For one thing, I think that there are questions which philosophers raise which, although science bears on them, are not typically the central focus of those who work in the sciences. At the same time, I don't have a view of philosophy which marks it out as different in kind from scientific work

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.)

The kind of approach I take is different from much of experimental philosophy. Although the experimental philosophers and I are certainly in agreement about the relevance of empirical work to philosophy, a good deal of their work is devoted to understanding features of our folk concepts, and in this respect, at least, I see them as making the same mistake as those armchair philosophers who are interested in conceptual analysis.

I do agree with Stich that a quick move from our evolutionary origins to the reliability of our cognitive mechanisms is not legitimate. As I see it, the case for the reliability or unreliability of various cognitive mechanisms lies elsewhere.

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.

Externalists reject any such view. I think that the idea that we can tell, simply by way of reflection, whether our beliefs are justified, is deeply commonsensical. More than that, the idea that responsible epistemic agents ought to reflect on their beliefs, and hold them only if they somehow pass muster, is utterly natural.

It started becoming clear to me how one might have views about the nature of mind and of knowledge which are empirically informed. This way of thinking about philosophical theorizing makes sense of how philosophy might be a legitimate intellectual activity, in a way that a good deal of the armchair philosophy, I believe, cannot.