There has certainly been a great deal of work addressing the relationship between naturalism and the first-person perspective. Quite a number of philosophers have suggested that there are features of the first-person perspective that naturalism just cannot accommodate, whether it be qualitative character, or consciousness, or simply the ability we have to think of ourselves in a distinctively first-person manner.

I do realise that talk of natural kinds dates back to Aristotle, but I'd better not say too much about ancient philosophers lest I be convicted of practicing history of philosophy without a license.

No one worries terribly much about who the questions belong to, or whether a given contribution is really philosophy or, instead, properly nothing but science. Perhaps another way to put this is that, although I think that knowledge is a natural kind, I don't think that philosophy is.

When reflection is thereby demystified, I believe that the temptation to view human knowledge as different in kind from animal knowledge is undermined.

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.

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

When I think about discussions at the Society for Philosophy and Psychology, a group which includes not only philosophers and psychologists, but also computer scientists and linguists, it is noteworthy that one can't always tell just from the content of particular contributions from the audience, whether a given questioner is a philosopher or an empirical scientist.