Foundational Issues in Artificial Intelligence and Cognitive Science:
Impasse and Solution.
Elsevier Science
1995
Mark H. Bickhard
Lehigh University
mhb0@lehigh.edu
Loren Terveen
AT&T Bell Laboratories
terveen@research.att.com
Now in paperback!
The book focuses on a conceptual flaw in contemporary artificial intelligence and cognitive science. Many people have discovered diverse manifestations and facets of this flaw, but the central conceptual impasse is at best only partially perceived. Its consequences, nevertheless, visit themselves as distortions and failures of multiple research projects -- and make impossible the ultimate aspirations of the fields.
The impasse concerns a presupposition concerning the nature of representation -- that all representation has the nature of encodings: encodingism. Encodings certainly exist, but encodingism is at root logically incoherent; any programmatic research predicated on it is doomed to distortion and ultimate failure.
The impasse and its consequences -- and steps away from that impasse -- are explored in a large number of projects and approaches. These include SOAR, CYC, PDP, situated cognition, subsumption architecture robotics, and the frame problems -- a general survey of the current research in AI and Cognitive Science emerges.
Interactivism, an alternative model of representation, is proposed and examined.
The central point of Foundational Issues in Artificial Intellligence and Cognitive Science -- Impasse and Solution is that there is a conceptual flaw in contemporary approaches to artificial intelligence and cognitive science, a flaw that makes impossible the ultimate aspirations of these fields. Many people have discovered diverse manifestations and facets of this flaw, but the central conceptual impasse is only partially perceived. The consequences, nevertheless, visit themselves as distortions and failures of research projects across the fields.
The locus of the impasse concerns a common assumption or presupposition that underlies all parts of the field -- a presupposition concerning the nature of representation. We call this assumption "encodingism", the assumption that representation is fundamentally constituted as encodings. This assumption, in fact, has been dominant throughout Western history. We argue that it is at root logically incoherent, and, therefore, that any programmatic research predicated on it is doomed to distortion and ultimate failure.
On the other hand, encodings clearly do exist, and therefore are clearly possible, and we show how that could be -- but they cannot be the foundational form of representation. Similarly, contemporary encoding approaches are enormously powerful, and major advances have been made within these dominant programmatic frameworks -- but the encodingism flaw in those frameworks limit their ultimate possibilities, and will frustrate efforts toward the programmatic goal of understanding and constructing minds.
The book characterizes and demonstrates this impasse, discusses a number of partial recognitions of and movements away from it, and then traces its consequences in a large number of projects and approaches within the fields. These include SOAR, CYC, PDP, situated cognition, subsumption architecture robotics, and the frame problems. In surveying the consequences of the impasse, we also provide a general survey of the current research in AI and Cognitive Science per se.
We do not propose an unsolvable impasse, and, in fact, present an alternative that does resolve that impasse. This is developed for contrast, for perspective, to demonstrate that there is an alternative, and to explore some of its nature. We end with an exploration of some of the architectural implications of the alternative -- called interactivism -- and argue that such architectures are 1) not subject to the encodingism incoherence 2) more powerful than Turing machines, 3) more consistent with properties of central nervous system functioning than other contemporary approaches, and 4) capable of resolving the many problematics in the field that we argue are in fact manifestations of the underlying impasse.
The audience for this book will include researchers, academics, and students in artificial intelligence, cognitive science, robotics, cognitive psychology, philosophy of mind and language, natural language processing, connectionism, and learning. The focus of the book is on the nature of representation, and representation permeates everywhere -- so also, therefore, do the implications of our critique and our alternative permeate everywhere.
Mark H. Bickhard
Lehigh University
Loren Terveen
AT&T Bell Laboratories
1995
Elsevier Science Publishers
Preface xi
Introduction 1
A PREVIEW 2
I GENERAL CRITIQUE 5
1 Programmatic Arguments 7
CRITIQUES AND QUALIFICATIONS 8
DIAGNOSES AND SOLUTIONS 8
IN-PRINCIPLE ARGUMENTS 9
2 The Problem of Representation 11
ENCODINGISM 11
Circularity 12
Incoherence - The Fundamental Flaw 13
A First Rejoinder 15
The Necessity of an Interpreter 17
3 Consequences of Encodingism 19
LOGICAL CONSEQUENCES 19
Skepticism 19
Idealism 20
Circular Microgenesis 20
Incoherence Again 20
Emergence 21
4 Responses to the Problems of Encodings 25
FALSE SOLUTIONS 25
Innatism 25
Methodological Solipsism 26
Direct Reference 27
External Observer Semantics 27
Internal Observer Semantics 28
Observer Idealism 29
Simulation Observer Idealism 30
SEDUCTIONS 31
Transduction 31
Correspondence as Encoding:
Confusing Factual and Epistemic Correspondence 32
5 Current Criticisms of AI and Cognitive Science 35
AN APORIA 35
Empty Symbols 35
ENCOUNTERS WITH THE ISSUES 36
Searle 36
Gibson 40
Piaget 40
Maturana and Varela 42
Dreyfus 42
Hermeneutics 44
6 General Consequences of the Encodingism Impasse 47
REPRESENTATION 47
LEARNING 47
THE MENTAL 51
WHY ENCODINGISM? 51
II INTERACTIVISM:
AN ALTERNATIVE TO ENCODINGISM 53
7 The Interactive Model 55
BASIC EPISTEMOLOGY 56
Representation as Function 56
Epistemic Contact: Interactive Differentiation and Implicit Definition 60
Representational Content 61
EVOLUTIONARY FOUNDATIONS 65
SOME COGNITIVE PHENOMENA 66
Perception 66
Learning 69
Language 71
8 Implications for Foundational Mathematics 75
TARSKI 75
Encodings for Variables and Quantifiers 75
Tarski's Theorems and the Encodingism Incoherence 76
Representational Systems Adequate to Their Own Semantics 77
Observer Semantics 78
Truth as a Counterexample to Encodingism 79
TURING 80
Semantics for the Turing Machine Tape 81
Sequence, But Not Timing 81
Is Timing Relevant to Cognition? 83
Transcending Turing Machines 84
III ENCODINGISM:
ASSUMPTIONS AND CONSEQUENCES 87
9 Representation: Issues within Encodingism 89
EXPLICIT ENCODINGISM IN THEORY AND PRACTICE 90
Physical Symbol Systems 90
The Problem Space Hypothesis 98
SOAR 100
PROLIFERATION OF BASIC ENCODINGS 106
CYC - Lenat's Encyclopedia Project 107
TRUTH-VALUED VERSUS NON-TRUTH-VALUED 118
Procedural vs Declarative Representation 119
PROCEDURAL SEMANTICS 120
Still Just Input Correspondences 121
SITUATED AUTOMATA THEORY 123
NON-COGNITIVE FUNCTIONAL ANALYSIS 126
The Observer Perspective Again 128
BRIAN SMITH 130
Correspondence 131
Participation 131
No Interaction 132
Correspondence is the Wrong Category 133
ADRIAN CUSSINS 134
INTERNAL TROUBLES 136
Too Many Correspondences 137
Disjunctions 138
Wide and Narrow 140
Red Herrings 142
10 Representation: Issues about Encodingism 145
SOME EXPLORATIONS OF THE LITERATURE 145
Stevan Harnad 145
Radu Bogdan 164
Bill Clancey 169
A General Note on Situated Cognition 174
Rodney Brooks: Anti-Representationalist Robotics 175
Agre and Chapman 178
Benny Shanon 185
Pragmatism 191
Kuipers' Critters 195
Dynamic Systems Approaches 199
A DIAGNOSIS OF THE FRAME PROBLEMS 214
Some Interactivism-Encodingism Differences 215
Implicit versus Explicit Classes of Input Strings 217
Practical Implicitness: History and Context 220
Practical Implicitness: Differentiation and Apperception 221
Practical Implicitness: Apperceptive Context Sensitivities 222
A Counterargument: The Power of Logic 223
Incoherence: Still another corollary 229
Counterfactual Frame Problems 230
The Intra-object Frame Problem 232
11 Language 235
INTERACTIVIST VIEW OF COMMUNICATION 237
THEMES EMERGING FROM AI RESEARCH IN LANGUAGE 239
Awareness of the Context-dependency of Language 240
Awareness of the Relational Distributivity of Meaning 240
Awareness of Process in Meaning 242
Toward a Goal-directed, Social Conception of Language 247
Awareness of Goal-directedness of Language 248
Awareness of Social, Interactive Nature of Language 252
Conclusions 259
12 Learning 261
RESTRICTION TO A COMBINATORIC SPACE OF ENCODING 261
LEARNING FORCES INTERACTIVISM 262
Passive Systems 262
Skepticism, Disjunction, and the Necessity of Error for Learning 266
Interactive Internal Error Conditions 267
What Could be in Error? 270
Error as Failure of Interactive Functional Indications -
of Interactive Implicit Predications 270
Learning Forces Interactivism 271
Learning and Interactivism 272
COMPUTATIONAL LEARNING THEORY 273
INDUCTION 274
GENETIC AI 275
Overview 276
Convergences 278
Differences 278
Constructivism 281
13 Connectionism 283
OVERVIEW 283
STRENGTHS 286
WEAKNESSES 289
ENCODINGISM 292
CRITIQUING CONNECTIONISM AND
AI LANGUAGE APPROACHES 296
IV SOME NOVEL ARCHITECTURES 299
14 Interactivism and Connectionism 301
INTERACTIVISM AS AN INTEGRATING PERSPECTIVE 301
Hybrid Insufficiency 303
SOME INTERACTIVIST EXTENSIONS OF ARCHITECTURE 304
Distributivity 304
Metanets 307
15 Foundations of an Interactivist Architecture 309
THE CENTRAL NERVOUS SYSTEM 310
Oscillations and Modulations 310
Chemical Processing and Communication 311
Modulatory "Computations" 312
The Irrelevance of Standard Architectures 313
A Summary of the Argument 314
PROPERTIES AND POTENTIALITIES 317
Oscillatory Dynamic Spaces 317
Binding 318
Dynamic Trajectories 320
"Formal" Processes Recovered 322
Differentiators In An Oscillatory Dynamics 322
An Alternative Mathematics 323
The Interactive Alternative 323
V CONCLUSIONS 325
16 Transcending the Impasse 327
FAILURES OF ENCODINGISM 327
INTERACTIVISM 329
SOLUTIONS AND RESOURCES 330
TRANSCENDING THE IMPASSE 331
References 333
Index 367
Artificial Intelligence and Cognitive Science are at a foundational impasse which is at best only partially recognized. This impasse has to do with assumptions concerning the nature of representation: standard approaches to representation are at root circular and incoherent. In particular, Artificial Intelligence research and Cognitive Science are conceptualized within a framework that assumes that cognitive processes can be modeled in terms of manipulations of encoded symbols. Furthermore, the more recent developments of connectionism and Parallel Distributed Processing, even though the issue of manipulation is contentious, share the basic assumption concerning the encoding nature of representation. In all varieties of these approaches, representation is construed as some form of encoding correspondence. The presupposition that representation is constituted as encodings, while innocuous for some applied Artificial Intelligence research, is fatal for the further reaching programmatic aspirations of both Artificial Intelligence and Cognitive Science.
First, this encodingist assumption constitutes a presupposition about a basic aspect of mental phenomena -- representation -- rather than constituting a model of that phenomenon. Aspirations of Artificial Intelligence and Cognitive Science to provide any foundational account of representation are thus doomed to circularity: the encodingist approach presupposes what it purports to be (programmatically) able to explain. Second, the encoding assumption is not only itself in need of explication and modeling, but, even more critically, the standard presupposition that representation is essentially constituted as encodings is logically fatally flawed. This flaw yields numerous subsidiary consequences, both conceptual and applied.
This book began as an article attempting to lay out this basic critique at the programmatic level. Terveen suggested that it would be more powerful to supplement the general critique with explorations of actual projects and positions in the fields, showing how the foundational flaws visit themselves upon the efforts of researchers. We began that task, and, among other things, discovered that there is no natural closure to it -- there are always more positions that could be considered, and they increase in number exponentially with time. There is no intent and no need, however, for our survey to be exhaustive. It is primarily illustrative and demonstrative of the problems that emerge from the underlying programmatic flaw. Our selections of what to include in the survey have had roughly three criteria. We favored: 1) major and well known work, 2) positions that illustrate interesting deleterious consequences of the encodingism framework, and 3) positions that illustrate the existence and power of moves in the direction of the alternative framework that we propose. We have ended up, en passant, with a representative survey of much of the field. Nevertheless, there remain many more positions and research projects that we would like to have been able to address.
The book has gestated and grown over several years. Thanks are due to many people who have contributed to its development, with multitudinous comments, criticisms, discussions, and suggestions on both the manuscript and the ideas behind it. These include, Gordon Bearn, Lesley Bickhard, Don Campbell, Robert Campbell, Bill Clancey, Bob Cooper, Eric Dietrich, Carol Feldman, Ken Ford, Charles Guignon, Cliff Hooker, Norm Melchert, Benny Shanon, Peter Slezak, and Tim Smithers. Deepest thanks are also due to the Henry R. Luce Foundation for support to Mark Bickhard during the final years of this project.
Mark H. Bickhard
Henry R. Luce Professor of
Cognitive Robotics & the Philosophy of Knowledge
Department of Psychology
17 Memorial Drive East
Lehigh University
Bethlehem, PA 18015
mhb0@lehigh.edu
Loren Terveen
Human Computer Interface Research
AT&T Bell Laboratories
600 Mountain Avenue
Murray Hill, NJ 07974
terveen@research.att.com
Identifies a fundamental premise about the nature of representation that underlies much of Cognitive Science -- that representation is constituted as encodings.
Explores fatal flaws with this premise.
Surveys major projects within Cognitive Science and Artificial Intelligence.
Shows how they embody the encodingism premise, and how they are limited by it.
Identifies movements within Cognitive Science and AI away from encodingism.
Presents an alternative to encodingism -- interactivism.
Demonstrates that interactivism avoids the fatal flaws of encodingisms, and that it provides a coherent framework for understanding representation.
Unifies insights from the various movements in Cognitive Science away from encodingism.
Sketches an interactivist cognitive architecture.
Cognitive Science
Simulation of Cognitive Processes
Artificial Intelligence, Knowledge Engineering, Expert Systems
Human Information Processing
Philosophy of Language
Philosophy of Mind
Cognitive Psychology
Robotics
Artificial Life
Autonomous Agents
Dynamic Systems and Behavior
Learning
Theory of Computation
Semantics
Pragmatics
Connectionism
Linguistics
Neuroscience
396 pages
Paperback:
ISBN 0 444 82520 7
US $97.00
Hardback:
ISBN 0 444 82048 5
US $150.00
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