability  and  validity  of  formulas  in
first-order logic.  Our main purpose is to emphasize the wide variety
of possible applications of the results.

*AIM-96, CS-138, AD696394,
Claude Cordell Green,
"The Application of Theorem Proving to Question-answering Systems"
Thesis: Ph.D. in Electrical Engineering,
166 pages, August 1969.

This paper shows how a question-answering system can use  first-order
logic  as its language and an automatic theorem prover based upon the
resolution inference  principle  as  its  deductive  mechanism.   The
resolution  proof  procedure  is  extended  to  a  constructive proof
procedure.  An answer construction algorithm  is  given  whereby  the
system is able not only to produce yes or no answers but also to find
or construct an object satisfying a specified condition.   A  working
computer  program,  QA3,  based  on  these  ideas, is described.  The
performance  of  the  program,  illustrated  by  extended   examples,
compares  favorably  with several other  question-answering programs.

Methods are presented for solving state transformation  problems.  In
addition   to   question-answering,  the  program  can  do  automatic
programming  (simple  program   writing,   program   verifying,   and
debugging),  control  and problem solving for a simple robot, pattern
recognition (scene description), and puzzles.

AIM-97,, AD694972,
Kenneth Mark Colby, David Canfield Smith,
"Dialogues Between Humans and an Artificial Belief System"
28 pages, August 1969.

An artificial belief system capable of conducting  on-line  dialogues
with  humans  has been conntructed.   It accepts information, answers
questions and  establishes  a  credibility  for  the  information  it
acquires  and  for  its human informants.   Beginning with beliefs of
high credibility from a highly believed source, the system  is  being
subjected to the experience of dialogues with other humans.

AIM-98, CS-139, AD695401,
James Jay Horning,
"A Study of Grammatical Inference"
Thesis: Ph.D. in Computer Science,
166 pages, August 1969.

The  present  study  has been motivated by the twin goals of devising
useful inference procedures and of demonstrating a sound formal basis
for such procedures.  The former has led to the rejection of formally
simple solutions involving restrictions  which  are  unreasonable  in
practice;  the latter, to the rejection of heuristic "bags of tricks"
whose performance is in general  imponderable.   Part  I  states  the
general  grammatical  inference problem for formal languages, reviews
previous work, establishes definitions and notation,  and  states  my
position  for  a  particular  class of grammatical inference problems
based on an assumed probabilistic structure. The fundamental  results
are contained in Chapter V; the remaining chapters discuss extensions
and removal of restrictions. Part III covers  a  variety  of  related
topics, none of which are treated in any depth.

AIM-99,,,
Bruce G. Buchanan, G. L. Sutherland, E. A. Feigenbaum,
"Toward an Understanding of Information Processes of Scientific
 Inference in the Context of Organic Chemistry"
66 pages, September 1969.

The program called  Heuristic  DENDRAL  solves  scientific  induction
problems  of  the  following  type:    given  the mass spectrum of an
organic molecule, what is the most plausible  hypothesis  of  organic
structure  that  will serve to explain the given empirical data.  Its
problem solving power derives in large measure from the  vast  amount
of  chemical  knowledge  employed  in  controlling  search and making
evaluations.

A brief description of the task environment and the program is  given
in  Part I.  Recent improvements in the design of the program and the
quality of its performance  in  the  chemical  task  environment  are
noted.

The  acquisition  of  task-specific knowledge from chemist-`experts',
the representation of  this  knowledge  in  a  form  best  suited  to
facilitate  the problem solving, and the most effective deployment of
this body of knowledge in restricting search  and  making  selections
have  been  major  foci  of  our  research.   Part  II  discusses the
techniques used and problems encountered in eliciting  mass  spectral
theory  from  a cooperative chemist. A sample `scenario' of a session
with a chemist is exhibited.  Part III discusses more general  issues
of  the  representation  of  the chemical knowledge and the design of
processes that utilize it effectively.  The initial, rather straight-
forward,  implementations were found to have  serious defects.  These
are  discussed.   Part IV is  concerned with  our presently-conceived
solutions to  some of these  problems, particularly  the rigidity  of
processes and knowledge-structures.

The paper concludes with a bibliography of  publications  related  to
the DENDRAL effort.

AIM-100,,,
Zohar Manna, John McCarthy,
"Properties of Programs and Partial Function Logic"
21 pages, October 1969.

We  consider  recursive  definitions  which  consist  of   Algol-like
conditional   expressions.  By  specifying  a  computation  rule  for
evaluating  such  recursive  definition,  it  determines  a   partial
function.    However,  for  different  computation  rules,  the  same
recursive definition may determine different partial  functions.   We
distinguish  between  two types of computation rules:  sequential and
parallel.

The purpose of  this  paper  is  to  formalize  properties  (such  as
termination,  correctness  and equivlance) of these partial functions
by means of the satisfiability or validity  of  certain  formulas  in
partial function logic.

.bi
This  paper  was  presented  in the 5th Machine Intelligence Workshop
held at Edinburgh (September 15-20, 1969), and will be  published  in
<Machine Intelligence 5> (Edinburgh University Press, 1970).
.end

*AIM-101,,,
Richard Paul, G. Falk, J. A. Feldman,
"The Computer Representation of Simply Described Scenes"
16 pages, October 1969.

This paper describes the computer representation of scenes consisting
of  a  number  of  simple  three-dimensional  objects.  One method of
representing such scenes is a  space  oriented  representation  where
information  about  a region of space is accessed by its coordinates.
Another approach is to access the information by  object,  where,  by
giving the object name, its description and position are returned.

As  the description of an object is lengthy, it is desirable to group
similar objects.  Groups of similar objects  can  be  represented  in
terms  of  a  common part and a number of individual parts.  If it is
necessary to simulate moving  an  object  then  only  the  individual
information need be saved.

*AIM-102,,,
Donald A. Waterman,
"Generalization Learning for Automating the Learning of Heuristics"
74 pages, July 1969.

This paper investigates the problem of implementing machine  learning
of   heuristics.  First,  a  method  of  representing  heuristics  as
production rules is developed which facilitates dynamic  manipulation
of  the heuristics by the program embodying them.  Second, procedures
are  developed  which  permit  a  problem-solving  program  employing
heuristics   in   production  rule  form  to  learn  to  improve  its
performance by  evaluating  and  modifying  existing  heuristics  and
hypothesizing new ones, either during an explicit training process or
during normal program operation.  Third,  the  feasibility  of  these
ideas in a complex problem-solving situation is demonstrated by using
them in a program to make the bet decision in draw  poker.   Finally,
problems  which  merit further investigation are discussed, including
the problem of defining the  task  environment  and  the  problem  of
adapting the system to board games.

AIM-103,,,
John Allen, David Luckham
"An Interactive Theorem-proving Program"
27 pages, October 1969.

We present an  outline  of  the  principle  features  of  an  on-line
interative  theorem-proving  program,  and  a  brief  account  of the
results of some experiments with it.  This program has been  used  to
obtain  proofs of new mathematical results recently announced without
proof in the Notices of the American Mathematical Society.

AIM-104,,,
Joshua Lederberg, Georgia Sutherland, B. G. Buchanan, E. A. Feigenbaum,
"A Heuristic Program for Solving a Scientific Inference Problem:
 Summary of Motivation and Implementation"
15 pages, November 1969.

The  primary  motivation of the Heuristic DENDRAL project is to study
and model processes of inductive inference in science, in particular,
the  formation  of  hypotheses  which  best  explain  given  sets  of
empirical data.  The  task  chosen  for  detailed  study  is  organic
molecular  structure determination using mass spectral data and other
associated spectra.  This paper first summarizes the  motivation  and
general  outline of the approach.  Next, a sketch is given of how the
program works and how good its performance is  at  this  stage.   The
paper  concludes  with  a  comprehensive  list of publications of the
project.

*AIM-105,,,
Manfred Heuckel,
"An Operator Which Locates Edges in Digitized Pictures"
37 pages, October 1969.

This  paper  reports  the  development  of  an  edge finding operator
(subroutine) which accepts the digitized light intensities  within  a
small  disc-shaped  subarea  of a picture and yields a description of
any edge  (brightness  step)  which  may  pass  over  the  disc.   In
addition,  the  operator reports a measure of the edge's reliability.
A  theoretical  effort  disclosed  the  unique  best  operator  which
satisfies  a certain set of criteria for a local edge recognizer. The
main concerns of the  criteria  are  speed  and  reliability  in  the
presence of noise.

AIM-106,,,
Michael Edwin Kahn,
"The Near-minimum-time Control of Open-loop Articulated Kinematic
 Chains"
Thesis: Ph.D. in Mechanical Engineering,
171 pages, December 1969.

The time-optimal control of a system of  rigid  bodies  connected  in
series by single-degree-of-freedom joints is studied.

The  dynamical  equations  of  the  system are highly nonlinear and a
closed-form representation of the minimum-time  feedback  control  is
not  possible.  However, a suboptimal feedback control which provides
a close approximation to the optimal control is developed.

The suboptimal control is expressed in terms of switching curves  for
each  of  the  system  controls.  These  curves are obtained from the
linearized equations of motion for the  system.   Approximations  are
made  for  the effects of gravity loads and angular velocity terms in
the nonlinear equations of motion.

Digital simulation is used to obtain a comparison of  response  times
of the optimal and suboptimal controls.  The speed of response of the
suboptimal control is found  to  compare  quite  favorably  with  the
response speed of the optimal control.

The  analysis  is  applied  to  the  control  of  three  joints  of a
mechanical manipulator.  Modifications of the suboptimal control  for
use  in a sampled-data system are shown to result in good performance
of a hydraulic manipulator under computer control.

*AIM-107,,,
Gilbert Falk,
"Some Implications of Planarity for Machine Perception"
27 pages, December 1969.

The  problem  of  determining  the shape and orientation of an object
based on one or more two-dimensional images  is  considered.   For  a
restricted  class  of  projections  it  is   shown   that   monocular
information  is  often "nearly" sufficient for complete specification
of the object viewed.

AIM-108,,,
Michael D. Kelly,
"Edge Detection in Pictures by Computer Using Planning"
28 pages, January 1970.

This paper describes  a program for extracting an accurate outline of
a man's head from  a digital picture.   The program accepts as  input
digital, grey scale  pictures containing people standing  in front of
various  backgrounds.  The output  of the program  is an ordered list
of the  points which  form the  outline of the  head.   The edges  of
background  objects and the  interior details  of the head  have been
suppressed.

The program  is successful  because of  an improved  method for  edge
detection which  uses  heuristic planning,   a  technique drawn  from
artificial  intelligence  research  in problem  solving.    In brief,
edge detection  using  planning  consists  of three  steps.    A  new
digital picture  is prepared  from the original;  the new  picture is
smaller  and has  less detail.  Edges of  objects are located  in the
reduced picture. The edges found  in the reduced picture are  used as
a plan for finding edges in the original picture.

*AIM-109,,,
Roger C. Schank, Lawrence Tesler, Sylvia Weber,
"Spinoza II: Conceptual Case-based Natural Language Analysis"
107 pages, January 1970.

This paper  presents the theoretical  changes that have  developed in
Conceptual  Dependency  Theory and  their  ramifications  in computer
analysis of natural language.   The major  items of concern are:  the
elimination  of reliance  on  `grammar rules'  for  parsing with  the
emphasis  given to conceptual rule based  parsing, the development of
a   conceptual   case  system   to   account   for   the   power   of
conceptualizations; the categorization  of ACT's based on permissible
conceptual cases and other criteria.   These items are developed  and
discussed in the context  of a more powerful conceptual  parser and a
theory of language understanding.

*AIM-110,,,
Edward Ashcroft, Zohar Manna,
"Formalization of Properties of Parallel Programs"
58 pages, February 1970.

In this paper  we describe a  class of parallel  programs and give  a
formalization  of certain  properties of  such programs  in predicate
calculus.

Although  our programs  are  syntactically simple,   they  do exhibit
interaction between  asynchronous parallel  processes,  which is  the
essential feature we wish  to consider.  The formalization can easily
be extended to more complicated programs.

Also presented is a method  of simplifying parallel programs,   i.e.,
constructing   simpler    equivalent   programs,    based   on    the
"independence" of  statements in them.   With these simplications our
formalization gives  a  practical method  for proving  properties  of
such programs.

*AIM-111,,,
Zohar Manna,
"Second-order Mathematical Theory of Computation"
25 pages, March 1970.

In this  work we show that it is possible to formalize all properties
regularly   observed   in   (deterministic   and   non-deterministic)
algorithms in second-order predicate calculus.

Moreover, we  show that for any  given algorithm it  suffices to know
how to formalize its "partial correctness" by a second-order  formula
in order to formalize all other properties by second-order formulas.

This result  is of special  interest since "partial  correctness" has
already  been formalized in second-order  predicate calculus for many
classes of algorithms.

This paper  will  be presented  at the  ACM  Symposium on  Theory  of
Computing (May 1970).

AIM-112,,,
Franklin D. Hilf, Kenneth M. Colby, David C. Smith, William K. Wittner,
"Machine-mediated Interviewing"
27 pages, March 1970.

A  technique  of  psychiatric  interviewing  is  described  in  which
patient  and interviewer  communicate  by means  of  remotely located
teletypes. Advantages of non-nonverbal communication in the study  of
the  psychiatric interview  and  in  the  development of  a  computer
program  designed to  conduct  psychiatric interviews  are discussed.
Transcripts from representative interviews are reproduced.

*AIM-113,,,
Kenneth Mark Colby, Franklin D. Hilf, William A. Hall,
"A Mute Patient's Experience With Machine-mediated Interviewing"
19 pages, March 1970.

A  hospitalized mute  patient participated  in seven machine-mediated
interviews,   excerpts  of  which are  presented.   After  the  fifth
interview he  began to use  spoken language for  communication.  This
novel  technique  is  suggested  for  patients  who  are  unable   to
participate in the usual vis-a-vis interview.

*AIM-114,,,
Alan W. Biermann, Jerome A. Feldman,
"On the Synthesis of Finite-state Acceptors"
31 pages, April 1970.

Two  algorithms  are  presented for  solving  the  following problem:
Given a  finite-set S of  strings of  symbols,   find a  finite-state
machine  which  will  accept  the  strings of  S  and  possibly  some
additional  strings which "resemble"  those of S.   The approach used
is to directly construct  the states and transitions of  the acceptor
machine  from  the string  information.    The  algorithms include  a
parameter  which  enable  one  to  increase  the  exactness  of   the
resulting machine's  behavior as  much as  desired by increasing  the
number  of states in the  machine.  The properties  of the algorithms
are presented and illustrated with a number of examples.

The paper  gives a  method for  identifying  a finite-state  language
from a  randomly chosen finite subset  of the language if  the subset
is  large enough  and if  a bound  is known  on the number  of states
required to recognize the language.  Finally, we discuss  some of the
uses  of the  algorithms  and their  relationship to  the  problem of
grammatical inference.

AIM-115,,,
Ugo Montanari,
"On the Optimal Detection of Curves in Noisy Pictures"
35 pages, March 1970.

A technique for recognizing  systems of lines is presented,  in which
the  heuristic of  the  problem is  not embedded  in  the recognition
algorithm but  is  expressed in  a figure  of  merit.   A  multistage
decision process is  then able to recognize in the  input picture the
optimal system  of lines according to the given figure of merit.  Due
to the  global approach,   greater  flexibility and  adequacy in  the
particular problem  is achieved.  The relation  between the structure
of the  figure  of  merit  and the  complexity  of  the  optimization
process is  then discussed.   The  method described  is suitable  for
parallel  processing because  the operations  relative to  each state
can be computed  in parallel, and  the number of  stages is equal  to
the length  N of the curves  (or to log2(N) if  an approximate method
is used).

*AIM-116,,,
Kenneth Mark Colby,
"Mind and Brain, Again"
10 pages, March 1970.

Classical mind-brain questions appear deviant through the  lens of an
analogy  comparing  mental  processes with  computational  processes.
Problems  of  reducibility  and   personal  consciousness  are   also
considered in the light of this analogy.

*AIM-117,,,
John McCarthy, et al,
"Project Technical Report"
75 pages, April 1970.

Current research  is reviewed in artificial  intelligence and related
areas,    including representation  theory,   mathematical  theory of
computation, models of cognitive processes, speech  recognition,  and
computer vision.

AIM-118,,,
Ugo Montanari,
"Heuristically Guided Search and Chromosome Matching"
29 pages, April 1970.

.oi
Heuristically   guided   search   is   a   technique   which    takes
systematically into account  information from the problem  domain for
directing the search.   The problem is to find the shortest path in a
weighted graph from a start vertex Va to a goal vertex Vz:  for every
intermediate vertex, an estimate is  available of the distance to Vz.
If this  estimate satisfies a consistency assumption, an algorithm by
Hart, Nilsson and Raphael is guaranteed to find  the optimum, looking
at  the <a priori> minimum number  of  vertices.   In  this paper,  a
version of the above algorithm  is presented, which is guaranteed  to
succeed with the minimum  amount of storage.  An  application of this
technique   to  the  chromosome  matching   problem  is  then  shown.
Matching  is  the  last   stage  of  automatic  chromosome   analysis
procedures,  and can  also  solve ambiguities  in the  classification
stage. Some  peculiarities of this kind of data suggest the use of an
heuristically  guided  search  algorithm  instead  of   the  standard
Edmonds' algorithm.  The method  that we obtain in this way is proved
to exploit  the clustering  of  chromosome data:  a  linear-quadratic
dependence from the  number of chromosomes is obtained  for perfectly
clustered data.  Finally, some experimental results are given.

*AIM-119,,,
Joseph Becker,
"An Information-processing Model of Intermediate-Level Cognition"
123 pages, May 1970.

There is a large class  of cognitive operations in which an  organism
adapts its previous experience in order  to respond properly to a new
situation  -- for example:  the perceptual recognition  of objects and
events,  the prediction of  the immediate future (e.g. in  tracking a
moving object), and the  employment of sensory-motor "skills".  Taken
all together,   these  highly efficient  processes form  a  cognitive
subsystem which is  intermediate between the  low-level sensory-motor
operations   and  the   more   deliberate  processes   of  high-level
`thought'.

The present report  describes a  formal information-processing  model
of this  `Intermediate-Level' cognitive  system.  The  model includes
memory  structures for the  storage of experience,  and processes for
responding to new  events on  the basis of  previous experience.   In
addition,  the proposed  system contains a large number of mechanisms
for making the response-selection process highly efficient, in  spite
of the vast  amount of stored  information that the system  must cope
with.   These devices include procedures for heuristically evaluating
alternative subprocesses, for guiding the search through  memory, and
for  reorganizing  the  information  in memory  into  more  efficient
representations.

*AIM-120,,,
Kenneth Mark Colby, David Canfield Smith,
"Computer as Catalyst in the Treatment of Nonspeaking Autistic
 Children"
32 pages, April 1970.

Continued  experience  with  a  computer-aided treatment  method  for
nonspeaking autistic  children has  demonstrated improvement  effects
in thirteen out  of a series  of seventeen cases.   Justification for
this conclusion  is discussed in detail.   Adoption of this method by
other  research groups  is  needed  for  the  future  development  of
computer-aided treatment.

*AIM-121,,,
Irwin Sobel,
"Camera Models and Machine Perception"
Thesis: Ph.D. in Electrical Engineering,
89 pages, May 1970.

We  have  developed  a  parametric  model  for  a computer-controlled
moveable  camera  on a  pan-tilt  head.    The  model  expresses  the
transform relating object  space to image space as  a function of the
control variables  of  the  camera.   We  constructed  a  calibration
system for  measuring the model  parameters which has  a demonstrated
accuracy  more than  adequate for  our present needs.   We  have also
identified the  major source  of  error in  model measurement  to  be
undesired  image motion  and have  developed means  of measuring  and
compensating  for some of it and eliminating  other parts of it.  The
system can measure  systematic image distortions  if they become  the
major  accuracy limitation.    We have  shown how  to  generalize the
model to handle small  systematic errors due  to aspects of  pan-tilt
head geometry not presently accounted for.

We have  demonstrated the  model's application  in stereo vision  and
have shown  how it can be applied as  a predictive device in locating
objects of interest and centering them in an image.

*AIM-122,,,
Roger C. Schank,
"`Semantics' in Conceptual Analysis"
56 pages, May 1970.

.bi
This paper  examines the  question of what  a semantic  theory should
account for.   Some aspects of the work of Katz, Fillmore, Lakoff and
Chomsky  are  discussed.     <Semantics>  is  concluded  to   be  the
representation  problem with  respect  to conceptual  analysis.   The
beginnings of a solution to this  problem are presented in the  light
of developments in conceptual dependency theory.
.end

AIM-123,,,
Bruce G. Buchanan, Thomas E. Headrick,
"Some Speculation About Artificial Intelligence and Legal Reasoning"
54 pages, May 1970.

Legal reasoning is viewed here  as a complex problem-solving task  to
which the  techniques of  artificial intelligence programming  may be
applied.   Some  existing programs  are discussed  which successfully
attack various  aspects  of the  problem,   in  this and  other  task
domains.   It remains an open  question, to be  answered by intensive
research, whether computers  can be programmed  to do creative  legal
reasoning.  Regardless of the answer, it is  argued that much will be
gained by the research.

AIM-124,,,
M. M. Astrahan,
"Speech Analysis by Clustering, or the Hyperphoneme Method"
22 pages, June 1970.

In this  work, measured speech waveform data was  used as a basis for
partitioning an  utterance into  segments and  for classifying  those
segments.   Mathematical  classifications  were used  instead of  the
traditional   phonemes  or  linguistic  categories.    This  involved
clustering  methods   applied  to   hyperspace  points   representing
periodic  samples  of speech  waveforms.    The  cluster centers,  or
hyperphonemes (HPs),  were used to classify the sample points by  the
nearest-neighbor technique.  Speech segments  were formed by grouping
adjacent  points with the  same classification.   A dictionary  of 54
different words from a single  speaker was processed by this  method.
216  utterances,   representing  four more  repetitions  by the  same
speaker  each of the original 54  words, were similarly analyzed into
strings  of  hyperphonemes and  matched  against  the  dictionary  by
heuristically  developed formulas.   87%  were  correctly recognized,
although almost  no  attempt  was  made to  modify  and  improve  the
initial methods and parameters.

*AIM-125,,,
Kenneth Mark Colby, Sylvia Weber, Franklin Hilf,
"Artificial Paranoia"
35 pages, July 1970.

A case of artificial  paranoia has been synthesized in the  form of a
computer   model.    Using   the  test  operations   of  a  teletyped
psychiatric interview, clinicians judge the input-output behavior  of
the  model to  be  paranoid.   Formal validation  of  the model  will
require experiments involving indistinguishability tests.

AIM-126, CS-169, AD711329,
Donald E. Knuth,
"Examples of Formal Semantics"
34 pages, July 1970.

A  technique  of formal  definition,    based  on  relations  between
`attributes'  associated with nonterminal  symbols in  a context-free
grammar,  is  illustrated  by  several  applications  to  simple  yet
typical problems.   First we  define the  basic properties of  lambda
expressions, involving  substitution and renaming of bound variables.
Then  a  simple  programming   language  is  defined  using   several
different points  of view.   The emphasis is on  `declarative' rather
than `imperative' forms of definition.

AIM-127, CS-174, AD711395,
Zohar Manna, Richard J. Waldinger,
"Towards Automatic Program Synthesis"
54 pages, July 1970.

An  elementary outline  of the theorem-proving  approach to automatic
program synthesis  is given, without  dwelling on technical  details.
The  method is  illustrated  by the  automatic  construction of  both
recursive  and  iterative  programs  operating  on  natural  numbers,
lists, and trees.

In order to construct a program  satisfying certain specifications, a
theorem induced  by those specifications is proved,   and the desired
program is extracted from the  proof.  The same technique is  applied
to transform  recursively defined functions into  iterative programs,
frequently with a major gain in efficiency.

It  is emphasized that in order to  construct a program with loops or
with recursion,   the  principle  of mathematical  induction must  be
applied.   The  relation between  the version  of the  induction rule
used and the  form of  the program  constructed is  explored in  some
detail.

AIM-128, CS-166, AD713841,
Erik J. Sandewall,
"Representing Natural-language Information in Predicate Calculus"
27 pages, July 1970.

A  set of general  conventions are proposed  for representing natural
language information in many-sorted  first order predicate  calculus.
The  purpose is  to provide  a testing-ground  for existing  theorem-
proving programs.

*AIM-129, CS-167, AD712460,
Shigeru Igarashi,
"Semantics of ALGOL-like Statements"
95 pages, June 1970.

The  semantics of  elementary  Algol-like  statements  is  discussed,
mainly based on an axiomatic method.

Firstly,    a  class   of  Algol-like  statements  is  introduced  by
generalized inductive  definition,   and  the interpretation  of  the
statements belonging to it is defined in the  form of a function over
this  class,   using  the induction  principle induced  by  the above
definition.  Then  a category of  program is  introduced in order  to
clarify the  concept of  equivalence of  statements, which  becomes a
special case of isomorphism in that category.

A  revised formal system  representing the concept  of equivalence of
Algol-like  statements   is  presented,     followed  by   elementary
metatheorems.

Finally,  a process  of decomposition of Algol-like statements, which
can be  regarded  as  a  conceptual  compiler,    or  a  constructive
description of semantics  based on primitive actions, is  defined and
its  correctness is  proved formally,    by the  help of  the induced
induction principle.

AIM-130, CS-168, AD713252,
Michael D. Kelly,
"Visual Identification of People by Computer"
Thesis: Ph.D. in Computer Science,
238 pages, July 1970.

This thesis  describes a computer  program which  performs a  complex
picture processing  task.  The task  is to choose, from  a collection
of  pictures of  people  taken by  a TV  camera, those  pictures that
depict the same  person.   The primary purpose  of this research  has
been directed  toward the development  of new techniques  for picture
processing.

In brief, the program works by finding the location of features  such
as eyes,   nose,   or  shoulders in  the pictures.   Individuals  are
classified  by measurements between  such features.   The interesting
and difficult  part  of  the work  reported  in this  thesis  is  the
detection  of  those  features  in digital  pictures.    The  nearest
neighbor method  is used for identification of individuals once a set
of measurements has been obtained.

The success of  the program is due  to and illustrates the  heuristic
use  of  context and  structure.   A  new,  widely useful,  technique
called planning has been applied to picture processing.  Planning  is
a  term which  is  drawn  from  artificial intelligence  research  in
problem solving.

The  principal positive result of  this research is the  use of goal-
directed techniques  to  successfully locate  features  in  cluttered
digital pictures.   This success has been verified  by displaying the
results  of  the  feature  finding  algorithms  and  comparing  these
locations with the locations obtained by hand  from digital printouts
of   the  pictures.     Successful   performance  in   the   task  of
identification  of  people  provides  further  verification  for  the
feature finding algorithms.

AIM-131, CS-176, AD715128,
Edward A. Feigenbaum, Bruce G. Buchanan, Joshua Lederberg,
"On Generality and Problem Solving: a Case Study Using the Dendral
 Program"
48 pages, August 1970.

Heuristic DENDRAL is  a computer program written to solve problems of
inductive inference in  organic chemistry.  This  paper will use  the
design  of  Heuristic  DENDRAL   and  its  performance  on  different
problems  for a discussion  of the  following topics:
.bs
1. the design for generality;

2. the performance problems attendent  upon too much generality

3. the  coupling of  expertise to  the  general problem solving
   processes,

4. the symbiotic relationship between generality  and  expertnness of
   problem solving systems.
.end

We  conclude the  paper  with a  view  of the  design  for a  general
problem  solver  that is  a variant  of  the "big  switch"  theory of
generality.

*AIM-132, CS-180, AD715665,
Gilbert Falk,
"Computer Interpretation of Imperfect Line Data as a Three-dimensional
 Scene"
Thesis: Ph.D. in Electrical Engineering,
187 pages, August 1970.

The  major  portion  of  this   paper  describes  a  heuristic  scene
description  program.     This  program  accepts  as  input  a  scene
represented as  a  line drawing.   Based  on a  set  of known  object
models the  program attempts to  determine the identity  and location
of each object viewed.  The  most significant feature of the  program
is its ability to deal with imperfect input data.

We also  present some preliminary  results concerning  constraints in
projections  of planar-faced solids.   We show that  for a restricted
class of  projects,   4  points located  in  3-space in  addition  to
complete  monocular information  are  sufficient to  specify all  the
visible point locations precisely.

*AIM-133, CS-181,,
Anthony C. Hearn,
"Reduce 2"
Diskfile: REDUCE.ACH[AIM,DOC],
85 pages, October 1970.

This  manual provides  the user with  a description  of the algebraic
programming  system  REDUCE 2.    The  capabilities  of  this  system
include:
.bs
1) Expansion and ordering of rational functions of polynomials,

2) symbolic differentiation of rational  functions of polynomials and
   general functions,

3)  substitutions  and  pattern matching in  a wide variety of forms,

4) calculation of the greatest common divisor of two  polynomials,

5) automatic and user  controlled simplification   of  expressions,

6)  calculations   with  symbolic matrices,

7) a complete language for symbolic calculations, in which the REDUCE
   program itself is written,

8) calculations of interest to high  energy physicists including spin
   1/2 and spin 1 algebra,

9) tensor operations.
.end


*AIM-134, CS-182, AD748565,
Jay Martin Tenenbaum,
"Accommodation in Computer Vision"
Thesis: Ph.D. in Electrical Engineering,
452 pages, September 1970.

We  describe  an  evolving  computer  vision  system  in  which   the
parameters of  the  camera are  controlled by  the computer.   It  is
distinguished  from conventional  picture  processing systems  by the
fact  that sensor  accommodation  is  automatic  and  treated  as  an
integral part of the recognition process.

A machine,   like a  person,  comes in  contact with far  more visual
information  than it  can process.   Furthermore, no  physical sensor
can simultaneously provide  information about the  full range of  the
environment.   Consequently,  both man  and machine  must accommodate
their  sensors   to  emphasize   selected  characteristics   of   the
environment.

Accommodation  improves the  reliability  and efficiency  of  machine
perception  by matching the  information provided by  the sensor with
that required by  specific perceptual functions.   The advantages  of
accommodation are demonstrated  in the context of  five key functions
in  computer vision:  acquisition, contour following,   verifying the
presence of an expected edge, range-finding, and color recognition.

We have  modeled  the interaction  of  camera parameters  with  scene
characteristics to  determine the composition  of an image.   Using a
priori knowledge of the environment,  the camera is tuned to  satisfy
the information requirements of a particular task.

Task  performance  depends  implicitly  on   the  appropriateness  of
available information.   If a function fails  to perform as expected,
and if this failure is  attributable to a specific image  deficiency,
then the relevant accommodation parameters can be refined.

This schema for  automating sensor accommodation can be  applied in a
variety of perceptual domains.

AIM-135, CS-179, AD716566,
David Canfield Smith,
"MLISP"
Diskfile: MLISP.DAV[AIM,DOC]
99 pages, October 1970.

MLISP  is  a  high  level   list-processing  and  symbol-manipulation
language based  on the programming language  LISP.  MLISP programs are
translated into LISP  programs and then  executed or compiled.  MLISP
exists  for  two   purposes:  (1)  to  facilitate   the  writing  and
understanding  of  LISP  programs; (2)  to  remedy  certain important
deficiencies in the list-processing ability of LISP.


*AIM-136, CS-183, AD717600,
George M. White,
"Machine Learning Through Signature Trees. Applications to Human
 Speech"
40 pages, October 1970.

Signature  tree  `machine learning',  pattern  recognition heuristics
are investigated for the specific problem of computer  recognition of
human  speech.     When  the   data  base  of  given   utterances  is
insufficient to  establish trends with confidence,  a large number of
feature extractors must be  employed and `recognition' of  an unknown
pattern  made by  comparing its  feature values  with those  of known
patterns. When the data  base is replete, a  `signature' tree can  be
constructed and recognition  can be achieved  by the evaluation  of a
select  few features.   Learning  results  from selecting  an optimal
minimal set  of  features  to  achieve recognition.    Properties  of
signature trees and  the heuristics for this type of  learning are of
primary interest in this exposition.

*AIM-137,,,
Donald E. Knuth,
"An Empirical Study of Fortran in Use"
44 pages, November 1970.

A sample  of programs, written in Fortran by a wide variety of people
for a  wide variety  of applications, was  chosen `at  random' in  an
attempt  to  discover quantitatively  `what  programmers really  do'.
Statistical results of this survey are presented here, together  with
some  of their  apparent  implications for  future  work in  compiler
design.    The  principle  conclusion  which  may  be  drawn  is  the
importance of  a  program  `profile',  namely a  table  of  frequency
counts  which record  how  often  each statement  is  performed in  a
typical  run:  there  are  strong  indications  that  profile-keeping
should  become a  standard  practice  in all  computer  systems,  for
casual users as  well as system programmers.   Some new approaches to
compiler optimization are also suggested.   This paper is the  report
of a  three month study  undertaken by the  author and about  a dozen
students  and  representatives of  the software  industry  during the
summer of 1970.
AIM-138, CS-188, PB197161,
Edward Ashcroft, Zohar Manna,
"The Translation of `GO-TO' Programs to `WHILE' Programs"
28 pages, January 1971.

.bi
In this paper  we show that  every flowchart  program can be  written
without "go-to"  statements by  using "while"  statements.   The main
idea is  to introduce new variables to preserve the values of certain
variables at particular points  in the program; or  alternatively, to
introduce  special boolean  variables to  keep information  about the
course of the computation.

The "while"  programs produced yield  the same  final results as  the
original  flowchart  program  but need  not  perform  computations in
exactly the  same  way.    However, the  new  programs  preserve  the
<topology> of  the original  flowchart program, and  are of  the same
order of efficiency.

We  also show  that this  cannot  be done  in general  without adding
variables.
.end

AIM-139, CS-189, AD717601,
Zohar Manna,
"Mathematical Theory of Partial Correctness"
24 pages, January 1971.

.bi
In this work we show that  it is possible to express most  properties
regularly observed  in algorithms  in terms of  <partial correctness>
(i.e.,   the  property that  the final  results of the  algorithm, if
any, satisfy some  given input-output relation).

This result  is of special  interest since <partial  correctness> has
already  been   formulated  in  predicate  calculus  and  in  partial
function logic for many classes of algorithms.
.end

*AIM-140, CS-193,,
Roger C. Schank,
"Intention, Memory, and Computer Understanding"
59 pages, January 1971.

Procedures  are  described for discovering the intention of a speaker
by relating the Conceptual Dependence representation of the speaker's
utterance to the computer's world model such that simple implications
can be made.  These procedures function at levels higher than that of
structure of the memory.  Computer understanding of natural  language
is  shown  to consist of the following parts:  assigning a conceptual
representation to an  input;  relating  that  representation  to  the
memory such as to extract the intention of the speaker; and selecting
the correct response type triggered by such an utterance according to
the situation.

*AIM-141, CS-203, AD730506,
Bruce G. Buchanan, Joshua Lederberg,
"The Heuristic DENDRAL Program for Explaining Empirical Data"
20 pages, February 1971.

The Heuristic DENDRAL program uses an information processing model of
scientific   reasoning   to  explain  experimental  data  in  organic
chemistry. This report summarizes the organization and results of the
program  for  computer scientists.  The program is divided into three
main parts: planning, structure generation, and evaluation.

The planning phase infers constraints on the search  space  from  the
empirical  data  input to the system.  The structure generation phase
searches a tree whose termini are models  of  chemical  models  using
pruning  heuristics of various kinds.  The evaluation phase tests the
candidate structures against  the  original  data.   Results  of  the
program's analyses of some tests are discussed.

AIM-142, CS-205, AD731383,
Robin Milner,
"An Algebraic Definition of Simulation Between Programs"
21 pages, February 1971.

A  simulation  relation  between  programs  is   defined   which   is
quasi-ordering.    Mutual simulation is then an equivalence relation,
and by dividing out by it we abstract from a program such details  as
how  the  sequencing  is controlled and how data is represented.  The
equivalence classes are approximations to the  algorithms  which  are
realized, or expressed, by their member programs.

A  technique  is  given  and  illustrated  for proving simulation and
equivalence of programs; there is an analogy with  Floyd's  technique
for   proving   correctness  of  programs.   Finally,  necessary  and
sufficient conditions for simulation are given.

*AIM-143, CS-209, AD724867,
John McCarthy, et al,
"Project Technical Report"
80 pages, March 1971.

An  overview  is  presented  of  current  research  at  Stanford   in
artificial  intelligence  and  heuristic programming.  This report is
largely the text of a proposal  to  the  Advanced  Research  Projects
Agency for fiscal years 1972-3.

AIM-144, CS-219,,
Lynn H. Quam,
"Computer Comparison of Pictures"
Thesis: Ph.D. in Computer Science,
120 pages, May 1971.

This   dissertation  reports  the  development  of  digital  computer
techniques  for  detecting  changes  in  scenes  by  normalizing  and
comparing  pictures  which were taken from different camera positions
and under different conditions  of  illumination.  The  pictures  are
first  geometrically normalized to a common point of view.  Then they
are photometrically normalized to eliminate the  differences  due  to
different   illumination,  camera  characteristics,  and  reflectance
properties of the scene due to different sun and view angles.   These
pictures  are  then  geometrically registered by maximizing the cross
correlation  between  areas  in  them.   The  final  normalized   and
registered pictures are then differenced point by point.

The  geometric  normalization  techniques require relatively accurate
geometric models for the camera and the  scene,  and  static  spatial
features  must  be present in the pictures to allow precise geometric
alignment using the technique of cross correlation maximization.

Photometric normalization also requires a relatively  accurate  model
for  the  photometric response of the camera, a reflectance model for
the scene (reflectance as a function of the  illumination  view,  and
phase  angles)  and  some  assumptions about the kinds of reflectance
changes which are to be detected.

These techniques have been incorporated in  a  system  for  comparing
Mariner 1971 pictures of Mars to detect variable surface phenomena as
well as color and polarization  differences.   The  system  has  been
tested using Mariner 6 and 7 pictures of Mars.

Although the techniques described in this dissertation were developed
for Mars pictures, their use is  not  limited  to  this  application.
Various  parts  of  this  software  package,  which was developed for
interactive use on the time-sharing system of the Stanford Artificial
Intelligence Project, are currently being applied to other scenery.

*AIM-145, CS-221, AD731729,
Bruce G. Buchanan, Edward A. Feigenbaum, Joshua Lederberg,
"A Heuristic Programming Study of Theory Formation in Science"
41 pages, June 1971.

The Meta-DENDRAL program is a a  vehicle  for  studying  problems  of
theory formation in science.  The general strategy of Meta-DENDRAL is
to reason from data to plausible generalizations and then to organize
the  generalizations  into  a unified theory.  Three main subproblems
are discussed: (1) explain the experimental data for each  individual
chemical structure, (2) generalize the results from each structure to
all structures, and (3) organize the generalizations into  a  unified
theory.   The  program  is  built  upon  the  concepts and programmed
routines already  available  in  the  Heuristic  DENDRAL  performance
program,  but  goes  beyond  the performance program in attempting to
formulate the theory which the performance program will use.

AIM-146, CS-224, PB212183,
Andrei P. Ershov,
"Parallel Programming"
14 pages, July 1971.

This  report is based on lectures given at Stanford University by Dr.
Ershov in November, 1970.

*AIM-147, CS-216, AD732457,
Robert E. Kling,
"Reasoning by Analogy with Applications to Heuristic Problem Solving:
 a Case Study"
Thesis: Ph.D. in Computer Science,
191 pages, August 1971.

An  information-processing  approach  to  reasoning  by  analogy   is
developed  that  promises  to  increase  the  efficiency of heuristic
deductive problem-solving systems.  When  a deductive problem-solving
system  accesses a  large set  of axioms more  than sufficient  for a
particular problem,  it will often create many  irrelevant deductions
that saturate the memory of the problem solver.

Here,  an  analogy  with  some  previously  solved  problem and a new
unsolved problem is used to restrict the data base to a small set  of
appropriate  axioms.  This procedure (ZORBA) is studied in detail for
a resolution theorem proving system.  A set of  algorithms  (ZORBA-I)
which  automatically  generates  an  analogy  between  a new unproved
theorem, T↓A, and a previously proved theorem,  T,  is  described  in
detail. ZORBA-I is implemented in LISP on a PDP-10.

ZORBA-I is examined in terms of its empirical performance on parts of
analogous theorems drawn from abstract algebra.   Analytical  studies
are  included  which show that ZORBA-I can be useful to aid automatic
theorem proving in many pragmatic cases while it may be  a  detriment
in certain specially contrived cases.

AIM-148, CS-217, AD731730,
Edward Ashcroft, Zohar Manna, Amir Pneuli,
"Decidable Properties of Monadic Functional Schemas"
10 pages, July 1971.

We  define  a  class  of  (monadic) functional schemas which properly
include `Ianov' flowchart schemas.  We  show  that  the  termination,
divergence and freedom problems for functional schemas are decidable.
Although it is possible  to  translate  a  large  class  of  non-free
functional  schemas  into equivalent free functional schemas, we show
that this  cannot  be  done  in  general.   We  show  also  that  the
equivalence  problem  for free functional schemas is decidable.  Most
of  the  results  are  obtained from  well-known  results  in  Formal
Languages and Automata Theory.

AIM-149, CS-231, AD732644,
Rodney Albert Schmidt, Jr.,
"A Study of the Real-time Control of a Computer-driven Vehicle"
Thesis: Ph.D. in Electrical Engineering,
180 pages, August 1971.

Vehicle  control  by  the  computer  analysis  of  visual  images  is
investigated.   The  areas  of  guidance,  navigation,  and  incident
avoidance  are  considered.  A television camera is used as the prime
source of visual image data.

In the guidance system developed for an experimental vehicle,  visual
data  is  used to gain information about the vehicle system dynamics,
as well as to guide the vehicle.  This information is  used  in  real
time  to  improve performance of the non-linear, time-varying vehicle
system.

A scheme for navigation by pilotage through the  recognition  of  two
dimensional  scenes  is developed.  A method is proposed to link this
to a computer-modelled map in order to make journeys.

Various difficulties in avoiding anomolous incidents in the automatic
control  of  automobiles are discussed, together with suggestions for
the application of this  study  to  remote  exploration  vehicles  or
industrial automation.

*AIM-150,,,
Robert W. Floyd,
"Toward Interactive Design of Correct Programs"
12 pages, September 1971.

We  propose  an  interactive  system  proving  the  correctness  of a
program, or locating errors, as the program is designed.

*AIM-151, CS-240, AD738568,
Ralph L. London,
"Correctness of Two Compilers for a LISP Subset"
41 pages, October 1971.

Using  mainly  structural induction, proofs of correctness of each of
two running  Lisp  compilers  for  the  PDP-10  computer  are  given.
Included  are the rationale for presenting these proofs, a discussion
of the proofs, and the changes  needed  to  the  second  compiler  to
complete its proof.

*AIM-152, CS-241, AD732642,
Alan W. Biermann,
"On the Inference of Turing Machines from Sample Computations"
31 pages, October 1971.

An  algorithm is presented which when given a complete description of
a set of Turing machine computations finds a Turing machine which  is
capable of doing those computations.  This algorithm can serve as the
basis for designing a trainable  device  which  can  be  trained   to
simulate  any  Turing machine by being led through a series of sample
computations done by that machine.  A number of examples  illustrate
the  use  of  the technique and the possibility of the application to
other types of problems.

*AIM-153, CS-242, AD738569,
Patrick J. Hayes,
"The Frame Problem and Related Problems in Artificial Intelligence"
18 pages, November 1971.

The frame problem arises in considering the logical  structure  of  a
robot's beliefs.  It has been known for some years, but only recently
has much progress been made.  The problem is described and discussed.
Various   suggested  methods  for  its  solution  are  outlined,  and
described in a uniform notation.   Finally,  brief  consideration  is
given  to  the  problem  of  adjusting a belief system in the face of
evidence which contradicts beliefs.  It is shown that a variation  on
the  situation  notation  of  (McCarthy  and  Hayes, 1969) permits an
elegant approach, and relates this problem to the frame problem.

*AIM-154, CS-243, AD738570,
Zohar Manna, Stephen Ness, Jean Vuillemin,
"Inductive Methods for Proving Properties of Programs"
24 pages, November 1971.

We  have  two  main  purposes  in  this paper.  First, we clarify and
extend  known  results  about  computation  of  recursive   programs,
emphasizing  the  difference  between  the  theoretical and practical
approaches.  Secondly, we present and examine various  known  methods
for  proving  properties of recursive programs.  We discuss in detail
two  powerful  inductive   methods,   computational   induction   and
structural  induction,  illustrating  their  applications  by various
examples. We also briefly discuss some other related methods.

Our aim in this work is to introduce inductive methods to as  wide  a
class  of  readers  as  possible  and  to  demonstrate their power as
practical  techniques.  We  ask   the   forgiveness   of   our   more
theoretical-minded  colleagues  for  our occasional choice of clarity
over precision.

AIM-155, CS-245,,
Jonathan Leonard Ryder,
"Heuristic Analysis of Large Trees as Generated in the Game of Go"
Thesis: Ph.D. in Computer Science,
300 pages, December 1971.

The  Japanese  game  of  Go  is  of  interest  both  as  a problem in
mathematical repesentation and as a game which generates a move  tree
with  an  extraordinarily  high branching factor (100 to 300 branches
per ply).  The complexity of Go (and the difficulty of Go  for  human
players)  is  thought  to be considerably greater than that of chess.
The constraints of being able to play a complete game  and  of  being
able to produce a move with a moderate amount of processing time were
placed on the solution.

The basic approach  used  was  to  find  methods  for  isolating  and
exploring  several  sorts  of relevant subsections of the global game
tree.  This process depended heavily on the  ability  to  define  and
manipulate  the  entities of Go as recursive functions rather than as
patterns of stones. A general machine-accessible  theory  of  Go  was
developed to provide context for program evaluations.

A  program  for  playing  Go  is now available on the Stanford PDP-10
computer.  It will play a  complete  game,  taking  about  10  to  30
seconds for an average move.  The quality of play is better than that
of a beginner in many respects, but incompletenesses in  the  current
machine-representable  theory  of Go prevent the present program from
becoming a strong player.

AIM-156, CS-246, AD740141,
Kenneth Mark Colby, Franklin D. Hilf, Sylvia Weber, Helena C. Kraemer,
"A Resemblance Test for the Validation of a Computer Simulation of
 Paranoid Processes"
29 pages, November 1971.

A computer simulation of paranoid processes in the form of a dialogue
algorithm  was  subjected to a validation study using an experimental
resemblance test in which judges rate  degrees of paranoia present in
initial  psychiatric  interviews  of  both  paranoid  patients and of
versions of the paranoid model.  The statistical results  indicate  a
satisfactory   degree  of  resemblance  between  the  two  groups  of
interviews. It is concluded that  the  model  provides  a  successful
simulation of naturally occuring paranoid processes.

*AIM-157, CS-247,,
Yorick Wilks,
"One Small Head -- Some Remarks on the use of `Model' in Linguistics"
17 pages, December 1971.

I argue that the present situation in formal linguistics, where  much
new  work  is presented as being a "model of the brain", or of "human
language behavior", is  an  undesirable  one.   My  reason  for  this
judgement  is  not  the  conservative  (Braithwaitian)  one  that the
entities in question are not  really  models  but  theories.   It  is
rather that they are called models because they cannot be theories of
the brain at the present stage of brain research, and hence that  the
use  of  "model"  in  this  context  is  not  so much aspirational as
resigned about our total  ignorance  of  how  the  brain  stores  and
processes   linguistic   information.  The  reason  such  explanatory
entities cannot be theories is  that  this  ignorance  precludes  any
"semantic  ascent" up the theory; i.e., interpreting the items of the
theory in terms of observables.  And the brain items,  whatever  they
may  be,  are  not,  as  Chomsky  has  sometimes claimed, in the same
position as the "occult entities" of Physics  like  Gravitation;  for
the brain items are not theoretically unreachable, merely unreached.

I  then  examine  two  possible  alternate  views  of what linguistic
theories should be proffered as theories of:   theories  of  sets  of
sentences, and theories of a particular class of algorithms.  I argue
for a form of the latter view, and that  its  acceptance  would  also
have the effect of making Computational Linguistics a central part of
Linguistics, rather than the poor relation it is now.

I examine a distinction among `linguistic models'  proposed  recently
by   Mey.   who   was   also  arguing  for  the  self-sufficiency  of
Computational Linguistics, though as a `theory  of  performance'.   I
argue  that  his  distinction  is  a  bad one, partly for the reasons
developed above and partly because he attempts to tie it to Chomsky's
inscrutable  competance-performance distinction.  I conclude that the
independence and self-sufficiency of  Computational  Linguistics  are
better supported by the arguments of this paper.

AIM-158, CS-250, AD740127,
Ashok Chandra, Zohar Manna,
"Program Schemas With Equality"
13 pages, December 1971.

We discuss the class  of  program  schemas  augmented  with  equality
tests,  that  is, tests of equality between terms.

In the first part of the paper we  illustrate the `power' of equality
tests.  It  turns out that the class of program schemas with equality
is more powerful than the  `maximal' classes of schemas suggested  by
other investigators.

In the second part of the  paper, we discuss the decision problems of
program  schemas with  equality.  It is  shown,   for example,   that
while the decision problems normally considered for  schemas (such as
halting,  divergence,   equivalence,   isomorphism  and  freedom) are
decidable for Ianov schemas.  They all become undecidable if  general
equality tests  are added.   We suggest,  however,  limited  equality
tests  which can be  added to  certain subclasses of  program schemas
while preserving their solvable properties.

AIM-159, CS-253,,
Jerome A. Feldman, Paul C. Shields,
"Total Complexity and Inference of Best Programs"
40 pages, April 1972.

Axioms  for  a  total  complexity  measure  for abstract programs are
presented. Essentially, they require  that  total  complexity  be  an
unbounded  increasing  function  of  the Blum time and size measures.
Algorithms for finding the  best  program  on  a  finite  domain  are
presented,   and   their   limiting  behavior  for  infinite  domains
described.  For total complexity, there are important senses in which
a machine can find the best program for a large class of functions.

*AIM-160, CS-255, AD740140,
Jerome A. Feldman,
"Automatic Programming"
20 pages, February 1972.

The revival of interest in Automatic Programming is  considered.  The
research  is divided into direct efforts and theoretical developments
and the successes and prospects of each are described.

AIM-161, CS-264, AD741189,
Yorick Wilks,
"Artificial Intelligence approach to Machine Translation"
44 pages, February 1972.

The paper describes a system of  semantic  analysis  and  generation,
programmed  in  LISP  1.5  and designed to pass from paragraph length
input in English to French via  an  interlingual  representation.   A
wide class of English input forms will be covered, but the vocabulary
will initially be restricted to one of a  few  hundred  words.   With
this  subset  working,  and  during the current year (1971-72), it is
also hoped to map the interlingual representation onto some predicate
calculus notation so as to make possible the answering of very simple
questions about the translated  matter.   The  specification  of  the
translation system itself is complete, and its main points are:

i) It translates phrase by  phrase--with  facilities  for  reordering
phrases  and  establishing  essential semantic connectivities between
them--by mapping complex semantic stuctures of  "message"  onto  each
phrase.  These  constitute  the  interlingual  representation  to  be
translated.  This matching is done without  the  explicit  use  of  a
conventional  syntax  analysis,  by taking as the appropriate matched
structure the `most dense' of  the  alternative  structures  derived.
This  method  has been found highly successful in earlier versions of
this analysis system.

.bi
ii) The French output strings are generated without the explicit  use
of  a  generative  grammar.   That  is  done by means of <stereotypes:>
strings of French words, and functions evaluating  to  French  words,
which are attached to English word senses in the dictionary and built
into the interlingual representation by the analysis  routines.   The
generation  program thus receives an interlingual representation that
already contains both  French  output  and  implicit  procedures  for
assembling  the output, since the stereotypes are in effect recursive
procedures specifying the content and production of the  output  word
strings.   Thus  the  generation  program  at no time consults a word
dictionary or inventory of grammar rules.

It  is  claimed that the system of notation and translation described
is a convenient one for expressing and handling the items of semantic
information that are <essential> to any effective MT system.  I discuss
in some detail the semantic information needed to ensure the  correct
choice  of output prepositions in French; a vital matter inadequately
treated by virtually all previous formalisms and projects.
.end

*AIM-162, CS-265, AD744634,
Roger C. Schank, N. Goldman, C. J. Rieger, C. K. Riesbeck,
"Primitive Concepts Underlying Verbs of Thought"
102 pages, April 1972.

In  order  to  create  conceptual  structures  that will uniquely and
unambiguously represent the meaning of an utterance, it is  necessary
to  establish  `primitive'  underlying  actions and states into which
verbs can be mapped.  This paper presents analyses of the most common
mental  verbs in terms of such primitive actions and states. In order
to represent the way people speak about their  mental  processes,  it
was  necessary  to  add  to  the  usual ideas of memory structure the
notion of Immediate Memory.  It is then argued that  there  are  only
three primitive mental ACTs.

AIM-163, CS-266,,
Jean M. Cadiou,
"Recursive Definitions of Partial Functions and Their Computations"
Thesis: Ph.D. in Computer Science,
160 pages, April 1972.

A formal syntactic and semantic model  is  presented  for  `recursive
definitions'  which  are  generalizations of those found in LISP, for
example.   Such  recursive  definitions  can  have  two  classes   of
fixpoints,  the  strong  fixpoints  and  the weak fixpoints, and also
possess a class of computed partial functions.

Relations between  these classes are  presented: fixpoints  are shown
to  be  extensions of  computed  functions.   More  precisely, strong
fixpoints are shown to be  extensions of computed functions when  the
computations  may   involve  `call   by  name'   substitutions;  weak
fixpoints  are shown to be extensions  of computed functions when the
computation  only  involve  `call  by  value'   substitutions.    The
Church-Rosser property for  recursive definitions with fixpoints also
follows from these results.

Then conditions are given on the recursive definitions to ensure that
they possess least fixpoints (of both classes), and computation rules
are given for computing these two fixpoints:  the `full'  computation
rule,  which  leads  to  the least weak fixpoint.  A general class of
computation rules, called `safe innermost', also lead to  the  latter
fixpoint.   The "leftmost innermost" rule is a special case of those,
for the LISP recursive definitions.

AIM-164, CS-272, AD742748,
Zohar Manna, Jean Vuillemin,
"Fixpoint Approach to the Theory of Computation"
29 pages, April 1972.

Following the  fixpoint theory  of Scott,  we propose  to define  the
semantics  of computer programs  in terms  of the least  fixpoints of
recursive programs. This allows one not only to justify  all existing
verification techniques,  but also to  extend them to  handle various
properties  of computer programs,  including correctness, termination
and equivalence, in a uniform manner.

*AIM-165, CS-280, AD742751,
D. A. Bochvar,
"Two Papers on Partial Predicate Calculus"
50 pages, April 1972.

These  papers,  published  in  1938  and   1943,  contain  the  first
treatment of  a logic of partial predicates.   Bochvar's treatment is
of current interest  for two reasons.   First, partial predicate  and
function logic  are important for mathematical  theory of computation
because  functions  defined by  programs  or by  recursion  cannot be
guaranteed to  be  total.   Second, natural  language  may be  better
approximated  by a  logic in  which some  sentences may  be undefined
than by a  conventional logic.   Bochvar use of  his system to  avoid
Russell's  paradox is  of  interest here,  and  in partial  predicate
logic  it may be possible  to get more of  an axiomatization of truth
and knowledge than in a conventional logic.

.bi
The papers  translated are  "On a  three-valued logical calculus  and
its   application  to   the  analysis  of   contradictions", <Recueil
Mathematique>, N. S. 4 (1938),  pp. 287-308,  and "On the  consistency
of a three-valued logical calculus", ibid. 12 (1943), pp. 353-369.
.end

We  also print  a  review  and a  correction  by Alonzo  Church  that
appeared  in the Journal of  Symbolic Logic.  The  review was in Vol.
4.2 (June 1939), p.  99, and the additional  comment was in Vol. 5.3
(September 1940), p. 119.

AIM-166, CS-281, AD-743598,
Lynn H. Quam, S. Liebes, R. B. Tucker, M. J. Hannah, B. G. Eross,
"Computer Interactive Picture Processing"
40 pages, April 1972.

This  report  describes  work  done  in  image  processing  using  an
interactive  computer  system.  Techniques for image differencing are
described and examples using images returned from Mars by the Mariner
Nine  spacecraft are shown.  Also described are techniques for stereo
image processing.  Stereo processing  for  both  conventional  camera
systems and the Viking 1975 Lander camera system is reviewed.

AIM-167, CS-282, AD747254,
Ashok K. Chandra,
"Efficient Compilation of Linear Recursive Programs"
43 pages, June 1972.

.begin turn on "%#↑[]"; at "<" ⊂"%6"⊃; at ">" ⊂"%1"⊃;
We  consider  the  class  of  linear  recursive  programs.   A linear
recursive program is a set of procedures  where  each  procedure  can
make   at   most   one   recursive   call.   The  conventional  stack
implementation of recursion requires time and space both proportional
to  n,  the  depth  of  recursion.    It  is  shown  that in order to
implement linear recursion so as to execute in  time  n  one  doesn't
need space proportional to n#:#n<↑ε> for sufficiently small <ε> will do.
It is also known that with constant space one  can  implement  linear
recursion  in  time  n<↑2>.   We  show  that  one  can do much better:
n<↑[1+ε]> for arbitrarily small <ε>.  We also describe an algorithm that
lies between thee two:  it takes time n#log(n) and space log(n).
.end

It  is  shown that several problems are closely related to the linear
recursion problem, for example, the problem  of  reversing  an  input
tape given a finite automaton with several one-way heads.  By casting
all these problems  into  canonical  form,  efficient  solutions  are
obtained simultaneously for all.

AIM-168, CS-287, AD746146,
Shigeru Igarashi,
"Admissibility of Fixed-point Induction in First-order Logic of Typed 
 Theories"
Diskfile: FIXPNT.IGR[AIM,DOC]
40 pages, May 1972.

First-order logic is extended so as  to  deal  with  typed  theories,
especially  that  of  continuous functions with fixed-point induction
formalized by D. Scott.  The translation of his formal system, or the
λ calculus-oriented system derived and implemented by R. Milner, into
this logic amounts to adding predicate calculus features to them.

In such a logic the fixed-point induction axioms are no longer valid,
in  general,  so  that  we characterize formulas for which Scott-type
induction is applicable, in terms of syntax which can be checked
by machines automatically.

AIM-169, CS-288,,
Robin Milner,
"Logic for Computable Functions: Description of a Machine Implementation"
Diskfile: LCFMAN.RGM[AIM,DOC],
36 pages, May 1972.

This paper is primarily a user's manual  for  LCF,  a  proof-checking
program for a logic of computable functions proposed by Dana Scott in
1969, but unpublished by him.  We use the name LCF also for the logic
itself,   which  is  presented  at  the  start  of  the  paper.   The
proof-checking program is designed to allow the user interactively to
generate  formal  proofs  about  computable functions and functionals
over a variety  of  domains,  including  those  of  interest  to  the
computer   scientist -- for   example,  integers,  lists  and  computer
programs and their semantics. The user's task is  alleviated  by  two
features:   a  subgoaling  facility  and  a  powerful  simplification
mechanism.  Applications include proofs of program correctness and in
particular  of  compiler  correctness;  these  applications  are  not
discussed herein, but are illustrated in the papers referenced in the
introduction.

AIM-170, CS-289, AD748607,
Yorick Wilks,
"Lakoff on Linguistics and Natural Logic"
Diskfile: LAKOFF.YAW[AIM,DOC]
19 pages, June 1972.

.bi
The paper examines and criticizes Lakoff's notions of a natural logic
and  of  a  generative semantics described in terms of logic, I argue
that  the  relationship  of  these  notions  to  logic  as   normally
understood  is  unclear, but I suggest, in the course of the paper, a
number of  possible  interpretations  of  his  thesis  of  generative
semantics.   I  argue  further  that  on these interpretations a mere
notational variant of Chomskyan theory. I argue, too,  that  Lakoff's
work  may  provide  a  service  in  that it constitutes a <reductio ad
absurdum> of the derivational  paradigm  of  modern  linguistics;  and
shows,  inadvertently,  that  only  a  system  with  the  ability  to
reconsider its own inferences can do the job that Lakoff sets up  for
linguistic   enquirey -- that   is   to   say,  only  an  `artificial
intelligence' system.
.end

*AIM-171, CS-290, AD746147,
Roger Schank,
"Adverbs and Belief"
30 pages, June 1972.

The   treatment   of   a  certain  class  of  adverbs  in  conceptual
representation  is  given.   Certain  adverbs   are   shown   to   be
representative  of complex belief structures.  These adverbs serve as
pointers that explain where the sentence that they modify belongs  in
a belief structure.

*AIM-172, CS-299, AD752801,
Sylvia Weber Russell,
"Semantic Categories of Nominals for Conceptual Dependency Analysis of 
 Natural Language"
64 pages, July 1972.

A system  for  the  semantic  categorization  of  conceptual  objects
(nominals)  is  provided.   The  system  is  intended to aid computer
understanding of  natural  language.   Specific  implementations  for
`noun-pairs' and prepositional phrases are offered.

*AIM-173, CS-305, AD755139,
Gerald Jacob Agin,
"Representation and Description of Curved Objects"
Thesis: Ph.D. in Computer Science,
134 pages, October 1972.

Three dimensional images, similar to depth maps, are obtained with  a
triangulation  system  using  a  television camera, and a deflectable
laser beam diverged into a plane by a cylindrical lens.

Complex  objects  are  represented as structures joining parts called
generalized cylinders.  These primitives are formalized in  a  volume
representation  by  an  arbitrary cross section varying along a space
curve axis.  Several types of joint structures are discussed.

Experimental  results  are  shown  for  the  description (building of
internal computer models) of a handful of complex objects,  beginning
with  laser  range  data  from  actual  objects.   Our  programs have
generated complete  descriptions  of  rings,  cones,  and  snake-like
objects, all of which may be described by a single primitive. Complex
objects, such as dolls, have been segmented into parts, most of which
are well described by programs which implement generalized cylinder
descriptions.

*AIM-174, CS-303, PB212827,
Francis Lockwood Morris,
"Correctness of Translations of Programming Languages -- an Algebraic
 Approach"
Thesis: Ph.D. in Computer Science,
124 pages, August 1972.

Programming languages and their sets of meanings can be  modelled  by
general operator algebras; semantic functions and compiling functions
by  homomorphisms  of  operator  algebras.   A  restricted  class  of
individual  programs, machines, and computations can be modelled in a
uniform manner by binary relational algebras.  A restricted class  of
individual   manner   by   binary  relational  algebras.   These  two
applications of algebra to computing  are  compatible:  the  semantic
function  provided  by interpreting (`running') one binary relational
algebra on another is a homomorphism on  an  operator  algebra  whose
elements are binary relational algebras.

Using these mathematical tools, proofs can be provided systematically
of the correctness of compilers for fragmentary programming languages
each embodying a single language  `feature'.   Exemplary  proofs  are
given   for  statement  sequences,  arithmetic  expressions,  Boolean
expressions, assignment statements, and while  statement.   Moreover,
proofs of this sort can be combined to provide (synthetic) proofs for
in principle, many different  complete  programming  languages.   One
example of such a synthesis is given.

AIM-175, CS-307,,
Hozumi Tanaka,
"Hadamard Transform for Speech Wave Analysis"
Diskfile: HADAM.HT[AIM,DOC],
34 pages, August 1972.

Two methods of speech wave analysis using the Hadamard transform  are
discussed.   The first method is a direct application of the Hadamard
transform for speech waves.   The  reason  this  method  yields  poor
results  is  discussed.   The second method is the application of the
Hadamard transform to a log-magnitude frequency spectrum.  After  the
application  of  the  Fourier  transform  the  Hadamard  transform is
applied to detect a pitch period or to get a smoothed spectrum.  This
method  shows some positive aspects of the Hadamard transform for the
analysis of a speech wave with regard to the reduction of  processing
time required for smoothing, but at the cost of precision.  A formant
tracking program for voiced  speech  is  implemented  by  using  this
method and an edge following technique used in scene analysis.

*AIM-176, CS-308, AD754109,
Jerome A. Feldman, J. R. Low, D. C. Swinehart, R. H. Taylor,
"Recent Developments in SAIL -- an ALGOL based Language for Artificial 
 Intelligence"
22 pages, November 1972.

New features added to SAIL, an ALGOL based languaged for the  PDP-10,
are  discussed.   The features include: procedure variables; multiple
processes; coroutines; a  limited  form  of  backtracking;  an  event
mechanism for inter-process communication; and matching procedures, a
new way of searching the LEAP associative data base.

AIM-177, CS-311,,
Richard Paul,
"Modelling, Trajectory Calculation and Servoing of a Computer Controlled 
 Arm"
Thesis: Ph.D. in Computer Science,
89 pages, November 1972.

The problem of computer contral of an arm is divided into four parts:
modelling, trajectory calculation, servoing and control.

In modelling we  use a symbolic  data structure to  represent objects
in  the  environment.   The program  considers  how the  hand  may be
positioned to grasp these objects and plans how to turn  and position
them  in  order to  make  various  moves. An  arm  model  is used  to
calculate  the configuration-dependent dynamic  properties of the arm
before it is moved.

The arm is  moved along time-coordinated space trajectories  in which
velocity   and  acceleration   are  controlled.     Trajectories  are
calculated for motions  along defined space curves,  as in turning  a
crank;  in such  trajectories  various  joints must  be  free due  to
external motion constraints.

The arm is  servoed by a  small computer.   No analog servo  is used.
The   servo    is   compensated   for   gravity   loading   and   for
configuration-dependent dynamic properties of the arm.

In order to control  the arm, a planning program  interprets symbolic
arm  control  instructions and  generates  a plan  consisting  of arm
motions and hand actions.

The   move  planning   program  has   worked   successfully  in   the
manipulation  of  plane  faced objects.    Complex  motions, such  as
locating  a  bold  and  screwing  a  nut  onto  it,  have  also  been
performed.

*AIM-178, CS-312, AD754108,
Aharon Gill,
"Visual Feedback and Related Problems in Computer Controlled Hand eye
 Coordination"
Thesis:  Ph.D. in Electrical Engineering,
130 pages, October 1972.

A set of programs for precise manipulation of simple  planar  bounded
objects,  by  means  of visual feedback, was developed for use in the
Stanford hand-eye system.  The  system  includes  a  six  degrees  of
freedom  computer  controlled  manipulator (arm and hand) and a fully
instrumented computer television camera.

The  image  of  the  hand  and manipulated objects is acquired by the
computer through the camera.  The stored image is  analyzed  using  a
corner  and  line  finding  program  developed for this purpose.  The
analysis is simplified by using all the information  available  about
the  objects  and  the  hand,  and  previously  measured coordination
errors.   Simple  touch  and  force  sensing  by  the  arm  help  the
determination of three dimensional positions from one view.

The utility of  the information used  to simplify the  scene analysis
depends on  the accuracy of the geometrical  models of the camera and
arm.   A set  of  calibration updating  techniques and  programs  was
developed to  maintain the accuracy  of the camera model  relative to
the arm model.

The precision obtained is better than .1 inch.   It is limited by the
resolution  of the imaging system  and of the  arm position measuring
system.

*AIM-179, CS-320,,
Bruce G. Baumgart,
"Winged Edge Polyhedron Representation"
46 pages, October 1972.

A  winged  edge  polyhedron  representation  is  stated  and a set of
primitives that preserve  Euler's  F-E+V=2  equation  are  explained.
Present  use  of  this  representation in Artificial Intelligence for
computer graphics and world modeling is illustrated and its  intended
future application to computer vision is described.

*AIM-180, CS-321, AD759712,
Ruzena Bajcsy,
"Computer Identification of Textured Visual Scenes"
Thesis:  Ph.D. in Computer Science,
156 pages, October 1972.

This work deals with computer analysis  of  textured  outdoor  scenes
involving grass, trees, water and clouds. Descriptions of texture are
formalized from natural language descriptions; local descriptors  are
obtained  from  the directional and non-directional components of the
Fourier transform power spectrum. Analytic expressions  are  obtained
for  orientation, contrast, size, spacing, and in periodic cases, the
locations of texture elements.  These local descriptors  are  defined
over  windows  of  various  sizes;  the  choice of sizes is made by a
simple higher-level program. 

The  process  of region growing is represented by a sheaf-theoretical
model which formalizes the operation of pasting local structure (over
a  window)  into  global  structure  (over  a  region). Programs were
implemented which form regions of similar color and  similar  texture
with respect to the local descriptors.

An interpretation  is made of  texture gradient as  distance gradient
in space.   A simple world model is  described.  An interpretation of
texture  regions and  texture  gradient  is  made  with  a  simulated
correspondence with the world model.   We find that a problem-solving
approach,  involving hypothesis-verification,  more satisfactory than
an earlier pattern recognition effort (Bajcsy 1970)  and more crucial
to work with  complex scenes than in scenes  of polyhedra.  Geometric
clues from relative sizes,  texture gradients, and interposition  are
important in interpretation.

*AIM-181, CS-325,,
Bruce G. Buchanan,
"Review of Hubert Dreyfus' `What Computers Can't Do': a Critique of 
 Artificial Reason"
14 pages, November 1972.

The recent book "What Computers Can't Do" by  Hubert  Dreyfus  is  an
attack	on  artificial  intelligence research.  This review takes the
position that the philosophical content of the book  is  interesting,
but that the attack on artificial intelligence is not well reasoned.

*AIM-182, CS-326, AD754107,
Kenneth Mark Colby and Franklin Dennis Hilf,
"Can Expert Judges, using Transcripts of Teletyped Psychiatric Interviews,
 Distinguish Human Paranoid Patients from a Computer Simulation of Paranoid
 Processes?"
10 pages, December,1972.

Expert  judges  (psychiatrists  and  computer  scientists)  could not
correctly distinguish a simulation model of paranoid  processes  from
actual paranoid patients.

*AIM-183, CS-344, AD759716,
Roger C. Schank,
"The Fourteen Primitive Actions and their Inferences"
70 pages, March 1973.

In  order  to  represent  the  conceptual  information  underlying  a
natural   language  sentence,   a   conceptual  structure   has  been
established that uses  the basic  actor-action-object framework.   It
was the intent that these structures have only one representation for
one  meaning, regardless of the semantic  form of the  sentence being
represented.   Actions were  reduced to their  basic parts  so as  to
effect  this.  It  was found  that only  fourteen basic  actions were
needed as  building blocks  by which  all verbs  can be  represented.
Each of these  actions has a  set of actions  or states which  can be
inferred when they are present.

*AIM-184, CS-330, AD758651,
Malcolm Newey,
"Axioms and Theorems for Integers, Lists and Finite Sets in LCF"
53 pages, January 1973.

LCF (Logic for  Computable Functions) is  being promoted as  a formal
language  suitable  for the  discussion  of various  problems  in the
Mathematical Theory  of Computation  (MTC).   To this  end,   several
examples of  MTC problems have  been formalised and proofs  have been
exhibited using  the LCF proof-checker.  However,  in these examples,
there has been a certain  amount of ad-hoc-ery in the  proofs; namely
many  mathematical theorems have  been assumed  without proof  and no
axiomatisation of the mathematical domains involved was given.   This
paper describes  a suitable mathematical  environment for  future LCF
experiments  and  its  axiomatic basis.    The  environment developed
deemed appropriate for such experiments, consists of a large  body of
theorems from the areas of  integer arithmetic, list manipulation and
finite set theory.

*AIM-185, CS-333, AD757367,
Ashok K. Chandra, Zohar Manna,
"On the Power of Programming Features"
29 pages, January 1973.

We  consider  the  power of  several  programming  features  such  as
counters,  pushdown stacks,  queues, arrays, recursion  and equality.
In this study program schemas are used as the model  for computation.
The  relations between  the powers  of these  features is  completely
described by a comparison diagram.

*AIM-186, CS-332, AD758645,
Robin Milner,
"Models of LCF"
17 pages, January 1973.

LCF is  a deductive system  for computable  functions proposed by  D.
Scott  in 1969  in an  unpublished  memorandum.   The purpose  of the
present paper  is to  demonstrate the  soundness of  the system  with
respect to  certain models,  which are  partially ordered  domains of
continuous  functions.  This  demonstration was supplied  by Scott in
his memorandum;  the present paper  is merely  intended to make  this
work more accessible.

*AIM-187, CS-331, AD757364,
George E. Collins,
"The Computing Time of the Euclidean Algorithm"
17 pages, January 1973.

The maximum,  minimum and  average computing  times of the  classical
Euclidean algorithm  for the greatest common  divisor of two integers
are derived, to  within codominance, as functions  of the lengths  of
the two inputs and the output.

*AIM-188, CS-336, AD758646,
Ashok K. Chandra,
"On the Properties and Applications of Program Schemas"
Thesis: Ph.D. in Computer Science,
231 pages, March 1973.

The interesting questions  one can ask about program  schemas include
questions about the  `power' of classes of schemas and their decision
problems  viz.  halting  divergence,  equivalence,  etc.    We  first
consider  the powers  of  schemas with  various features:  recursion,
equality tests,  and several data structures such as pushdown stacks,
lists, queues  and arrays.   We then  consider the decision  problems
for  schemas  with  equality  and  with  commutative  and  invertible
functions.  Finally a  generalized class of  schemas is described  in
an  attempt  to  unify  the  various  classes  of  uninterpreted  and
semi-interpreted schemas and schemas with special data structures.

*AIM-189, CS-337, PB218682,
James Gips, George Stiny,
"Aesthetics Systems"
22 pages, January 1973.

The formal  structure of aesthetics  systems is defined.   Aesthetics
systems  provide  for  the  essential  tasks  of  interpretation  and
evaluation  in  aesthetic   analysis.  Kolmogorov's  formulation   of
information theory is  applicable.  An aesthetics system  for a class
of  non-representational, geometric paintings  and its application to
three actual paintings is described in the Appendix.

AIM-190, CS-340, AD759714,
Malcolm Newey,
"Notes on a Problem Involving Permutations as Sequences"
20 pages, March 1973.

.begin turn on "↑[]"
The problem (attributed to R. M. Karp by Knuth ) is
to  describe  the  sequences  of  minimum  length which  contain,  as
subsequences, all  the  permutations of  an  alphabet of  n  symbols.
This paper catalogs some of the  easy observations on the problem and
proves that  the minimum lengths for n=5, n=6 and n=7 are 19, 28, and
39 respectively. Also presented  is a construction which  yields (for
n>2) many appropriate sequences  of length n↑2-2n+4 so giving an upper
bound on length of  minimum strings which  matches exactly all  known
values.
.end

AIM-191, CS-341, AD764272,
Shmuel M. Katz, Zohar Manna,
"A Heuristic Approach to Program Verification"
40 pages, March 1973.

We  present various  heuristic  techniques  for  use in  proving  the
correctness  of computer  programs.  The  techniques are  designed to
obtain automatically the "inductive assertions" attached to the loops
of the program which previously required human "understanding" of the
program's approaches:  one in which we obtain the inductive assertion
by analyzing predicates which are  known to be true at  the entrances
and exits  of the loop (top-down  approach), and another  in which we
generate the inductive assertion directly from the statements of  the
loop (bottom-up approach).

AIM-192, CS-345,,
George E. Collins, Ellis Horowitz,
"The Minimum Root Separation of a Polynomial"
13 pages, April 1973.

The minimum root separation  of a complex polynomial A  is defined as
the  minimum  of the  distances between  distinct  roots of  A.   For
polynomials  with  Gaussian  integer  coefficients  and  no  multiple
roots, three  lower bounds are derived  for the root separation.   In
each  case the bound  is a  function of the  degree, n, of  A and the
sum, d, of the absolute values of the coefficients of  A.  The notion
of a  semi-norm for a  commutative ring is  defined, and it  is shown
how any  semi-norm can  be extended  to polynomial  rings and  matrix
rings, obtaining  a very general  analogue of  Hadamard's determinant
theorem.

AIM-193, CS-346, AD759717,
Kenneth Mark Colby,
"The Rationale for Computer Based Treatment of Language Difficulties
 in Nonspeaking Autistic Children"
Diskfile: AUTISM.KMC[AIM,DOC],
13 pages, March 1973.

The  principles  underlying a  computer-based  treatment  method  for
language acquisition  in nonspeaking autistic children are described.
The main  principle involves  encouragement of  exploratory  learning
with minimum adult interference.

AIM-194, CS-347, PB221170/4,
Kenneth Mark Colby, Franklin Dennis Hilf,
"Multidimensional Analysis in Evaluating a Simulation of Paranoid
 Thought"
10 pages, May 1973.

The  limitations of  Turing's  Test as  an  evaluation procedure  are
reviewed.   More valuable are  tests which ask expert  judges to make
ratings along multiple  dimensions essential to the  model.  In  this
way the  model's weaknesses  become clarified  and the  model builder
learns where the model must be improved.

AIM-195, CS-356, PB222164,
David Canfield Smith, Horace J. Enea,
"MLISP2"
Diskfile: MLISP2.DAV[AIM,DOC],
91 pages, May 1973.

MLISP2 is a high-level programming language based on LISP.
Features:
.bs
1.  The notation of MLISP.

2.  Extensibility -- the ability to extend the language and to define
    new languages.

3.  Pattern matching -- the ability to match input against context free
    or sensitive patterns.

4.  Backtracking -- the ability to set decision points, manipulate 
    contexts and backtrack.
.end

*AIM-196, CS-357, AD762471,
Neil M. Goldman, Christopher K. Riesbeck,
"A Conceptually Based Sentence Paraphraser"
Diskfile:  MARGIE.NMG[AIM,DOC],
88 pages, May 1973.

This report  describes  a system  of programs  which perform  natural
language   processing   based   on   an   underlying  language   free
(conceptual) representation  of  meaning.   This  system is  used  to
produce   sentence   paraphrases   which  demonstrate   a   form   of
understanding  with respect  to a given context.  Particular emphasis
has been placed on  the major subtasks of language  analysis (mapping
natural language into  conceptual structures) and language generation
(mapping conceptual  structures into  natural language),  and on  the
interaction between these processes and a conceptual memory model.

*AIM-197, CS-358, AD762470,
Roger C. Schank, Charles J. Rieger III,
"Inference and the Computer Understanding of Natural Language"
63 pages, May 1973.

The notion of computer understanding of  natural language is examined
relative to inference  mechanisms designed to function in a language-
free deep conceptual  base (Conceptual  Dependency).  The  conceptual
analysis of a  natural language seentence into  this conceptual base,
and  the nature of  the memory  which stores and  operates upon these
conceptual  structures  are  described  from  both   theoretical  and
practical standpoints.  The various types of inferences  which can be
made during  and after  the  conceptual analysis  of a  sentence  are
defined, and  a functioning  program which  performs these  inference
tasks is described.  Actual computer output is included.

AIM-198, CS-364, AD763611,
Ravindra B. Thosar,
"Estimation of Probability Density using Signature Tables for
 Application to Pattern Recognition"
37 pages, May 1973.

Signature table training method consists  of cumulative evaluation of
a   function  (such  as   a  probability   density)  at  pre-assigned
co-ordinate values of  input parameters to the  table.  The  training
is conditional: based on a binary  valued `learning' input to a table
which  is compared  to the  label attached  to each  training sample.
Interpretation of an  unknown sample vector  is then equivalent of  a
table  lookup, i.e. extraction  of the  function value stored  at the
proper co-ordinates.  Such  a technique is very  useful when a  large
number of samples must be interpreted as in  the case of samples must
be  interpreted as  in the  case of speech  recognition and  the time
required for  the trainng  as well  as for  the recognition  is at  a
premium.  However,  this  method  is limited  by  prhibitive  storage
requirements,  even for a  moderate number of  parameters, when their
relative independence  cannot be assumed.   This report  investigates
the  conditions  under   which  the  higher  dimensional  probability
density function can be  decomposed so that  the density estimate  is
obtained  by  a   hierarchy  of  signature  tables   with  consequent
reduction  in  the storage  requirement.   Practical  utility  of the
theoretical results  obtained  in the  report  is demonstrated  by  a
vowel recognition experiment.

AIM-199, CS-398, AD771300,
Bruce G. Baumgart,
"Image Contouring and Comparing"
52 pages, (in preparation).

A  contour  image  representation is  stated  and  an  algorithm  for
converting   a   set   of  digital   television   images   into  this
representation is explained.  The algorithm  consists of five  steps:
digital image thresholding, binary image contouring, polygon nesting,
polygon  smoothing, and polygon comparing.   An implementation of the
algorithm is  the main  routine of  a program  called CRE;  auxiliary
routines provide cart and  turn table control, TV camera input, image
display, and xerox printer output.  A serendip application of CRE  to
type  font construction  is  explained.  Details about  the  intended
application of CRE  to the perception of physical objects will appear
in sequels to this paper.

AIM-200, CS-365,,
Shigeru Igarashi, David C. Luckham, Ralph L. London,
"Automatic Program Verification I:  Logical Basis and its
 Implementation"
50 pages, May 1973.

Defining the semantics  of programming languages by axioms  and rules
of  inference yields a  deduction system  within which proofs  may be
given that  programs satisfy  specifications.   The deduction  system
herein is  shown to  be consistent and  also deductive  complete with
respect  to Hoare's sustem.  A subgoaler  for the deductive system is
described whose  input is  a  significant subset  of Pascal  programs
plus  inductive assertions.    The output  is a  set  of verification
conditions or lemmas  to be proved.   Several non-trivial  arithmetic
and sorting  programs have  been shown  to satisfy specifications  by
using an  interactive theorem prover to automatically generate prrofs
of the  veification  conditions.  Additional components  for  a  more
powerful verficiation system are under construction.

*AIM-201, CS-366, AD763673,
Gunnar Rutger Grape,
"Model Based (Intermediate Level) Computer Vision"
Thesis:  Ph.D. in Computer Science,
256 pages, May 1973.

A  system  for  computer vision  is  presented,  which  is  based  on
two-dimensional  prototypes, and which  uses a  hierarchy of features
for mapping purposes. More  specifically, we are dealing with  scenes
composed of planar faced, convex  objects.  Extensions to the general
planar  faced case are discussed.  The  visual input is provided by a
TV-camera, and the  problem is to  interpret that input by  computer,
as a projection of  a three-dimensional scene.  The digitized picture
is first scanned for significant intensity gradients (called  edges),
which are  likely to  appear at  region- and  object junctions.   The
two-dimensional  scene-representation given  by the totality  of such
intensity discontinuities  (that  word used  somewhat  inexactly)  is
referred to in the sequel  as the `edge-drawing', and constitutes the
input to the vision system presented here.

The   system  proposed  and  demonstrated   in  this  paper  utilizes
perspectively  consistent  two-dimensional  models   (prototypes)  of
views   of   three-dimensional   objects,  and   interpretations   of
scene-representations are  based on  the establish-  ment of  mapping
relationships   from    conglomerates   of   scene-elements    (line-
constellations)  to prototype templates.   The prorotypes are learned
by the program through  analysis of -  and generalization on -  ideal
instances.   The system works  better than any sequential  (or other)
system  presented so far. It should be  well suited to the context of
a complete vision  system using depth, occlusion,  support relations,
etc.   The general case of irregularly  shaped, planar faced objects,
including concave ones, would necessitate such an extended context.

AIM-202, CS-368, AD764396,
Roger C. Schank, Yorick Wilks,
"The Goals of Linguistic Theory Revisited"
44 pages, May 1973.

We examine the  original goals of  generative linguistic theory.   We
suggest  that  these  goals  were  well  defined but  misguided  with
respect to their avoidance the problem of modelling performance.   We
developments  such as  Generative Semantics,  it is  no longer  clear
that  the goals are clearly  defined.  We argue that  it is vital for
linguistics to concern itself with the procedures that  humans use in
language.   We then introduce  a number of  basic human competencies,
in the field of language understanding, understanding in context  and
the use of inferential  information, and argue that the  modelling of
these  aspects  of language  understanding requires  procedures  of a
sort that cannot be easily accomodated within the  dominant paradigm.
In particular, we argue that the  procedures that will be required in
these  cases  ought  to be  linguistic,  and  that  the simple-minded
importation of techniques, and that the  simple-minded importation of
techniques from logic may  create a linguistics in which there cannot
be procedures of the required sort.

AIM-203, CS-369, AD764274,
Roger C. Schank,
"The Development of Conceptual Structures in Children"
31 pages, May 1973.

Previous papers by the  author have hypothesized that is  is possible
to  represent  the  meaning of  natural  language  sentences using  a
framework  which has  only  fourteen  primitive  ACTs.    This  paper
addresses the problem of when and  how these ACTs might be learned by
children.   The speech of  a child of age 2  is examined for possible
knowledge of the primitive  ACTs as well as the  conceptual relations
underlying language.   It  is shown that  there is evidence  that the
conceptual structures underlying  language are  probably complete  by
age 2.  Next a  child is studied from birth to age l.   The emergence
of  the primitive ACTs and  the conceptual relations is  traced.  The
hypothesis  is  made  that  the  structures  that  underlie  and  are
necessary for language are present by age l.

AIM-204, CS-373, AD765353,
Kurt VanLehn,
"SAIL Users Manual"
Diskfile:  SAIL.KVL[AIM,DOC],
122 pages, July 1973.

SAIL is  a high-level programming  language for the  PDP-10 computer.
It  includes an  extended ALGOL  60 compiler and  a companion  set of
execution-time  routines.    In  addition  to  ALGOL,   the  language
features:  (1)  flexible  linking   to  hand-coded  machine  language
algorithms,  (2) complete access to the  PDP-10 I/O facilities, (3) a
complete system  of compile-time arithmetic  and logic  as well as  a
flexible  macro  system  (4)  user  modifiable  error  handling,  (5)
backtracking, and (6)  interrupt facilities.   Furthermore, a  subset
of the SAIL language,  called LEAP, provides facilities for  (1) sets
and  lists,  (2)  an  associative  data  structure,  (3)  independent
processes, and (4) procedure variables.   The LEAP subset of SAIL  is
an extension of  the LEAP language, which was designed  by J. Feldman
and  P. Rovner,  and  implemented on  Lincoln Laboratory's  TX-2 (see
[Feldman & Rovner]).  The extensions to LEAP  are partially described
in `Recent Developments in SAIL' (see [Feldman]).

This  manual  describes  the  SAIL  language and  the  execution-time
routines for  the typical  SAIL user:  a non-novice  programmer  with
some knowledge of ALGOL.  It lies  somewhere between being a tutorial
and a reference manual.

AIM-205, CS-370, AD764288,
N. S. Sridharan, et al,
"A Heuristic Program to Discover Syntheses for Complex Organic
 Molecules"
30 pages, June 1973.

Organic Chemical  Synthesis is  found to  be a  suitable program  for
developing  machine  intelligence.   A previous  paper  described the
objective and  global characteristics of  the project.   The  present
article  aims to  describe the  program organization  as a  heuristic
search,  the  design  of  the Problem  Solving  Tree  and  the search
procedures in considerable detail.  Examples  of syntheses discovered
and the problem  solving tree developed are given.   The programs are
written mostly in PL1(F) applicable to an IBM 360/67 and the  timings
(batch  mode) indicate  that  we have  fast  and efficient  practical
systems.

AIM-206, CS-377, AD764652,
Yorick Wilks,
"Preference Semantics"
20 pages, July 1973.

Preference  semantics  [PS]  is  a  set   of  formal  procedures  for
representing the  meaning structure of natural  language, with a view
to embodying  that structure  within a  system that  can  be said  to
understand, rather  than within what  I would call  the `derivational
paradigm',  of transformational grammar [TG] and generative semantics
[GS], which seeks to determine the well-formedness,  or otherwise, of
sentences. 

I outline a  system of preference semantics that  does this: for each
phrase or  clause of  a  complex sentence,  the  system builds  up  a
network of  lexical trees  with the  aid of  structured items  called
templates and,  at the next level, it  structures those networks with
higher level  items  called  paraplates  and  common-sense  inference
rules.  At  each stage the system directs itself  towards the correct
network  by always  opting for the  most `semantically  dense' one it
can  construct.   I  suggest  that  this  opting  for  the  `greatest
semantic  density'  can  be   seen  as  an  interpretation  of  Joos'
`Semantic Axiom Number 1'.

I argue that the analysis of  quite simple examples requires the  use
of inductive rules  of inference which cannot,  theoretically cannot,
be  accomodated within  the derivational paradigm.   I  contrast this
derivational paradigm  of  language processing  with  the  artificial
intelligence [AI] paradigm.

AIM-207, CS-378, AD767333,
James Anderson Moorer,
"The `Optimum-comb' Method of Pitch Period Analysis in Speech"
25 pages, June 1967.

A new method  of tracking the  fundamental frequency of voiced speech
is  descirbed. The method is  shown to be of  similar accuracy as the
Cepstrum technique.   Since  the method  involves  only addition,  no
multiplication, it is shown to be faster than the SIFT algorithm.

AIM-208, CS-379, AD767334,
James Anderson Moorer,
"The Heterodyne Method of Analysis of Transient Waveforms"
25 pages, June 1973.

A  method of  analysis  of transient  waveforms  is discussed.    Its
properties  and limitations are  presented in the  context of musical
tones.  The method  is shown to be useful  when the risetimes of  the
partials of the  tone are not too short.   An extention to inharmonic
partials and polyphonic musical sound is discussed.

AIM-209, CS-380, AD767695,
Yoram Yakimovsky,
"Scene Analysis using a Semantic Base for Region Growing"
Thesis:  Ph.D. in Computer Science,
120 pages, July 1973.

The  problem  of  breaking  an  image   into  meaningful  regions  is
considered.     A   probabilistic   semantic  basis   is  effectively
integrated with the segmentation process, providing various  decision
criteria.     Learning   facilities  are   provided  for   generating
interactively  the probabilistic  bases.  A  programming system which
is  based on  these  ideas  and  its successful  application  to  two
problem domains are described.

AIM-210, CS-382, AD767335,
Zohar Manna, Amir Pnueli,
"Axiomatic Approach to Total Correctness of Programs"
25 pages, July 1973.

We present here an axiomatic approach which enables one to prove by
formal methods that his program is `totally correct' (i.e., it 
terminates and is logically correct -- does what it is supposed to
do).  The approach is similar to Hoare's approach for proving that
a program is `partially correct' (i.e., that whenever it terminates
it produces correct results).  Our extension to Hoare's method lies in
the possibility of proving correctness and termination at once, and 
in the enlarged scope of properties that can be proved by it.

.end "aimac"
.back