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.

The kinds of claims I make about knowledge are thus meant to be illustrative of a general argumentative strategy which might well bear fruit in areas of philosophy which I have not thus far explored.

When I first began studying philosophy, a good deal of what went on in analytic epistemology was focused on addressing the Gettier problem. At first, I became quite caught up in it, and the kind of analytical ingenuity required for the work appealed to me. After a while, however, I started to lose interest.

Chemists in earlier centuries were quite interested in the nature of acids. They had no interest in analysing their concept of acid. After all, they knew that their understanding of acids was at a fairly primitive level, and what they wanted to do was understand something about the world better - the nature of acidity - not something about their own concepts.

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.

In my view, philosophers have shown a great deal more respect for the first-person point of view than it deserves. There's a lot of empirical work on the various psychological mechanisms by way of which the first-person point of view is produced, and, when we understand this, I believe, we can stop romanticising and mythologising the first-person perspective.

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.