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.

When we recognise that reflective processes are no more outside the causal net than unreflective processes, and that they are bound by similar constraints, we may come to understand the nature of reflection for the first time.

I was often asked how one could even make sense of this. Isn't the category of knowledge something that we project upon the world, rather than something that we discover in it?

When I got to college, I planned to be a math major, and, in addition to signing up for some math courses, I decided to take some philosophy. Quite by chance, I took a philosophy of science course in which the entire semester was devoted to reading Locke's Essay. I was hooked. For the next few semesters, I took nothing but philosophy and math courses, and it wasn't long before I realised that it was the philosophy that really moved me.

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.

I argue is that philosophers have had a tendency to present a kind of mystical view of the powers of reflection. Unreflective belief acquisition is seen in mechanistic terms, but when philosophers talk about reflection, it is as if reflective processes are not bound by the kinds of limitations which inevitably arise from being embedded within the same causal structure which governs unreflective belief acquisition.

I believe, that empirically informed approaches to the question have issued in more illuminating answers than the old armchair approaches. But I think that it would be a terrible mistake to give up on addressing normative questions in epistemology.