ABSTRACT
I have said more than once already that, as I understand the matter, to have the concept of X is to know what it is for something to be X, and that this can be a matter of degree since one can have knowledge of some aspects of X without necessarily knowing others. To have a concept of X is to believe something about what it is for something to be X, and this belief may or may not be right. To the extent that we can speak of the correct or right understanding of something, we can speak of the concept of that thing, and the concept is therefore objective and shareable with others. Belief presupposes knowledge to the extent that one must know what it is that one is believing about and what it is for something to be what that thing is believed to be. 1 Thus it seems to follow that one cannot have a concept of something unless one has the concept of something or other (though not necessarily of that of which one has a concept). A subjective understanding presupposes participation in a public and objective understanding at some point; it is in this sense that it presupposes knowledge. Thus my claim that perception involves having concepts entails that perception presupposes knowledge in a logical, though not necessarily temporal, sense of 'presuppose'. Something cannot properly be said to see X unless it has knowledge of something in terms of which X is seen (though that knowledge does not have to be knowledge of X as such). That does not, however, entail that the knowledge has to precede the perception in time; they may, for example, come together. Nevertheless it does entail that a creature cannot properly be said to perceive things unless it is capable of having relevant knowledge, and this applies to animals and infants (i.e. non-language-users), as well as to mature, adult human beings. I shall begin my consideration of concepts and their conditions by discussing the attribution of concepts to animals, as the case of animals raises certain issues in a particularly acute form; the considerations to be derived from this can then be applied to the case of infants and thereby to developmental issues generally.
