Table Of Content

U nderstanding Computers and Cognition A New Foundation forDesign TERRY WINOGRAD FERNANDO FLORES A 77 Addison-Wesley Publishing Company, Inc. Reading, Massachusetts Menlo Park, California New York Don Mills, Ontario Wokingharn, England Amsterdam Bonn Sydney Singapore Tokyo Madrid San Juan Contents Preface xi Acknowledgments xiii PART I - Theoretical Background 1 Introduction 3 1.1 The question of design 4 1.2 The role of tradition 7 1.3 Our path 8 2 The rationalistic tradition 14 2. 1 The rationalistic orientation . 14 2.2 Language, truth, and the world ,. 17 2,3 Decision making and problem solving 20 2.4 Cognitive science 23 3 Understanding and Being 27 3.1 Hermeneutics 27 3.2 Understanding and ontology . „ 30 3.3 An illustration of thrownness 33 3.4 Breaking down and readiness-to-hand 36 4 Cognition as a biological phenomenon 38 4.1 The closure of the nervous system 41 4.2 Autopoiesis, evolution, and learning 44 4.3 The cognitive domain „ 46 4.4 Consensual domains 48 4.5 The observer and description 50 4.6 Domains of explanation ,. „ 52 v vi CONTENTS 5 Language, listening, and commitment 54 5..1 Listening in a background ., 54 5.2 Meaning, commitment, and speech acts 58 5.3 Objectivity and tradition 60 5.4 Recurrence and formalization 64 5.5 Breakdown, language, and existence 68 6 Towards a new orientation 70 6.1 Cognition and being in the world . 70 6..2 Knowledge and representation . ,. ,. ,. 72 6..3 Pre-understanding and background . 74 6.4 Language and action 76 6.5 Breakdown and the ontology of design 77 PART II - Computation, Thought, and Language 7 Computers and representation 83 7.1 Programming as representation 84 7.2 Levels of representation 86 7.3 Can computers do more than you tell them to do? ,. 90 8 Computation and intelligence 93 8.1 Why do we ask? 93 8,2 Intelligence as rational problem solving 95 8.3 The phenomenon of blindness ,. 97 8.4 What about learning and evolution? ,.,. 100 8.5 Can pigs have wings? 104 9 Understanding language 107 9..1 Artificial intelligence and language understanding . 107 9.2 The problem of background .. 111 9.3 Understanding as pattern recognition 115 9.4 What does it mean to understand? . „ 119 10 Current directions in artificial intelligence 125 10.1 The forking of the paths . ,. 126 10.2 Expert systems 131 10.3 The fifth generation computer system 133 CONTENTS Vii PART III - Design 11 Management and conversation 143 11.1 Management and decision making 144 11.2 Decision making and resolution . ,. 147 11,3 Organizations as networks of commitments 150 11.4 Decision support systems 152 11,5 Tools for conversation 157 12 Using computers: A direction for design 163 12.1 A background for computer design 164 12.2 A design example . 167 12,3 Systematic domains 174 12,4 Technology and transformation 177 Bibliography 181 Name Index 191 Subject Index 194 For the people of Chile Preface This is a book about the design of computer technology. In it, we look closely at computers as they exist today and we set out new directions for future development.. The discourse presented here, however, is not what one would expect to find in a book of science and engineering. It moves among topics and purposes that appear to be worlds apart: it is both theoretical and practical; it is concerned with computer technology and with the nature of human existence; with the philosophy of language and with office automation. But it is more than a study in contrasts. Our intention in bringing together these diverse elements is to generate understanding-to let the apparent chasms become spaces in which new possibilities are revealed. All new technologies develop within the background of a tacit under standing of human nature and human work. The use of technology in turn leads to fundamental changes in what we do, and ultimately in what it is to be human. We encounter the deep questions of design when we recognize that in designing tools we are designing ways of being. By confronting these questions directly, we can develop a new background for understand ing computer technology-one that can lead to important advances in the design and use of computer systems. When we began the collaboration that led to this book, we had no idea where our discussions would lead. We had lived through very different ex- periences; we spoke different languages (both literally and metaphorically); and we had studied in disparate fields, Terry Winograd has been actively engaged for many years in computer science and artificial intelligence research at the Massachusetts Institute of Technology, Stanford University, and the Xerox Palo Alto Research Center.. His work has consisted primarily of designing systems (both formal languages and computer programs) for the representation and analysis of language and knowledge. Fernando Flores has had experience with social and political organization at the highest level of government, in his posts as director of the state-owned corporations, Minister of Economics, and Minister of Finance in the government of Salvador Allende in Chile between 1970 and 1973. He was xi xii PREFACE instrumental in a large-scale project to apply cybernetic theory to practical management problems (see Beer, Platform for Change, 1975) and is primarily interested in the understanding of social reality that we can gain through combining theory and practice. In spite of these differences, we had a sense that we shared much in our understanding of the world, and we entered into a dialog to explore this common ground. The dialog evolved into a paper, the paper in turn expanded and became a book, and the book evolved through a series of drafts whose focus shifted dramatically.. In our reading and discussions, we came to the realization that although our formal training was in the technical fields of mathematics and computer science, many of our guiding intuitions about language and thought were not compatible with the traditions in those disciplines, We found ourselves in much closer accord with writers who were far removed from the mathematico-logical paradigm, who identified their interests as bio- logy, hermeneutics, and phenomenology. One of the initial attractions of this work was the understanding it provided of the larger human context in which the study of cognition has meaning. What surprised us was that the ideas were so relevant to the practical work in which we are engaged: the design of computer systems and the management of complex organizations. The philosophical ideas of thinkers such as Heidegger, Gadamer, Maturana, and Austin provided a framework to integrate what we had previously learned through our practical experience. As we studied further, we began to formulate new theoretical founda tions for the design of computer technologies. In working to clarify the nature and role of computers we were forced to reject many assumptions that we had long accepted implicitly and that go unquestioned in most discussions of computing. We had to address new questions, and these in turn led to looking more carefully at what people actually do with computers, and what might be done better. Readers with a background in science and technology may find it im- plausible that philosophical considerations have practical relevance for their work. Philosophy may be an amusing diversion, but it seems that the theories relevant to technological development are those of the hard sciences and engineering. We have found quite the opposite,. Theories about the nature of biological existence, about language, and about the nature of human action have a profound influence on the shape of what we build and how we use it. We have accordingly devoted a considerable amount of space, especially in the first part of the book, to discussing matters that appear unrelated to computers but that are nonetheless in- dispensable in the process of opening up for the reader new possibilities and new directions for what we can do with them. In the course of developing a new understanding we came across questions that have long been the subject of debate, such as "Can computers