Thursday, September 9, 2010

Higher-Order Mental Pointing

I recently re-watched the footage of the discussion from Hakwan’s actual talk at NYU. One interesting issue that came up (there were others I may talk about later) was whether a higher-order theory can avoid the mis-match problem.

The problem is this. Suppose you have a first-order state that is a seeing of red while one has a higher-order state to the effect that one is seeing green. David R. argues that the phenomenology goes with the higher-order representation and so in this case the person would have green visual phenomenology. They would be consciously seeing green. A first-order theorist will argue that the phenomenology goes with the first-order state. Block suggests this when he says that it is just the first-order state getting above a certain thresh hold that makes it phenomenally conscious. Hakwan wants to avoid this and so adopts a pointing view. On his view we have a higher-order confidence judgement to the effect that I am such and such % sure that I am in this or that sensory state. Since the higher-order state is just pointing at the first-order state Hakwan suggests that there is no mis-match problem for his view.

But the question then arises: what is mental pointing? On my view mental pointing is just having the right causal connection. That is I have a purely causal theory of reference for higher-order thoughts. However, these are complex demonstratives and have the form I AM IN THAT-RED* STATE. Where the THAT-red* term has it’s reference fixed by the causal connection between the states (sometimes I think it might be because it has the function to do so, sometime I don’t…) but the phenomenal character is determined by the conceptual content of the complex demonstrative. What are the other candidates for mental pointing? When asked later in discussion Hakwan offers the following. Suppose that each sensory state that the brain can be in is labeled 1-n. Suppose that the state labeled ’1′ has a very good signal but something goes wrong and one has a higher-order confidence judgement that the state labeled ’4′ is true then one will hallucinate 4 and fail to consciously see 1. But what are these labels if not the kind of complex demonstratives I talked about above?

Interestingly, later in the discussion, Hakwan proposes a nice empirical test that might help to decide between the higher-order view and the first-order view. The higher-order view predicts that one can have a conscious experience of green even when one has a first-order representation of red. Given what we know about the brain this might translate into having certain kinds of activity in the pre-frontal cortex that is different from the activity is V4. Suppose that we could identify, or read-out, stimulus color from the activity in V4 and we were also able to read out the color from activity in the pre-frontal cortex. Suppose that when the stimulus was unconsciously presented we say only the activity in V4 and not in the PFC. Suppose that in the Sperling-type cases we got evidence that the stimulus was represented unconsciously (activity in V4) but in the PFC we only got the read-out told us that they only saw some letters arranged in a grid. This would do what Hakwan suggests; take a prediction that no one in the world believes, do an experiment and see what happens.

I think that until we are in a position to do these kinds of experiments, or someone thinks of a clever way to get at the issue in a different way, we cannot rule the higher-order theory out. It may turn out to be false, but it may turn out to be true. Conceptual objections cannot help us as they only serve to tell us what we find intuitive.

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