I have made some headway in addressing these questions, however, and succeeded in explaining how it is that the category of knowledge might play an important role in empirical theories. To the extent that talk of knowledge can be shown to play an explanatory role in such theories, the analogy I wish to make with paradigm natural kinds such as acids and aluminum starts to make a good deal of sense. This is, of course, connected with the issue of the role of intuitions in philosophy.
No one would suggest that we can adequately investigate what makes something an acid, or what makes something aluminum, by bringing our pretheoretical intuitions about these things into reflective equilibrium by way of armchair theorising.
In my view, since the case can be made that knowledge too is a natural kind, the role of pretheoretical intuitions is similarly diminished in epistemology.
Bealer has a number of reasons for thinking that a naturalistic epistemology is self-undermining. Let me focus on one of these. (I've tried to take on all of them in the first chapter of Knowledge and Its Place in Nature.)
Bealer argues that the kind of naturalistic view which Quine holds will rob him of the ability to make the normative claims which (many) naturalists wish to make in epistemology. I don't think this is right about Quine, but I'm certain it's not right about my own view. To the extent that I can show that talk of knowledge is firmly rooted within empirical theories where it plays an important explanatory role, I thereby demonstrate its naturalistic credentials.
What I argue is that talk of knowledge plays an important role in theories within cognitive ethology. The idea is this. First, one sees cognitive ethologists arguing that we need to attribute propositional attitudes to some animals in order to explain the sophistication of their cognitive achievements.
Talk of belief in these animals is not some kind of anthropomorphism. We simply cannot explain the kinds of problem solving and behavioral sophistication some species exhibit without supposing that they have genuine beliefs. But once these ethologists finish making the case for animal belief, they quickly move to talk of animal knowledge as well. What I argue is that this is not a mere façon de parler.
Rather, although belief may be adequate for explaining the behavior of individual animals - an animal which believes that p will behave no differently from an animal which knows that p - talk of knowledge is necessary once one begins to look at explaining the cognitive capacities of a species.
The various processes of belief acquisition which are native to a species include ones which may allow for the reliable pick-up of information, which, in turn, allows individual members of the species to successfully negotiate their environment and satisfy their various desires.
Ethologists thus have an interest in looking at these capacities for the reliable acquisition of belief, and it is not surprising that they have a name for the true beliefs which are the typical product of these reliable capacities. They call them items of knowledge. So I argue that talk of knowledge may thereby be seen to be embedded within a successful empirical theory.
So I do, of course, reject much that is central not only to the psychology of Descartes and Kant, but to their epistemology as well. No doubt, the best available theories of today will look primitive in comparison with what we are in a position to understand hundreds of years from now.