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Understanding computers and cognition: A new foundation for design
BOOK REVIEWS
227
T. W i n o g r a d and F. Flores, Understanding Computers and Cognition: A New Foundation for Design (Ablex, Norwood, NJ, 1986); 207 pages, $24.95.
Reviewed by: Lucy A. Suchman
Xerox Palo Alto Research Center, Palo Alto, CA 94304, U.S.A. There are two kinds of books in the world. On the one hand, there are those books that fall neatly into a particular intellectual tradition, to which they contribute some development, clarification, or revision of received ideas. For such books, the critical question is what is their thesis, and how well do they succeed in its exposition. On the other hand, there are those books, which tend to come along less often, that aim to challenge the basic soundness of received ideas, and to propose radical alternatives. Understanding Computers and Cognition aims to be this second kind; namely, a radical book, which should be read as such. Taken as a radical book, the question to ask about Understanding Computers and Cognition, beyond how well it succeeds in its arguments, is whether those arguments are about something important. The answer to that question, I believe, is an unequivocal yes. Winograd and Flores start with the premise that any theorizing about how the world works, or how some part of it works, will be embedded in a particualr intellectual tradition. Both because tradition provides us with ways of seeing, and because it constrains our view, tradition shapes our understanding. To go beyond the limits of a tradition, or to effect radical changes in our view, requires that we explicate and reconsider the tradition's underlying assumptions. With respect to computers and cognition, this means reconsidering the assumptions that underlie what Winograd and Flores call the "rationalistic" tradition. The authors provide various examples of what the tradition assumes, including the following ideas about problem solving, meaning, mind, rational action, and cognition: - P r o b l e m solving requires the representation of a situation in terms of identifiable objects with well-defined properties, and the logical application of general rules to situations so represented (p. 15). -Meaning can be analyzed in terms of the correspondence between sentences in a natural language, and interpretations in a formal language for which the rules of reasoning are well defined (pp. 17-19). - M i n d is the logical manipulation of mental representations, treated as sentences in an "internal language" (p. 20). - Rational behavior is a consequence of selecting among alternative courses of action, according to a comparative evaluation of outcomes (p. 20). -Cognitive systems are symbol systems. A theory of cognition can be couched as a program in an appropriate symbolic formalism such that the
228
BOOK REVIEWS
program, when run in the appropriate environment, will produce the appropriate behavior (p. 25). To characterize something as "the rationalistic tradition," by Winograd and Flores' own admission, is inevitably to accept a measure of glibness. Important distinctions are glossed, important subtleties missed, and while everyone is included, justice is done to no one. The only excuse for such gross generalization is the possibility that what is common is more important, for certain purposes, than what is distinct. The purposes in this case are to take off one set of eyeglasses and to try on another: to imagine what other way we might look not at the cognitive sciences, but at the phenomena of cognition that we are all trying to understand. Those phenomena, on Winograd and Flores' account, are language, thought, and action. For the rationalistic tradition, they argue, and consequently for cognitive science, the machinery of mind has taken precedence in theory building, insofar as mental representations and logical operations are taken as the wellspring for cognition. In trying to imagine how it could be otherwise, Winograd and Flores take their inspiration from the biological theories of Maturana, and the philosophies of Gadamer and Heidegger, who suggest that what comes first, the basis for cognition, is an essentially unarticulated "background" of environment and experience. That background is not explicable in terms like "commonsense knowledge," or "world knowledge," or any other form of represented knowledge. Instead, thought and action are organized by what Maturana calls "structural coupling" and Heidegger "being-inthe-world," that is, an experientially based, physically embodied, and largely unarticulated relationship to one's material and social environment. The organism's knowledge of how to get around in that environment is nowhere explicitly represented, either in the organism or out in the world. It is rather a function of the interaction of structures of action, with structures of the environment, including the social and material environment that actions themselves produce. The unarticulated background of cognition, according to this view, underlies our representational machinery, but also remains outside of its grasp. This is true whether we are engaged unreflectively in some routine activity, or deliberately in the analytic construction of scientific theory. It is only when some "breakdown" occurs, causing us to want to articulate some aspect of our situation or practice and reconstruct or repair it, that the unarticulated background can be represented, and is in innumerable ways. But whatever is represented is thereby transformed into something else; namely, an articulated object, that itself relies upon and takes for granted its unarticulated circumstances. What we need in the way of cognitive theory, therefore, is an account of the process whereby articulations of situations and actions interact with their unrepresented background. And this process clearly cannot be reduced to operations over a representation.
BOOK REVIEWS
229
This alternative view of cognition has serious consequences both for artificial intelligence, and for the design of useful computer systems. In the second part of the book, Winograd and Flores turn to consider those consequences. Their summary conclusions are "that one cannot program computers to be intelligent and that we need to look in different directions for the design of powerful computer technology" (p. 93). It is worth considering each of these conclusions in turn. First, with respect to intelligence, Winograd and Flores appear to believe that research in AI is so deeply misguided about the nature of intelligence, that it can contribute little to our understanding. In their concern with the hegemony of received perspectives, Winograd and Flores come close to agreeing with the old adage that AI as presently constituted is equivalent to the tree-climber who believes that by that route he is moving closer to the moon. But the adage assumes that the only measure of success is actually getting to the moon; that there are not important lessons to be learned along the way, or from attempts to move closer that fail. Insofar as the climber masks the failures, or ignores the dead ends, there surely is nothing to be learned. But the failures of AI, in principle at least, can be as valuable as its successes. That is to say, while research in AI may not get us to an artificial intelligence soon, or even ever, in principle it can still contribute to our understanding of human intelligence, through its efforts to get closer. Pushing a particular approach to the limit, like the application of logic to the control of situated action, or the stipulation of commonsense knowledge, can clarify what remains outside of that approach's grasp. But for such encounters with the limit to be instructive rather than destructive requires two things. First, an intellectual honesty on the part of researchers regarding the frustrations and downright failures of their efforts, as well as their successes. And in the case of AI, a clear distinction between the basis for evaluating technology, and the basis for evaluating long-term research. With respect to technology, we need to question whether or not, given the state of the art, AI holds the best hope for appropriate and useful technologies in a given domain. With respect to long-term research, we need to consider that it is the exploration that is the payoff, including understanding what isn't working and why, rather than any foreseeable applications. What is crucial in the latter case is not so much that the current research direction should be right, but that it should be elucidating, tentative, and open always to radical redirection based not only on advances but, more importantly, on obstacles discovered in its path. Winograd and Flores' second conclusion concerns the consequences of their view for computer systems design. Winograd and Flores view computers as tools not for theory building, but to support human activities, while transforming them for the better. They suggest that while the tradition on which current discourse about computers is based "provides a fertile background for developing new technology, it does not support an adequate understanding of what computer devices do in a context of human practice" (p. 4). Their goal is to
230
BOOK REVIEWS
provide an alternative orientation, one that can serve as a basis for the design of technology rooted in that more adequate understanding. What they offer as an exemplary case is a system called the Coordinator, intended to support communication within organizations. The idea behind the Coordinator is that organizations are held together by commitments: acts of communication that establish more and less temporary relations of interdepency among organization members. The goal of the Coordinator is not only to act as a tool with which people can make their commitments to each other, but also to reify those commitments, in the form of traces of the relevant communication that can be called up, consulted, cited, renegotiated, or whatever. The design rationale is an assertion that explicit commitments are better than implicit ones; that vagueness and ambiguity in communication over commitments is a source of organizational trouble, and that if people were to make their commitments (or their unwillingness to commit) explicit, organizational operations would be improved. Like most computer systems, the design of the Coordinator appears to be based on a combination of intuitions and received theoretical commitments. The intuitions, presumably (though we are not actually told this), come out of Fernando Flores' personal and professional experience in management and management consulting. The received theory is a variation on speech act theory, which Winograd and Flores claim "challenges the rationalistic tradition by suggesting that language, and therefore thought, is ultimately based on social interaction" (p. 11). Unfortunately, the challenge is not that easy to mount. In fact, far from challenging the view that language use can be reduced to logical operations, speech act theory can be seen to extend that view, by making communication just another form of rational action [5]. The Coordinator reifies speech act theory, on the claim that "[m]uch of the work that managers do is concerned with initiating, monitoring, and above all coordinating the networks of speech acts that constitute social action" (p.12). But we see no evidence in support of the claim that speech act theory captures what managers do, or that the Coordinator, in reifying that theory, constitutes a useful managerial tool. The concern with making things explicit, moreover, seems in some ways to contradict Winograd and Flores' commitment to understanding things in terms of their relation to an unarticulated background of community and practice. If this contradiction is deliberate, and intended to be therapeutic--"unconcealing" the commitments implicit in a communication makes better communicat i o n - w e need to be convinced both that implicit commitments constitute a problem, and that their explication is the appropriate solution. What Winograd and Flores, and the rest of us, really need in sum is less a prototype system, than a prototype process for new technology design. The complaint here is not so much that Winograd and Flores do not provide us with
BOOK REVIEWS
231
an articulation of that process themselves, as that they fail to recognize its importance, or even to indicate what its nature might be. While arguing for a concern with the sociological foundations of design, they offer neither a rich sociological theory, nor a strong method with which to uncover or build those foundations. The tools required are by no means ready for purchase off the shelf. Interestingly, however, the last 20 years have seen the emergence of a field of social studies based in a critique of traditional sociology that has much in common with Winograd and Flores' critique of the logical positivist tradition in philosophy, linguistics, and psychology. Ethnomethodology, as this field is called, takes its name from a concern not with methods for doing sociology, but with the methods by which members of the society produce mutually intelligible action in the course of their everyday lives. (For an introduction, see [3].) Like Heidegger, ethnomethodological studies start from the premise that socially organized activities are not adequately explained with reference to some body of rules that members of the society obey. Rather, the orderliness of the social world is based in the structures of everyday, practical activities. Those structures are not the reflection of underlying rules or norms, but are the product of methodical, systematic ways of organizing actions, however unique or idiosyncratic, so as to render them interpretable by other members of the community. What traditional social science takes to be the social facts that constrain appropriate behavior, ethnomethodology views as the emergent product of situated practices. And what traditional behavioral science takes to be essentially cognitive phenomena, are taken by ethnomethodology to have an essential relationship to a publicly available, socially organized world of material artifacts and situated actions. In order to believe in the appropriateness of a new technology to what people do, we need more than an assertion of the fit. We need to know what the setting is, how the activities of that particular setting are organized at present, what in the present organization of activities is troublesome and what of that seems amenable to computerization, how the design of technology can be informed by such an understanding of the setting and its activities, and what actually happens when the new technology comes into use. And we need to know these things through systematic analyses. To get the latter, we need a sound methodology for the study and description of situated human practices, and the application of such descriptions to the design of tools; a need that itself delineates a major interdisciplinary research programme. Because those social scientists involved in studies of situated activities (see, for example, [1, 2, 4, 6]) have not by and large been concerned with technology, their studies tend to be published by presses not often read by those involved in technology design, and to have no clear relation to design problems. While not concerned with technology design, however, they do offer a model for the systematic analysis of what people do, including the relation of what they do to their technologies.
232
BOOK REVIEWS
Understanding Computers and Cognition is an extremely important book, not because it provides a ready-made set of answers, but because it raises hard questions about the current premises and practices of cognitive science and computer design. It is not a textbook, but a book to argue with and talk about. If the discussions reduce to complaints about the particular characterizations offered, the book's value to the community will be minimized. But if the discussions are about not only this book, but what this b o o k is about, then we may in fact gain new orientations toward cognitive science and computer design. And if Winograd and Flores manage to stir up those winds of change, they will have made a contribution indeed.
ACKNOWLEDGMENT Thanks to Susan Newman, Debbie Tatar, and Randy Trigg of the Intelligent Systems Lab, Xerox PARC, for helping to clarify these reactions. REFERENCES 1. Atkinson, J.M. and Drew, P., Order in Court: The Organization of Verbal Interaction in Judicial Settings (Macmillan, London, 1979). 2. Garfinkel, H., Studies in Ethnomethodology (Prentice-Hall, Englewood Cliffs, 1967). 3. Heritage, J., Garfinkel and Ethnomethodology (Polity Press, Cambridge, U.K., 1984). 4. Lynch, M., Art and Artefacts in Laboratory Science (Routledge & Kegan Paul, London, 1985). 5. Suchman, L., Plans and Situated Actions: The Problem of Human-Machine Communication (Cambridge University Press, Cambridge, U.K., 1987). 6. Zimmerman, D., The practicalities of rule use, in: J. Douglas (Ed.), Understanding Every Life (Routledge & Kegan Paul, London, 1971),
T. Winograd and F. Flores, Understanding Computers and Cognition: A New Foundation for Design (Ablex, Norwood, NJ, 1986); 207 pages, $24.95. Reviewed by: William J. Clancey Stanford Knowledge Systems Laboratory, Palo Alto, CA 94304, U.S.A.
I. Introduction Every triumphant theory passes through three stages: first it is dismissed as untrue; then it is rejected as contrary to religion; finally, it is accepted as dogma and each scientist claims that he had long appreciated the truth. (Gould [6] quoting embryologist yon Baer)
227
T. W i n o g r a d and F. Flores, Understanding Computers and Cognition: A New Foundation for Design (Ablex, Norwood, NJ, 1986); 207 pages, $24.95.
Reviewed by: Lucy A. Suchman
Xerox Palo Alto Research Center, Palo Alto, CA 94304, U.S.A. There are two kinds of books in the world. On the one hand, there are those books that fall neatly into a particular intellectual tradition, to which they contribute some development, clarification, or revision of received ideas. For such books, the critical question is what is their thesis, and how well do they succeed in its exposition. On the other hand, there are those books, which tend to come along less often, that aim to challenge the basic soundness of received ideas, and to propose radical alternatives. Understanding Computers and Cognition aims to be this second kind; namely, a radical book, which should be read as such. Taken as a radical book, the question to ask about Understanding Computers and Cognition, beyond how well it succeeds in its arguments, is whether those arguments are about something important. The answer to that question, I believe, is an unequivocal yes. Winograd and Flores start with the premise that any theorizing about how the world works, or how some part of it works, will be embedded in a particualr intellectual tradition. Both because tradition provides us with ways of seeing, and because it constrains our view, tradition shapes our understanding. To go beyond the limits of a tradition, or to effect radical changes in our view, requires that we explicate and reconsider the tradition's underlying assumptions. With respect to computers and cognition, this means reconsidering the assumptions that underlie what Winograd and Flores call the "rationalistic" tradition. The authors provide various examples of what the tradition assumes, including the following ideas about problem solving, meaning, mind, rational action, and cognition: - P r o b l e m solving requires the representation of a situation in terms of identifiable objects with well-defined properties, and the logical application of general rules to situations so represented (p. 15). -Meaning can be analyzed in terms of the correspondence between sentences in a natural language, and interpretations in a formal language for which the rules of reasoning are well defined (pp. 17-19). - M i n d is the logical manipulation of mental representations, treated as sentences in an "internal language" (p. 20). - Rational behavior is a consequence of selecting among alternative courses of action, according to a comparative evaluation of outcomes (p. 20). -Cognitive systems are symbol systems. A theory of cognition can be couched as a program in an appropriate symbolic formalism such that the
228
BOOK REVIEWS
program, when run in the appropriate environment, will produce the appropriate behavior (p. 25). To characterize something as "the rationalistic tradition," by Winograd and Flores' own admission, is inevitably to accept a measure of glibness. Important distinctions are glossed, important subtleties missed, and while everyone is included, justice is done to no one. The only excuse for such gross generalization is the possibility that what is common is more important, for certain purposes, than what is distinct. The purposes in this case are to take off one set of eyeglasses and to try on another: to imagine what other way we might look not at the cognitive sciences, but at the phenomena of cognition that we are all trying to understand. Those phenomena, on Winograd and Flores' account, are language, thought, and action. For the rationalistic tradition, they argue, and consequently for cognitive science, the machinery of mind has taken precedence in theory building, insofar as mental representations and logical operations are taken as the wellspring for cognition. In trying to imagine how it could be otherwise, Winograd and Flores take their inspiration from the biological theories of Maturana, and the philosophies of Gadamer and Heidegger, who suggest that what comes first, the basis for cognition, is an essentially unarticulated "background" of environment and experience. That background is not explicable in terms like "commonsense knowledge," or "world knowledge," or any other form of represented knowledge. Instead, thought and action are organized by what Maturana calls "structural coupling" and Heidegger "being-inthe-world," that is, an experientially based, physically embodied, and largely unarticulated relationship to one's material and social environment. The organism's knowledge of how to get around in that environment is nowhere explicitly represented, either in the organism or out in the world. It is rather a function of the interaction of structures of action, with structures of the environment, including the social and material environment that actions themselves produce. The unarticulated background of cognition, according to this view, underlies our representational machinery, but also remains outside of its grasp. This is true whether we are engaged unreflectively in some routine activity, or deliberately in the analytic construction of scientific theory. It is only when some "breakdown" occurs, causing us to want to articulate some aspect of our situation or practice and reconstruct or repair it, that the unarticulated background can be represented, and is in innumerable ways. But whatever is represented is thereby transformed into something else; namely, an articulated object, that itself relies upon and takes for granted its unarticulated circumstances. What we need in the way of cognitive theory, therefore, is an account of the process whereby articulations of situations and actions interact with their unrepresented background. And this process clearly cannot be reduced to operations over a representation.
BOOK REVIEWS
229
This alternative view of cognition has serious consequences both for artificial intelligence, and for the design of useful computer systems. In the second part of the book, Winograd and Flores turn to consider those consequences. Their summary conclusions are "that one cannot program computers to be intelligent and that we need to look in different directions for the design of powerful computer technology" (p. 93). It is worth considering each of these conclusions in turn. First, with respect to intelligence, Winograd and Flores appear to believe that research in AI is so deeply misguided about the nature of intelligence, that it can contribute little to our understanding. In their concern with the hegemony of received perspectives, Winograd and Flores come close to agreeing with the old adage that AI as presently constituted is equivalent to the tree-climber who believes that by that route he is moving closer to the moon. But the adage assumes that the only measure of success is actually getting to the moon; that there are not important lessons to be learned along the way, or from attempts to move closer that fail. Insofar as the climber masks the failures, or ignores the dead ends, there surely is nothing to be learned. But the failures of AI, in principle at least, can be as valuable as its successes. That is to say, while research in AI may not get us to an artificial intelligence soon, or even ever, in principle it can still contribute to our understanding of human intelligence, through its efforts to get closer. Pushing a particular approach to the limit, like the application of logic to the control of situated action, or the stipulation of commonsense knowledge, can clarify what remains outside of that approach's grasp. But for such encounters with the limit to be instructive rather than destructive requires two things. First, an intellectual honesty on the part of researchers regarding the frustrations and downright failures of their efforts, as well as their successes. And in the case of AI, a clear distinction between the basis for evaluating technology, and the basis for evaluating long-term research. With respect to technology, we need to question whether or not, given the state of the art, AI holds the best hope for appropriate and useful technologies in a given domain. With respect to long-term research, we need to consider that it is the exploration that is the payoff, including understanding what isn't working and why, rather than any foreseeable applications. What is crucial in the latter case is not so much that the current research direction should be right, but that it should be elucidating, tentative, and open always to radical redirection based not only on advances but, more importantly, on obstacles discovered in its path. Winograd and Flores' second conclusion concerns the consequences of their view for computer systems design. Winograd and Flores view computers as tools not for theory building, but to support human activities, while transforming them for the better. They suggest that while the tradition on which current discourse about computers is based "provides a fertile background for developing new technology, it does not support an adequate understanding of what computer devices do in a context of human practice" (p. 4). Their goal is to
230
BOOK REVIEWS
provide an alternative orientation, one that can serve as a basis for the design of technology rooted in that more adequate understanding. What they offer as an exemplary case is a system called the Coordinator, intended to support communication within organizations. The idea behind the Coordinator is that organizations are held together by commitments: acts of communication that establish more and less temporary relations of interdepency among organization members. The goal of the Coordinator is not only to act as a tool with which people can make their commitments to each other, but also to reify those commitments, in the form of traces of the relevant communication that can be called up, consulted, cited, renegotiated, or whatever. The design rationale is an assertion that explicit commitments are better than implicit ones; that vagueness and ambiguity in communication over commitments is a source of organizational trouble, and that if people were to make their commitments (or their unwillingness to commit) explicit, organizational operations would be improved. Like most computer systems, the design of the Coordinator appears to be based on a combination of intuitions and received theoretical commitments. The intuitions, presumably (though we are not actually told this), come out of Fernando Flores' personal and professional experience in management and management consulting. The received theory is a variation on speech act theory, which Winograd and Flores claim "challenges the rationalistic tradition by suggesting that language, and therefore thought, is ultimately based on social interaction" (p. 11). Unfortunately, the challenge is not that easy to mount. In fact, far from challenging the view that language use can be reduced to logical operations, speech act theory can be seen to extend that view, by making communication just another form of rational action [5]. The Coordinator reifies speech act theory, on the claim that "[m]uch of the work that managers do is concerned with initiating, monitoring, and above all coordinating the networks of speech acts that constitute social action" (p.12). But we see no evidence in support of the claim that speech act theory captures what managers do, or that the Coordinator, in reifying that theory, constitutes a useful managerial tool. The concern with making things explicit, moreover, seems in some ways to contradict Winograd and Flores' commitment to understanding things in terms of their relation to an unarticulated background of community and practice. If this contradiction is deliberate, and intended to be therapeutic--"unconcealing" the commitments implicit in a communication makes better communicat i o n - w e need to be convinced both that implicit commitments constitute a problem, and that their explication is the appropriate solution. What Winograd and Flores, and the rest of us, really need in sum is less a prototype system, than a prototype process for new technology design. The complaint here is not so much that Winograd and Flores do not provide us with
BOOK REVIEWS
231
an articulation of that process themselves, as that they fail to recognize its importance, or even to indicate what its nature might be. While arguing for a concern with the sociological foundations of design, they offer neither a rich sociological theory, nor a strong method with which to uncover or build those foundations. The tools required are by no means ready for purchase off the shelf. Interestingly, however, the last 20 years have seen the emergence of a field of social studies based in a critique of traditional sociology that has much in common with Winograd and Flores' critique of the logical positivist tradition in philosophy, linguistics, and psychology. Ethnomethodology, as this field is called, takes its name from a concern not with methods for doing sociology, but with the methods by which members of the society produce mutually intelligible action in the course of their everyday lives. (For an introduction, see [3].) Like Heidegger, ethnomethodological studies start from the premise that socially organized activities are not adequately explained with reference to some body of rules that members of the society obey. Rather, the orderliness of the social world is based in the structures of everyday, practical activities. Those structures are not the reflection of underlying rules or norms, but are the product of methodical, systematic ways of organizing actions, however unique or idiosyncratic, so as to render them interpretable by other members of the community. What traditional social science takes to be the social facts that constrain appropriate behavior, ethnomethodology views as the emergent product of situated practices. And what traditional behavioral science takes to be essentially cognitive phenomena, are taken by ethnomethodology to have an essential relationship to a publicly available, socially organized world of material artifacts and situated actions. In order to believe in the appropriateness of a new technology to what people do, we need more than an assertion of the fit. We need to know what the setting is, how the activities of that particular setting are organized at present, what in the present organization of activities is troublesome and what of that seems amenable to computerization, how the design of technology can be informed by such an understanding of the setting and its activities, and what actually happens when the new technology comes into use. And we need to know these things through systematic analyses. To get the latter, we need a sound methodology for the study and description of situated human practices, and the application of such descriptions to the design of tools; a need that itself delineates a major interdisciplinary research programme. Because those social scientists involved in studies of situated activities (see, for example, [1, 2, 4, 6]) have not by and large been concerned with technology, their studies tend to be published by presses not often read by those involved in technology design, and to have no clear relation to design problems. While not concerned with technology design, however, they do offer a model for the systematic analysis of what people do, including the relation of what they do to their technologies.
232
BOOK REVIEWS
Understanding Computers and Cognition is an extremely important book, not because it provides a ready-made set of answers, but because it raises hard questions about the current premises and practices of cognitive science and computer design. It is not a textbook, but a book to argue with and talk about. If the discussions reduce to complaints about the particular characterizations offered, the book's value to the community will be minimized. But if the discussions are about not only this book, but what this b o o k is about, then we may in fact gain new orientations toward cognitive science and computer design. And if Winograd and Flores manage to stir up those winds of change, they will have made a contribution indeed.
ACKNOWLEDGMENT Thanks to Susan Newman, Debbie Tatar, and Randy Trigg of the Intelligent Systems Lab, Xerox PARC, for helping to clarify these reactions. REFERENCES 1. Atkinson, J.M. and Drew, P., Order in Court: The Organization of Verbal Interaction in Judicial Settings (Macmillan, London, 1979). 2. Garfinkel, H., Studies in Ethnomethodology (Prentice-Hall, Englewood Cliffs, 1967). 3. Heritage, J., Garfinkel and Ethnomethodology (Polity Press, Cambridge, U.K., 1984). 4. Lynch, M., Art and Artefacts in Laboratory Science (Routledge & Kegan Paul, London, 1985). 5. Suchman, L., Plans and Situated Actions: The Problem of Human-Machine Communication (Cambridge University Press, Cambridge, U.K., 1987). 6. Zimmerman, D., The practicalities of rule use, in: J. Douglas (Ed.), Understanding Every Life (Routledge & Kegan Paul, London, 1971),
T. Winograd and F. Flores, Understanding Computers and Cognition: A New Foundation for Design (Ablex, Norwood, NJ, 1986); 207 pages, $24.95. Reviewed by: William J. Clancey Stanford Knowledge Systems Laboratory, Palo Alto, CA 94304, U.S.A.
I. Introduction Every triumphant theory passes through three stages: first it is dismissed as untrue; then it is rejected as contrary to religion; finally, it is accepted as dogma and each scientist claims that he had long appreciated the truth. (Gould [6] quoting embryologist yon Baer)