It ain't in the head
By Jerry Fodor The Times Literary Supplement, October 16, 2009
Edited by Andy Ross
Consciousness Revisited: Materialism without phenomenal concepts By
Michael Tye MIT Press, 256 pages
Plato suggested that there is only one chair that is really a chair, the
Chair on which no one can sit, the One Chair that is in Heaven. This kind of
philosophical overkill, having once got started, has never stopped. Now
there is externalism.
Externalism was invented by Hilary Putnam. For
example, imagine two glasses, each of which is filled with what is, as far
as we can see, the same sort of stuff, but one is filled with H2O, the other
with XYZ. Only the H2O glass contains water. XYZ isn't water, however much
it may appear to be.
This is supposed to raise troubles in the
philosophy of mind. Just as the Putnam intuitions militate against the
semantic view that word meanings determine extensions, so too they militate
against the psychologistic view that concepts are mental representations of
extensions. If meanings, concepts, and the like are distinguished by their
extensions, then meanings, concepts, and the like "ain't in the head". Views
of meaning and concepts grounded in the Putnam intuitions are said to be
externalist.
If I read Tye right, he thinks that it's not just issues
about meaning and mental representation to which the Putnam intuitions are
germane, but also issues about consciousness and the nature of perception.
Here's a way of thinking about perception: What happens in perception is
that one makes inferences from the phenomenal content of one's perceptual
experiences to how things are in one's locality. Perceptual processes infer
from the content of one's experiences to perceptual beliefs about things in
the world. But perception doesn't feel very inferential. As Tye remarks, "it
seems natural to suppose that vision involves direct contact with external
things in standard veridical cases."
Tye is surely wrong to suggest
that an indirect-perception theorist must say that one experiences a tomato
by experiencing something else over and above the tomato. It's not part of
the indirect-perception story that, in order to infer from the experience to
the tomato, one must first infer to the experience from something else. One
doesn't infer experiences, one just has them. The mind is active in
perception but passive in experience.
Tye thinks that making sense of
things in the world being directly perceived requires supposing that such
things are part of the experiences from which perceptual beliefs arise. So
it's not just semantic stuff like the contents of beliefs and concepts that
is (partly) constituted by the external surround, so too is the phenomenal
content of experience.
Tye is in pursuit of a theory not of the
object of experience but of the phenomenal content of experience.
Inferentialist theories of perception in psychology generally take for
granted that the phenomenal content of an hallucinatory experience of the
Chrysler Building might be arbitrarily similar to the phenomenal content of
a veridical experience of the Chrysler Building. But that couldn't be true
if the Chrysler Building is a part of the former but not a part of the
latter.
Perceptual psychologists often hold that veridical perception
and misperception both require inferences from the content of experiences to
the content of beliefs, and that, in dreams, hallucinations, and the like,
the content of an experience may be arbitrarily similar to that of a
veridical experience. It's the inferences that somehow go awry. Perhaps the
psychologists have got it all wrong. But their arguments are backed by quite
a lot of explanatory success.
Tye tries very hard to make sense of
the claim that things in the world are parts of veridical experiences of
things in the world. He suggests an analogy to the doctrine that things that
a proposition is about are part of the proposition about them: John is part
of the proposition that John sneezed. But I think the analogy doesn't bear
much weight. To say that John is part of the proposition that John sneezed
is just to say that whether it's true that John sneezed depends on how
things were with John.
For Tye, the problem of consciousness is to
reconcile an exhaustively physical metaphysics with Realism about conscious
experience. There really are not just tables and chairs but also the
phenomenal contents of experiences of tables and chairs. Tye thinks that the
phenomenal content of a veridical experience includes its object.
Tye's idea is that externalism offers to reconcile materialism with the
consciousness of experience. The object of an experience is part of the
content of the experience, and the content of an experience is assumed to be
conscious content. But can we see and be conscious of things that we don't
notice? Consider a brown moth sitting on a brown limb of a brown tree. One
looks closely at the tree. Does it follow that one sees and is conscious of
the brown moth?
If Tye says yes, you do see the moth, that's bad for
him. He needs the principle that the constituents of experience are ipso
facto conscious to connect his externalism with his story about why
phenomenal content is compatible with physicalism. But if you see and are
conscious of the moth, what more is required if you're to notice it? The
moth is right before your eyes. And there's no failure of attention.
If Tye says no, you don't see the moth, that raises a question. Why does
experience that contains a moth not contribute the moth that it contains to
the perceptual belief that it causes? It looks like Tye can either have it
that the parts of one's experience are ipso facto conscious, or he can have
it that the object of an experience is ipso facto one of its parts. But it
doesn't look like he can have both.
The natural way to deal with the
moth is to say that the perceiver sees it but doesn't see it as a moth. Tye
can't say the natural thing while also holding the externalist thesis that
it's moths rather than moth-representations that experience of moths
delivers to the corresponding perceptual belief. Tye assumes that what the
experience of the moth delivers to perception is not a representation of the
moth but the moth itself.
What perceptual experience delivers to the
perceptual belief it causes is the X experienced as a such-and-such. What
the X is experienced as determines what belief is formed in consequence of
the seeing. I think externalism has outlived its usefulness.
AR Whew! It's hard work cutting Jerry Fodor down
to size. Whether he would agree that my drastic buzz cut reflects the full
glory of his convoluted thoughts is another matter, of course. Michael Tye
is the man whose style statement at
ASSC XIII I reported in June. The topic of externalism was the bone of
contention between Ted Honderich and Colin McGinn in the spat I reported in
the last chapter of my new book
Mindworlds.
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