Over at the new “Fake Barn Country”:http://blogs.brown.edu/other/philosophy/ (now with _real_ fake barns!) Jonathan Ichikawa “argues against functionalism about belief”:http://blogs.brown.edu/other/philosophy/2005/10/against_beliefdesire_functiona.html. I’m always up for defening functionalism, so I want to resist.

Here’s Jonathan’s argument.

# In general, I can’t just decide to believe _p_.
# In general, where A is the kind of thing that could be an action of mine, I can decide to do A.
# So belief can’t be explicated in terms of what actions I do.
# So functionalism is false.

The problem is all in the step from 3 to 4. (Although I’d quibble with 1 as well.) Functionalists, at least clever ones, say that there are three characteristic attributes of beliefs.

# Input states
# Internal roles
# Output states

Jonathan only focuses on the third. But beliefs aren’t constituted by what people do, but by these inputs and these internal connections as well. And since I can’t just choose what my inputs will be, or how my mental states will generate other mental states, I can’t just choose my beliefs.

Jonathan sounds like he denies the second of these, but I don’t quite understand that position. If I could just choose to, for instance, take some random _p_ to be grounds for believing _q_, then I would be (tacitly) choosing to believe _If p then q_ or _p is a reason to believe q_ or something similar. And by hypothesis that’s meant to be ruled out.

But there’s a deeper reason the functionalist should resist the step from 3 to 4. We don’t analyse belief in terms of action (since victims of paralysis can have beliefs) but in terms of dispositions to act. And as someone who has all kinds of bad habits he’d like to kick, let me tell you it isn’t just that easy to adjust your _dispositions_ to act.

For instance, I have the habit of running away when a car is bearing down on me. (This isn’t one of the bad habits – I don’t reveal that on a blog.) I couldn’t easily lose that disposition, even if I decided playing automotive chicken was one of the highest of human experiences so I seriously wanted to lose it. As far as I can tell, it’s almost exactly as easy to change these kinds of dispositions as it is to change my beliefs. In this case I really mean _exact_; the only feasible way of changing my disposition would be to form the belief (I mean the real belief, not a probabilistic version) that the cars would stop.

So these kinds of plasticity considerations that Jonathan adduces, rather than telling against functionalism, seem to me to be weak evidence in favour of functionalism.