Setting Off on the Right Foot
Daniel C. Dennett
From D.C. Dennett, The Intentional Stance (Cambridge, Mass.: MIT Press, 1987)
Talking about the mind, for many people, is rather like talking about sex: slightly embarrassing, undignified, maybe even disreputable. "Of course it exists," some might say, "but do we have to talk about it?" Yes, we do. Many people would rather talk about the brain (which, after all, is the mind) and would like to think that all the wonderful things we need to say about people could be said without lapsing into vulgar, undisciplined mentalistic talk, but it is now quite clear that many things need saying that cannot be said in the restricted languages of neuroanatomy, neurophysiology, or behavioristic psychology. It is not just the arts and humanities that need to talk about the mind; the various puritanical attempts to complete the biological and social sciences without ever talking about it have by now amply revealed their futility.
In fact there is something approaching a new consensus among cognitive scientists and the more liberated neuroscientists, to the effect that there can be-must be, somehow-a responsible, materialistic science not only of the brain, but also of the mind. There is no consensus yet, however, about just how this responsible science of the mind will be conducted.
This book is about how to talk about the mind. It is a philosophical book, written by a philosopher and dealing primarily with the issues as they have appeared in the philosophical literature; but it is not for philosophers only. Those in other disciplines who are newly eager, or at any rate reluctantly willing, to indulge in various mentalistic sorts of talk find that philosophers, who have never been shy about talking about the mind, have a lot to tell them about how to do it. In fact we philosophers have rather too much to tell. Only a small portion of what we have said could possibly be true, or useful, and much of even the best is apt to be misinterpreted. Philosophy does not often produce stable, reliable "results" the way science does at its best. It can, however, produce new ways of looking at things, ways of thinking about things, ways of framing the questions, ways of seeing what is important and why.
This can be a valuable contribution, since everyone who is trying to think about the mind is beset by tactical problems about which questions to try to answer. We are all faced with the baffling phenomena; how could anything be more familiar, and at the same time more weird, than a mind? We also have an overwhelming array of data about the most complex object we have encountered in the universe-the human brain-and about the enormous variety of behavior that brain can modulate. Finally, we are bemused by an intrusive gaggle of persistent intuitions deriving from heaven knows where. Theorists in every field, then, run the risk of following their distinguished predecessors and setting off on the wrong foot because of one "philosophical" misconception or another about the nature of the phenomena, the range of available theoretical options, the shape of the theoretical tasks, or the conditions that must be met by a successful account of the mind.
There is no way to avoid having philosophical preconceptions; the only option is whether to examine them explicitly and carefully at some point in one's endeavors. It is of course possible that some of today's philosophically untutored theorists are lucky enough to harbor only the soundest philosophical preconceptions-perhaps the ambience of the age will ensure this without any direct communication with philosophers. And it must certainly be borne in mind that some of the most debilitating philosophical misconceptions of the past have been all too potent gifts from academic philosophy that scientists have misconstrued, typically by enthusiastic exaggeration and oversimplification: logical positivism and, more recently, incommensurability of Kuhnian paradigms come to mind. Still, we philosophers think we can help and are gratified to find a growing number of others who have turned to us for help-with an entirely appropriate attitude of cautious skepticism.
This book presents the foundations for my theory of the mind: my account of the intentional stance. Those familiar with that account will find few major innovations of theory but several innovations of exposition and defense, especially in the reflections following each reprinted essay, where I attempt to clarify and amplify my previous arguments. The last chapter is devoted to a systematic comparison of my view with others that have been defended recently, using the criticisms and objections of others to focus the problematic points. In these new essays I have tried to present and answer all the objections to my account that have appeared in the literature and to correct the misapprehensions and misconstruals. I also make explicit along the way some of the main points of agreement and disagreement with others who have written on these topics, and draw attention to some generally unrecognized implications of my position regarding current controversies.
The basic introduction to my theory of the intentional stance is to be found in the next chapter, "True Believers," which I now consider to replace "Intentional Systems" (1971) as the flagship expression of my position. In the rest of this chapter, I step back a few paces and comment on some unargued assumptions of the other essays.
Common Sense and the Third-Person Point of View
Here on planet Earth are many complicated life forms. Common sense tells us that many of them have mental lives-minds-of one dimly envisaged sort or another. What common sense tells us is not enough. Not only does it leave too many pressing questions unresolved, but it often yields persuasive intuitions that contradict each other. From some vantage points it is "obvious" that warm-blooded animals have minds like ours, while insects appear to be "mere automata"; from other vantage points the gulf between us and even the chimpanzee appears larger than the gulf between a pigeon and a robot. The idea that no automaton could possibly be conscious the way we are is perennially popular but can be made to look suspiciously unimaginative and parochial, a case of misguided wishful thinking. Some of the apparently well-attested pathologies of human mind and brain are so counterintuitive that recounting them often provokes derisive dismissal. A student of mine recently relayed to her literature professor the account I had presented in class of the strange but well-studied pathologies of blindness denial and hemi-neglect. He firmly assured her that I had been making it all up, that I must have been performing some experiment on the credulity of my students. To him it was obvious that Professor Dennett was just inventing another of his wild science-fiction fantasies, yet another intuition pump to bamboozle the gullible. When so many "obvious facts" compete with each other, common sense is not enough.
No rules govern the way we as theorists must appeal to common sense. We must all in one way or another start from the base of common sense if we hope to be understood, or to understand ourselves. But reliance on any particular item of common sense is treacherous; one person's bedrock certainty is another's spuriously convincing relic of an outmoded world view. Even if some portions of what passes as common sense are shining, immutable Truth, other portions are probably just the cognitive illusions of our speciesoverwhelmingly persuasive to us because of design shortcuts in our cognitive systems. (To a phototropic moth, it may seem to be an a priori truth that it is always Right to head toward the Light; no alternative is conceivable to it.) Other deliverances of common sense are just diluted, popularized versions of the science of yesteryear.
Sorting out these portions of common sense into the true, the false, the misleading, and the unreliable is a good task for a philosopher. Indeed philosophers specialize in this sort of task. One thing we have learned from the distinguished failures of the past is that this is not a systematic task, amenable to a purely foundational or axiomatic approach. Rather, we must wade in opportunistically and attempt to achieve a stable vision by playing off against each other a variety of intuitions, empirical findings and theories, rigorous arguments, and imaginative thought experiments.
Some useful skirmishes in this campaign do consist of rigorous, formal explorations of particular sets of hunches. That is in fact the best light in which to view the various formalist failures of philosophy-as if they had been prefaced with "What if we made these assumptions and proceeded under these constraints?" As Fodor says, "The form of a philosophical theory, often enough, is: Let's try looking over here." (1981a, p. 31) Every formal system in philosophy must be "motivated," and the informal task of providing that motivation typically contributes more philosophical illumination (or at least doctrine) than the system for which it paves the way. There is always more than one candidate system or perspective crying out for philosophical exploration and development, and in such an unruly arena of thought, tactical considerations play an unusually important role. These tactical considerations often masquerade, however, as first principles.
I begin, then, with a tactical choice. I declare my starting point to be the objective, materialistic, third-person world of the physical sciences. This is the orthodox choice today in the English-speaking philosophical world, but it has its detractors, most notably Nagel, who has devoted a book, The View From Nowhere (1986), to deploring the effects of this tactical choice. Since Nagel's is the major alternative starting point to mine, let us compare them briefly to see what we might be missing.
I am not certain that Nagel is one of those who thinks he can prove that my starting point is a mistake, but he certainly asserts that it is:
There are things about the world and life and ourselves that cannot be adequately understood from a maximally objective standpoint, however much it may extend our understanding beyond the point from which we started. A great deal is essentially connected to a particular point of view, or type of point of view, and the attempt to give a complete account of the world in objective terms detached from these perspectives inevitably leads to false reductions or to outright denial that certain patently real phenomena exist at all. (p. 7)
My intuitions about what "cannot be adequately understood" and what is "patently real" do not match Nagel's. Our tastes are very different. Nagel, for instance, is oppressed by the desire to develop an evolutionary explanation of the human intellect (pp. 78-82); I am exhilarated by the prospect. My sense that philosophy is allied with, and indeed continuous with, the physical sciences grounds both my modesty about philosophical method and my optimism about philosophical progress. To Nagel, this is mere scientism.
To the extent that such no-nonsense theories have an effect, they merely threaten to impoverish the intellectual landscape for a while by inhibiting the serious expression of certain questions. In the name of liberation, these movements have offered us intellectual repression. (p. 11)
Nagel is both courageous and clever. It takes courage to stand up for mystery, and cleverness to be taken seriously. Nagel repeatedly announces that he has no answers to the problems he raises, but prefers his mystification to the demystifying efforts of others. Oddly enough, then, Nagel would agree with me that his tactical starting point leads not just to perplexity, but to a perplexity from which he himself offers no escape. For me, that impasse is tantamount to a reductio ad absurdum of his method, but Nagel bravely recommends embracing the result:
Certain forms of perplexity-for example, about freedom, knowledge, and the meaning of life-seem to me to embody more insight than any of the supposed solutions to those problems. (p. 4)
Nagel is the most eloquent contemporary defender of the mysteries, and anyone who suspects I have underestimated the problems I pose for my theory will be braced by Nagel's contrary assertions. Assertions, not arguments. Since Nagel and I start from different perspectives, his arguments beg the question against a position like mine: what counts for him as flat obvious, and in need of no further support, often fails to impress me. I assume that whatever the true theory of the mind turns out to be, it will overturn some of our prior convictions, so I am not cowed by having the counterintuitive implications of my view pointed out. Any theory that makes progress is bound to be initially counterintuitive. No doubt Nagel, who calls his book "deliberately reactionary," is equally unshaken when it is pointed out that his allegiance to certain intuitions is all that prevents him from escaping his perplexity down various promising avenues of scientific research.
The feeling then is mutual; we beg the question against each other. I do not presuppose that an alternative starting point such as Nagel's must be wrong or that everything in the universe worth taking seriously must be accessible from my starting point. I am impressed, however, with its proven yield of (apparent) comprehension, and even more so by its promise of future harvests.
Nagel claims to show that the attempt to reconcile objective and subjective is "essentially incompletable" (p. 4), and he might be right-though I remain utterly unpersuaded. Some join him in suspecting, however, that there is something subtly incoherent in the more or less standard scientists' vision of the world and our place in it-some irresolvable conflict between the subjective and objective, between the concrete and abstract, between the macro and the micro (cf. Dennett 1984d, pp. 128-29). Doesn't the self-styled objectivist covertly depend on some prior commitment to irreducible points of view? Or doesn't the goal of "reducing" these points of view to biology to chemistry to physics defeat itself in the end in any case? It is rumored that down in the subcellars of contemporary physics the modern-day alchemists are turning materialism into idealism all over again. Quantum particles do sometimes seem to be, as David Moser has said, "the dreams stuff is made of."
Perhaps those who distrust the frankly materialistic assumptions and aspirations of the current scientific image are right to do so, but I doubt it, and choose not to confront their suspicions further at the outset. The orthodoxy today of my scientific starting point might even be due as much to social and political factors as to any philosophical justification. Although I don't believe it, I can see the plausibility in Nagel's diagnosis: "It is like the hatred of childhood and results in a vain effort to grow up too early, before one has gone through the essential formative confusions and exaggerated hopes that have to be experienced on the way to understanding anything." (p. 12)
My tactical hunch, however, is that even if this is so, the best way to come to understand the situation is by starting here and letting whatever revolutions are in the offing foment from within. I propose to see, then, just what the mind looks like from the third-person, materialistic perspective of contemporary science. I bet we can see more and better if we start here, now, than if we try some other tack. This is not just a prejudice of mine-I have shopped around-but the only way I know to convince you I am right is to get on with the project and let the results speak for themselves.
Folk Science and the Manifest Image
What then do we see when we look at this bustling public world? Among the most complicated and interesting of the phenomena are the doings of our fellow human beings. If we try to predict and describe them using the same methods and concepts we have developed to describe landslides, germination, and magnetism, we can make a few important inroads, but the bulk of their observable macroactivity-their "behavior"-is hopelessly unpredictable from these perspectives. People are even less predictable than the weather, if we rely on the scientific techniques of meteorologists and even biologists. But there is another perspective, familiar to us since childhood and used effortlessly by us all every day, that seems wonderfully able to make sense of this complexity. It is often called folk psychology. It is the perspective that invokes the family of "mentalistic" concepts, such as belief, desire, knowledge, fear, pain, expectation, intention, understanding, dreaming, imagination, self-consciousness, and so on.
The important features of folk psychology can best be highlighted by drawing out its similarity to another portion of our common endowment: folk physics. Folk physics is the system of savvy expectations we all have about how middle-sized physical objects in our world react to middle-sized events. If I tip over a glass of water on the dinner table, you leap out of your chair, expecting the water to spill over the side and soak through your clothes. You know better than to try to sop up the water with your fork, just as you know you can't tip over a house or push a chain. You expect a garden swing, when pushed, to swing back.
Some folk physics might be innate, but at least some of it must be learned. Virtually from birth, infants cringe when shapes loom, and once they develop crawling and stereovision (after about six months), they exhibit reluctance to venture out over the edge of the "visual cliff"-a clear glass surface extending out over a tabletop-even though they have never learned from bitter experience about the consequences of falling off a high place (Gibson 1969). But children have to learn from particular experiences that they cannot walk on water and that unstable towers of blocks will topple. Some folk physics seems to be supported by innate perceptual bias: when shown an animation of something apparently falling (e.g., circles of color "falling" like rain on a video screen), if the acceleration rate is tampered with, one instantly and irrepressibly sees that some invisible force is "pushing" up or down on the circles to disturb their "proper" motion.
The fact that a judgment of folk physics is innate, or just irresistible, would be no guarantee of its truth. The truth in academic physics is often strongly counterintuitive, or in other words contrary to the dictates of folk physics, and we need not descend to the perplexities of modern particle physics for examples. The naive physics of liquids would not predict such surprising and apparently magical phenomena as siphons or pipettes (Hayes 1978), and an uninitiated but clever person could easily deduce from the obvious first principles of folk physics that gyroscopes, the virtual images produced by parabolic mirrors, and even sailing upwind were flat impossible.
So it is with folk psychology. So natural and effortless are its interpretations that it is almost impossible to suppress them. Imagine watching someone picking blueberries and not having any idea what he was doing. Imagine perceiving two children tugging at the same teddy bear and not having it occur to you that they both want it. When a blind person fails to react to something right before her eyes, this can startle us, so compelling is our normal expectation that people come to believe the truth about what is happening right in front of their eyes.
Some of the categories of folk psychology, like some of those of folk physics, are apparently given an innate perceptual boost; for instance, (inconclusive) evidence from studies with infants suggests that the perception of faces as a preferred category is served by innate and somewhat specialized visual mechanisms (Maurer and Barrera 1981; but see also Goren et al. 1975 and Cohen, DeLoache, and Strauss 1979). An adult who could not interpret a threatening (or seductive) gesture as such would be suspected of brain damage, not just of having led a sheltered life. And yet there is much that we must learn, at mother's knee and even in school, before we become adept at "reading" the behavior of others in mentalistic terms (see, e.g., Shaftz, Wellman, and Silver 1983; Wimmer and Perner 1983).
The intuitions generated by folk psychology are probably no more irresistible initially than those of folk physics, but perhaps because of the relatively undeveloped and unauthoritative state of academic psychology (including its close relatives, the neurosciences), there are few well-known uncontroversial cases of science directly discrediting a folk-psychological intuition.
What are the siphons and gyroscopes of psychology? As Churchland (1986) notes, "So long as the brain functions normally, the inadequacies of the commonsense framework can be hidden from view, but with a damaged brain the inadequacies of theory are unmasked." (p. 223) So we should look first at the puzzling abnormal cases. Blindsight (Weiskrantz 1983) and the split-brain phenomena (Gazzaniga 1985) have already attracted the attention of philosophers (e.g., Marks 1980 and Nagel 1979), and then there are the blindness denial and hemi-neglect that the literature professor thought I was making up. (Churchland 1986, pp. 222-35, offers an introductory survey. Sacks 1984, 1986 provides vivid descriptions of some particularly bizarre cases, including his own experience with the temporary "loss" of his left leg.) Academic psychology does not yet have an established theory of these phenomena to hold up against our folk incredulity, so they remain controversial, to say the least.
No one doubts that there are perceptual illusions, and some of these-for example, the Ames distorting room (Ittleson 1952; Gregory 1977)-outrage our naive expectations. Then there are the masochists, who are reputed to like pain (?!), and the legion of legendary (and indeed sometimes mythical) idiot savants (Smith 1983). Finally there are the people who supposedly have photographic memories, or multiple personalities, to say nothing (and I mean it) of those with alleged psychic powers. This motley assortment of challenges to our everyday psychological hunches should have been enough to make us all cautious when advancing a priori claims based on an analysis of the everyday concepts about what can and cannot happen, but philosophers have typically invested a surprising authority in those concepts. Consider the philosophical debates about self-deception and weakness of the will. No one doubts that the phenomena so-called by folk psychology are ubiquitous. The controversy reigns over how, if at all, these phenomena can be described coherently in terms of belief, knowledge, intention, judgment, and the other standard terms of folk psychology. Articles with titles like "How is Weakness of Will Possible?" (Davidson 1969) attempt to say just exactly what one must believe, think, know, intend, and want in order to suffer a genuine case of weakness of will. The paradoxes and contradictions that bedevil the attempts have discouraged few of the participants. It is apparently obvious to them that the folk-psychological categories they learned in infancy are the right categories to use, whatever Nagelian perplexity their use may bring in its train.
We have all learned to take a more skeptical attitude toward the dictates of folk physics, including those robust deliverances that persist in the face of academic science. Even the "undeniable introspective fact" that you can feel "centrifugal force" cannot save it, except for the pragmatic purposes of rough-and-ready understanding it has always served. The delicate question of just how we ought to express our diminished allegiance to the categories of folk physics has been a central topic in philosophy since the seventeenth century, when Descartes, Boyle, and others began to ponder the metaphysical status of color, felt warmth, and the other "secondary qualities." These discussions, while cautiously agnostic about the status of folk physics, have traditionally assumed as unchallenged bedrock the folk-psychological counterpart categories: conscious perceptions of color, sensations of warmth, or beliefs about the "external world," for instance. (This assumption is particularly evident in Kripke's (1972) discussion of materialism, for example.)
A few of us (Quine 1960; Dennett 1969, 1978a; Churchland 1981; Stich 1983) have wondered if the problems encountered in traditional philosophy of mind may be problems with the whole framework or system of folk-psychological concepts, and have recommended putting those concepts in the same jeopardy as the concepts of folk physics. We have disagreed on the verdict, a topic for exploration in the chapters ahead, but not on the vulnerability in principle of the mentalistic concepts.
The faith we are all tempted to place in the categories of folk psychology, like our faith in the categories of folk physics, is not due just to stubborn loyalty to the world view we grew up with. In his classic essay "Philosophy and the Scientific Image of Man," Sellars (1963, chapter 1) calls this world view the manifest image and distinguishes it from the scientific image. It is no accident that we have the manifest image that we do; our nervous systems were designed to make the distinctions we need swiftly and reliably, to bring under single sensory rubrics the relevant common features in our environment, and to ignore what we can usually get away with ignoring (Dennett 1984d, forthcoming a; Akins, unpublished). The undeniable fact is that usually, especially in the dealings that are most important in our daily lives, folk science works. Thanks to folk physics we stay warm and well fed and avoid collisions, and thanks to folk psychology we cooperate on multiperson projects, learn from each other, and enjoy periods of local peace. These benefits would be unattainable without extraordinarily efficient and reliable systems of expectation-generation.
How are we enabled to do all this? What organizes our capacity to have all these effortless, confident, and largely reliable expectations? Are there general "laws" or "principles" of folk physics that we somehow internalize and then unconsciously exploit to generate the indefinitely various and sensitive expectations we have about inanimate objects? How do we manage to acquire such a general capacity to interpret our fellow human beings? I have no account to offer of our talents as folk physicists, or about the relation of folk physics to its academic offspring (though this is a fascinating topic deserving further study), but I do have an explanation of the power and success of folk psychology: we make sense of each other by adopting the intentional stance.