Tuesday, September 28, 2010

Particular Beliefs and Belief-Desire Psychology

Let us suppose that Dmitri knows how to sing the "Il balen" cadenza from Verdi's Il Trovatore.

There's a debate about whether Dmitri's knowing how to sing the cadenza amounts to knowing some proposition. According to 'intellectualists', knowing how to X just is (to an approximation), knowing, for some w, that w is a way to X. I don't mean to weigh in on that debate just now, but one of the moves in it is relevant for an issue concerning imagination, which is my current research topic du jour. The move is, on its face, an argument against the thesis that knowing how is knowing that -- it argues that in some cases in which know-how is clearly present, the relevant know-that is not present, because the requisite beliefs are absent or even disbelieved. For example, Dmitri may, consistent with his knowing how to sing the cadenza, have entirely erroneous beliefs about how he does it. Maybe he thinks that he clenches his abdominal muscles, when what he really does is expand his ribcage. He thinks that he opens his mouth widely, but what he actually does is lift his soft palate. The way he sings the cadenza is by expanding his ribcage and lifting his soft palate, but he doesn't know that, because he doesn't believe it. Charles Wallace offers a version of this argument. (This was brought to my attention in a forthcoming paper by my new colleague Ephraim Glick.)

Maybe the intellectualist can offer a good response to this challenge. That's not my present concern. My present concern is this. Dmitri can sing the cadenza, and when he does, he often does so intentionally, in the manner to which an explanation in terms of belief-desire psychology is appropriate. The various things that he does in order to sing the cadenza, he does because he desires to sing the cadenza. Dmitri raises his soft palate, and he does this because he wants to sing the cadenza.

We can now talk ourselves into a puzzle, if we allow ourselves to. In order for Dmitri's desire to sing a cadenza to move him to raise his soft palate, he must have a belief linking cadenza-singing to soft-palate raising; but by hypothesis, Dmitri has no such belief. Bang! -- a puzzle.

Of course we shouldn't be too puzzled; we have lots of options. A couple come immediately to mind: maybe Dmitri does have a belief linking palate-raising to cadenzas, but not under that particular mode of presentation; maybe believing that this (demonstrating his behavior, in fact a soft-palate-raising) is a good way to sing a cadenza is sufficient for believing in such a link; maybe the action of raising the soft palate needn't be construed as deliberate and intellectual the way the puzzle presupposes; maybe we're working with far too simple a version of belief-desire psychology. There are probably more options too.

Now compare this argument from Tyler Doggett and Andy Egan, which is ultimately in the service of positing a special state of 'desire-like' imaginings. Standard theorizing in terms of belief and desire, they think, cannot explain pretense behavior.
You are imagining that you are a cat and find yourself acting this out.  (We will call behavior motivated partly by the imagination ‘pretending’ or ‘pretense-directed behavior’.)  Recall N&S’s explanation for what is going on here: ... when you pretend that you are a cat, you imagine that you are a cat and are moved by a desire to behave like a cat. In order for this desire to move you to perform any particular action, you must have some fairly specific beliefs about how cats behave.  If you want to act like a cat but know nothing about cats, you’d be at a loss.  By contrast, if you want to act like a cat and know that cats tread lightly, you’ll want to tread lightly.  Your beliefs about how cats behave, and a belief that you are imagining being a cat, combine with a desire to act in a way similar to the way you would act if what you were imagining were the case to produce pretense-directed behavior motivated by beliefs and desires.  That’s the N&S theory.

But it seems to us (and here we echo Velleman (2000)) that you do not need to have any beliefs about how something behaves (or is disposed to behave) in order to pretend that you are that thing.  You certainly needn’t have any beliefs that are sufficiently determinate to call for any specific behavior.  You can pretend that you are a cat without knowing anything about how cats behave. ...   Having (much in the line of) beliefs about how a cat behaves is no prerequisite for pretending to be a cat.

As far as I can see, the dialectic here plays out in just the same way as the puzzle indicated above. We need to explain why you bat your hand in the air. The simple view says that you desire to act like a cat, and believe that batting your hand in the air is a way of acting like a cat. D&E object that you don't have to have that belief. You might even believe the contrary. Perhaps you'd even come anew to believe that cats bat their paws in the air in that way upon finding yourself doing so in the service of your pretense to be a cat. So the simple story, according to which your behavior is produced by the belief-desire kinds of motivations familiar to non-pretense life, is inadequate.

But it's only inadequate to the extent that the simple story is also inadequate about Dmitri's cadenza, which does not involve pretense. Any of the moves that might resolve the anemic puzzle about palate-raising would apply just as well to D&E's puzzle about hand-batting. Maybe you had a tacit belief about cats batting their paws in that way. Maybe it was just a demonstrative one. Maybe we need a richer belief-desire sort of story to explain nonimaginative action; so too should we expect it to explain this action.

So Doggett and Egan's challenge for the traditional story doesn't look to me any less anemic than does the one I set up in the first half of this post.

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