The fact that we have been able to develop a successful science, which issues in ever more accurate predictions and broader explanations, is the real ground for confidence that we are in a position to gain knowledge of the world around us. At the same time, one might ask how it is that the cognitive equipment we have came about, and here, no doubt, our evolutionary origins are relevant.

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.

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.

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.

What we need to do, however, is figure out what our best available theories of the mind suggest about epistemological issues, while we recognise that we may need to change our views on these questions as new evidence comes in.

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 largely defer to the cognitive ethologists. I believe that the arguments that they make on this score are extremely persuasive. More than this, I do think as well that a priori objections by philosophers to successful research programs in the sciences have a very bad track record.