Milestones in Discovery and Invention h A I RTIFICIAL NTELLIGENCE MIRRORS FOR THE MIND Harry Henderson To the researchers, the visionaries, and the critics. ARTIFICIAL INTELLIGENCE: Mirrors for the Mind Copyright © 2007 by Harry Henderson All rights reserved. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval systems, without permission in writing from the publisher. For information contact: Chelsea House An imprint of Infobase Publishing 132 West 31st Street New York NY 10001 ISBN-10: 0-8160-5749-4 ISBN-13: 978-0-8160-5749-8 Library of Congress Cataloging-in-Publication Data Henderson, Harry. Artificial intelligence : mirrors for the mind / Harry Henderson. p. cm. — (Milestones in discovery and invention) Includes bibliographical references and index. ISBN 0-8160-5749-4 1. Artificial intelligence. I. Title. II. Series. Q335.H455 2007 006.3.—dc22 2006016639 Chelsea House books are available at special discounts when purchased in bulk quantities for businesses, associations, institutions, or sales promotions. Please call our Special Sales Department in New York at (212) 967-8800 or (800) 322-8755. You can find Chelsea House on the World Wide Web at http://www.chelseahouse.com Text design by James Scotto-Lavino Cover design by Dorothy M. Preston Illustrations by Sholto Ainslie and Melissa Ericksen Printed in the United States of America MP FOF 10 9 8 7 6 5 4 3 2 1 This book is printed on acid-free paper. e CONTENTS PREFACE ix ACKNOWLEDGMENTS xiii INTRODUCTION xv 1 BEYOND CALCULATION: ALAN TURING AND THE BIRTH OF ARTIFICIAL INTELLIGENCE 1 Science and Friendship 1 Does It Compute? 3 From Symbols to Codes 4 Riddling the Enigma 5 Designing Electronic Computers 8 Toward AI 9 The “Turing Test” 10 Turing and Objections to AI 12 Issues: Is the Turing Test a Dead End? 14 The Final Enigma 15 Chronology 16 Further Reading 17 2 MIND IN A BOX: ALLEN NEWELL AND HERBERT SIMON EXPLORE REASONING AND DECISION MAKING 19 A Vigorous Mind 20 Looking for Interesting Problems 21 Simulating Organizations 22 Meeting of the Minds 22 Simon Sets His Course 23 Simon and Newell’s Opening Moves 25 I Was There: Unexpected Results 28 A Logic Machine 28 The General Problem Solver 30 Parallels: Chess and Mathematical Proofs 32 I Was There: The Birth of AI 33 Expanding the Artificial Mind 34 A General Theory of Thinking 34 Getting to “Good Enough” 35 A Rich Legacy 36 Chronology 37 Further Reading 38 3 I HAVE A LITTLE LIST: JOHN MCCARTHY CREATES TOOLS FOR AI 41 Radical Roots 41 A Possible Machine 42 Dartmouth and the “Birth” of AI 43 Lisp 45 Framing the Question 47 Connections: SHRDLU and the “Blocks World” 48 Reflections and Rewards 51 McCarthy on the Future of AI 52 Chronology 54 Further Reading 55 4 SIMULATED BRAINS: MARVIN MINSKY’S JOURNEY FROM NEURAL NETWORKS TO MULTIPLE MINDS 56 Experiencing Science at Harvard 57 Hunting the SNARC 58 Perceptrons and Neural Networks 59 Emergence of AI Research 60 Steps toward AI 60 Other Scientists: Seymour Papert (1928– ) 61 Solving Problems: Basic AI Strategies 62 Frames to Organize Knowledge 63 Many Minds 65 Still Going Strong 66 Solving Problems: Improving or Copying the Brain? 67 The Emotion Machine 68 Issues: Minsky on AI Research and the Nature of Consciousness 69 Chronology 71 Further Reading 72 5 HARNESSING KNOWLEDGE: EDWARD FEIGENBAUM AND EXPERT SYSTEMS 74 A “Practical” Career 75 Meeting the “Thinking Machine” 76 From Deduction to Induction 76 An Automated Chemist 78 The Priority of Knowledge 79 Building an Expert System 80 The “Expert Company” 82 Connections: Prolog, the Logic Programming Language 83 Issues: The “AI Winter” 84 What Comes Next? 84 Parallels: Japan’s “Fifth Generation” 87 Chronology 88 Further Reading 88 6 THE COMMONSENSE COMPUTER: DOUGLAS LENAT AND THE CYC PROJECT 90 Saved by Science 91 A Commonsense Approach 92 The Automated Mathematician 93 The Need for Knowledge 94 Cyc: An Encyclopedia for Machines 95 Building Cyc 96 Using Cyc 98 Achievements and Criticisms 100 Connections: More Uses for Cyc 100 Chronology 103 Further Reading 104 7 AT YOUR SERVICE: PATTIE MAES AND THE NEW BREED OF INTELLIGENT AGENTS 105 A New Kind of Program 106 Solving Problems: How Agent Programs Work 108 Commercial Applications 110 Future Agents 110 Turning “Things” into Agents? 111 “What Would They Think?” 112 Other Scientists: Stacy Marsella, David Pynadath, and PsychSim 113 Visionary and “Download Diva” 114 Social Impact: Can Software Agents Be Harmful? 115 Chronology 116 Further Reading 116 8 ANSWERING ELIZA: JOSEPH WEIZENBAUM AND THE SOCIAL RESPONSIBILITY OF AI 118 Working with Computers 118 Ask ELIZA 119 I Was There: Passing the Turing Test? 122 Becoming a Critic of Computers 124 A Social Critique 125 Trends: “Chatterbots” 126 Against Oppressive Technology 127 Later Years 130 Chronology 131 Further Reading 132 9 A PHILOSOPHER’S CHALLENGE: HUBERT DREYFUS AND THE ASSUMPTIONS OF AI 134 The Philosopher and the Robots 136 Against the “Alchemists” 137 The AI Community Responds 139 “What Computers Can’t Do” 139 Connections: What about the “Other” AI? 140 Taking On the Internet 141 Issues: Differing Views of Computers and Humans 142 Chronology 144 Further Reading 144 10 WHEN EVERYTHING CHANGES: RAY KURZWEIL AND THE TECHNOLOGICAL SINGULARITY 146 “I Have Got a Secret” 146 Learning about AI 147 The Reading Machine 148 The Universal Instrument 149 I Was There: The Old Engineer’s Trick 150 Trends: Kurzweil’s Predictions for 2009 152 From Entrepreneur to Visionary 154 The “Technological Singularity” 155 Other Writers: David Brin (1950– ) 156 “Live Long Enough to Live Forever” 159 Issues: Kurzweil and the AI Critics 160 Chronology 161 Further Reading 162 CHRONOLOGY 165 GLOSSARY 170 FURTHER RESOURCES 177 INDEX 183 e PREFACE The Milestones in Discovery and Invention set is based on a simple but powerful idea—that science and technology are not separate from people’s daily lives. Rather, they are part of seeking to understand and reshape the world, an activity that virtually defines being human. More than a million years ago, the ancestors of modern humans began to shape stones into tools that helped them compete with the specialized predators around them. Starting about 35,000 years ago, the modern type of human, Homo sapiens, also created elabo- rate cave paintings and finely crafted art objects, showing that tech- nology had been joined with imagination and language to compose a new and vibrant world of culture. Humans were not only shaping their world but representing it in art and thinking about its nature and meaning. Technology is a basic part of that culture. The mythologies of many peoples include a trickster figure, who upsets the settled order of things and brings forth new creative and destructive pos- sibilities. In many myths, for instance, a trickster such as the Native Americans’ Coyote or Raven steals fire from the gods and gives it to human beings. All technology, whether it harnesses fire, electric- ity, or the energy locked in the heart of atoms or genes, partakes of the double-edged gift of the trickster, providing power to both hurt and heal. An inventor of technology is often inspired by the discoveries of scientists. Science as we know it today is younger than technology, dating back about 500 years to a period called the Renaissance. During the Renaissance, artists and thinkers began to explore nature systematically, and the first modern scientists, such as Leonardo da Vinci (1452–1519) and Galileo Galilei (1564–1642), ix