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Out of the Matrix

How the late philosopher Donald Davidson showed that reality can't be an illusion

MAYBE LIFE IS A DREAM. Maybe reality is utterly different from what it appears to be. Maybe human language is inadequate to represent that reality. Maybe our minds simply cannot grasp what is going on. Maybe we are just brains in vats, fed electrical impulses that alter our brain-states, thereby creating pseudo-experiences of an imaginary world.

This string of skeptical "maybes" is our heritage from Ren Descartes, an undeservedly influential 17th-century philosopher who suggested that what goes on in our minds might have nothing to do with what goes on outside them. One reason movies like "The Matrix" are popular is that people find it stimulating to work through some of the paradoxical consequences of this suggestion. That is also why many students enjoy philosophy courses in which they are asked to ponder such far-out possibilities as "the inverted spectrum" -- the hypothesis that, thanks to sex-linked neurological differences, when men look up at a clear sky, they see the color that women see when they look at fire engines, and conversely. The men's color spectrum is an inversion of the women's. But since the men and the women apply the words "blue," "red," and so forth to the same objects, they will never know that they live in differently colored worlds.

Philosophy in the 20th century has finally begun to get over its centuries-long obsession with this Cartesian caricature of the human situation. Nowadays many philosophers make fun of the suggestion that the mind is a private place in which an inner eye watches scenes unfolding on the screen of an inner theater, scenes that may have nothing to do with what happens outside, in the real world. The two philosophers who did the most to persuade us not to take this suggestion seriously were the brilliant and eccentric Viennese Ludwig Wittgenstein and Donald Davidson, a professor of philosophy at Berkeley and elsewhere who died on Aug. 30 at the age of 86.

. . .

Wittgenstein wrote aphorisms that were suggestive but hard to interpret. Arguing that there was no point in talking about the "intrinsic quality" of a sensation, for example, he said, "A wheel that can be turned though nothing else turns with it, is not part of the mechanism." Davidson, one of the most respected and influential philosophers of his time, wrote intricately argued articles for a specialist audience. But those articles made it possible to see what Wittgenstein had been getting at. For Davidson gave careful and systematic articulation to a non-Cartesian account of the relations between mind, language, and world -- an account that Wittgenstein had merely sketched.

Both philosophers asked us to stop thinking of language as an attempt to communicate the content of nonlinguistic experiences. We should, they argued, stop thinking of our minds as inner theaters. Instead we should think of the possession of a mind -- the feature that distinguishes humans from brutes -- as the ability to use language in order to coordinate our actions with those of other people. We need not worry about the adequacy of our language to describe reality, for human languages are as they are, contain the words they do, because they have been shaped by interaction with the nonhuman universe.

One way to sum up this anti-Cartesian line of thought is to say that words acquire their meanings by being used in roughly similar ways by most speakers, not by being paired off with particular experiences or objects. (If men and women consistently use "blue" in the same way on the same occasions, they automatically mean the same thing by "blue.") Another is to say that we call beliefs "true" when they cohere with the rest of our beliefs, not by seeing how well they fit nonwords.

In a 1983 paper titled "A Coherence Theory of Truth and Knowledge," Davidson startled the philosophical world by pointing out that this Wittgensteinian way of thinking entails that most of anybody's beliefs about anything must be true. His point was that you have to have a lot of true beliefs about something before you can have any false ones.

Take beavers, for example. If you believe that beavers live in deserts, are pure white in color, and weigh 300 pounds when adult, then you do not have any beliefs, true or false, about beavers. For you are using the word "beaver" in a way that has no connection with its ordinary use. What the rest of us mean by the word "beaver" is a function of our commonly held beliefs about beavers. If the beliefs you express by sentences using the word "beaver" are too different from ours, then we are not talking about the same things.

Even if they grant this point, philosophers who remain loyal to Descartes will fall back on asking: What if there are no beavers? Maybe beavers are illusions. You cannot have true beliefs about illusions, can you? If you do not know what is really real and what merely seems to be real (and how could you, since you might be a brain in a vat or a character in "The Matrix") then you are not in a position to say that you have any true beliefs.

Davidson would reply that Cartesian skeptics are misusing the expression "really real." It makes sense to say that the people I encounter in my dreams, or the things I see after taking hallucinogens, are not really real. For denying them reality is just a way of saying that we cannot make beliefs about these people or things cohere with the rest of our beliefs -- specifically, with our beliefs about other people and things. The expression "not really real" is, in such contexts, given its meaning by contrasting cases in which we are prepared to say that those other people or things are really real.

Davidson's point is that retail skepticism makes sense, but wholesale skepticism does not. We have to know a great deal about what is real before we can call something an illusion, just as we have to have a great many true beliefs before we can have any false ones. The proper reply to the suggestion that beavers might be illusory is this: Illusory by comparison to what?

Even a mind-bending movie like "The Matrix" supports this insight. If you see the film after having read Davidson, you will be struck by the fact that the hero has mostly the same beliefs after he is ripped out of his artificial environment as he did before. He still believes millions of the same commonplaces -- the commonplaces that make it possible for him to use the same language outside the Matrix that he used inside it. He had been fooled about what was going on around him, but had never been fooled about what sorts of things the world contains, what is good and what evil, the color of the sky, the warmth of the sun, or the salient features of beavers.

. . .

In a famous article of 1974 titled "On the Very Idea of a Conceptual Scheme," Davidson explained why we did not have to worry about another familiar science-fiction suggestion: that an advanced civilization, flourishing in a faraway galaxy, might wield concepts that are forever beyond our grasp, concepts entirely incommensurable with our own. The reason is that every language, even the most advanced, has to get its start as a set of behavioral responses to stimuli, responses that can be correlated with our own responses. So there is no such thing as an unlearnable language.

This means that if the sounds the Galactics are making are a language at all, we can learn that language in the same way that we learned our own, and in the same way that an anthropologist learns the language of an unfamiliar tribe. We start with words like "blue" and "beaver" -- words whose utterance can be provoked by the clear sky or a small brown creature building a dam in the river -- and gradually work our way up to expressions like "blasphemous," "undemocratic," "positron," and "transfinite cardinal number."

Descartes's conception of the mind as a private inner space, and his treatment of concepts as mental entities that somehow precede language, rather than as uses of words, have done a lot for science fiction. But they have done nothing for serious thought. Wittgenstein and Davidson thought it was time for philosophers to stop fooling around with the inverted spectrum and the incommensurable Galactics. In their use of expressions like "really real" and in their attempts to make wholesale skepticism plausible, Wittgenstein said, philosophers have taken language "on holiday." We should not let our holiday entertainments distract us from serious work.

Davidson's and Wittgenstein's writings are not easy for the nonspecialist to grasp. Neither are those of Kant and Hegel. But the work of original and imaginative philosophers such as these, in the course of generations, gradually comes to have an influence on the entire culture. Their criticisms of our intellectual heritage change our sense of what it is important to think about. A couple of centuries from now, historians of philosophy will be writing about the changes in the human self-image that Donald Davidson's writings helped bring about.

Richard Rorty is a professor of comparative literature at Stanford University and the author of many books of philosophy, including "Philosophy and the Mirror of Nature" and "Achieving Our Country: Leftist Thought in 20th-Century America."

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