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Thứ Ba, 11 tháng 6, 2013


The human body is the best picture of the human soul.

Ludwig Wittgenstein, Philosophical Investigations

We recall that John B. Watson did not claim that quite all thought was incipient speech; it was all incipient twitching of muscles, and mostly of speech muscles.

W. V. Quine, “Mind and Verbal Dispositions”

We're getting down computer action
Do the robotic satisfaction

Beastie Boys, “Body Movin’”

To perceive a human being behaving in certain characteristic ways just is to perceive him as thinking.  There are two ways to read such a claim: Quine’s and Watson’s reductionist way, and Wittgenstein’s anti-reductionist way.  The Beastie Boys, of course, were putting forward a computational-functionalist variation on Quinean behaviorism.  (OK, not really.  Just pretend.  It’s a better quote than any I could have gleaned from a functionalist philosopher.)

To understand the difference between these two ways of tying thought to behavior, consider the following analogy.  There is a sense in which, at least for a speaker of English, correctly to perceive the following string of marks just is to perceive a sentence, and thus it just is to perceive something with meaning:

(1) The cat is on the mat.

It would be absurd to suggest, however, that the marks’ meaning, and thus its status as a sentence, is entirely analyzable in terms of the physical and chemical properties of the marks -- the size, shape, and color, of the marks, the chemical composition of the screen or paper and ink on which you are reading them, and so forth.  There is no relevant physical or chemical difference between the string of marks in question and the following, different string of marks:

(2) Ѳ/^◊¬¤—ĦΔſ/љℓ

(2), of course, has no meaning and is not a sentence at all.  The reason (1) is a sentence and (2) is not -- the relevant difference between (1) and (2) -- is that in English there is a set of conventions according to which marks like those in (1) count as letters and words, and letters and words arranged in just the way the marks in (1) are arranged express the proposition that the cat is on the mat.  There are no such conventions associated with (2).

When we correctly perceive (1) as a sentence, we are bringing to bear our knowledge of English.  But we are not doing so consciously, at least not in the usual circumstances.  Except in unusual cases (when trying to read very bad penmanship, say) we aren’t consciously thinking something like: “Hmm, now that first mark looks like a ‘t,’ the second like an ‘h,’ the third like an ‘e.’  I infer that that is the word ‘the,’ since there is a convention in English of using a set of marks that looks like that for the definite article.  Turning to the second set of marks, the first looks like ‘c,’ the second…”  We don’t first identify the physical properties of the marks and then, in a separate act, attribute a meaning to them.  We just see the set of marks, all at once and in an instant, as a sentence asserting that the cat is on the mat.  The physical and semantic properties form a kind of unity, phenomenologically speaking.

This is the spirit in which Wittgenstein takes it to be the case that to perceive a person’s body just is to perceive his or her soul.  In particular, correctly to perceive certain movements in the facial muscles just is to perceive worry, fear, or joy; correctly to perceive a certain pointing motion with the arm just is to perceive an intention to call our attention to something; correctly to perceive a certain tightening of the muscles and to hear a groan just is to perceive pain; and so forth.  The claim is not that these mentalistic descriptions are reducible to a description of the bodily motions.  The claim is rather that the mentalistic aspect and the bodily aspect form a kind of unity, just as with the sentence. 

The position expressed by Quine, Watson, and other reductionists is very different.  Go back to the sentence analogy.  Suppose someone suggested that the meaning of a sentence is reducible to its physical and chemical properties.  In particular, suppose he said that the meaning of (1) was entirely reducible to what could be said about the shapes and size of the marks, the chemical structure of the ink or surface of the computer screen, etc.  If such a reductionist were to hold that correctly to perceive the string of marks that makes up (1) just is to perceive it as a sentence, his claim would have a very different sense than when I made that assertion above.  He would be saying something like this: If you learn to see (1) the way you see (2) -- as a string of mere shapes having a certain size and color -- the meaning of (1) is entirely reducible to that.  He would in effect be saying that (1) in fact has no more meaning in the usual sense than (2) does, but that we should redefinethe “meaning” of a sentence so that it is just a matter of having certain physical and chemical properties.  And to learn to see all sentences this way would be to learn to see them the way you see (2).

This is, in effect, what Quine, Watson, and others would have us do vis-à-vis bodily behavior.  We are, first, to come to see bodily behavior as mere motions stripped of the meanings we usually see in them -- to see facial expressions, arm and leg movements, etc. as nothing more thanmuscles flexing, limbs changing position in space, and so forth.  We are to see them, in other words, as essentially just more complex instances of the kind of movements we see in a weather vane, a piston, a boulder rolling down a hill, billiard balls knocking into one another, etc.   And then we are to redefine “thinking” and other mental activity as nothing more than such de-mentalized bodily motions.  To learn to see all human behavior this way would just be to learn to see it as no more meaningful or reflective of mentality in the usual sense than the motions of billiard balls, boulders, pistons, etc. is.  It would be to learn to see in it “thought” only as redefined -- as an especially complicated series of motions or tendencies toward motions. 

Hence the bizarre suggestion that all thought is really just the “incipient twitching of muscles.”  A natural retort to this claim would be that it entails that someone pop dancing, or even just having a seizure, must be engaged in very deep thought indeed.  Of course the reductionist will respond by defining thought in terms of the specific kindsof motions we usually associate with thought -- making such-and-such marks on paper, rubbing one’s chin, etc.  But this is no more plausible than reducing sentence meaning to certain specific kinds of shapes. 

Wittgenstein is sometimes misunderstood as a kind of reductive behaviorist because while he is very keen to avoid the sort of reductionism associated with Watson and others, he does not have the metaphysics necessary to make it clear exactly how behavior and mentality are related if not in a reductionist way.  The correct metaphysics is, of course, Aristotelian: In a smile, grimace, frown, or gesture, the bodily behavior is the material-cum-efficient causal side of a single action of which thought is the formal-cum-final causal side. 

As a philosophical exercise, though, or even just for laughs, it is worthwhile trying to see a sentence as just a string of marks or noises, and trying to see human thought as if it were just “body movin’.”  It can’t be done consistently, but the Beastie’s tune helps.  I prefer the album version myself, but the video is too classic not to post:

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