Categories

1. Three important systems of categories: Aristotle

No account of categories would be complete without mentioning Aristotle, who not only introduced the notion into Western philosophical discussion, but also authored a work called The Categories in which he presents the following list of categories: (1) substance, (2) quantity, (3) quality, (4) a relative, (5) where, (6) when, (7) being in a position, (8) having, (9) acting upon, and (10) being affected.

How Aristotle arrived at precisely this list of categories is not entirely clear. He might have done so by considering what questions could be asked about things that could only be answered by one kind of reply. ‘What is it?’ requires a reply that specifies a substance, ‘How much?’ requires that a quantity is given, and so forth (Ackrill 1963).

An alternative suggestion is that Aristotle derived his list from reflecting on the structure of Greek grammar, with substances as the worldly equivalent of nouns, while quantity, quality, and relation were picked out by different kinds of predicates (Baumer 1993). Whatever it might have been (and the approaches just mentioned are certainly not exhaustive), it is clear that the Aristotelian categories are categories of things. Language might have provided a starting point for determining what the categories are, but this does not imply that the categories themselves are linguistic or conceptual. They form part of the external world, and are not confined to linguistic representation. Nevertheless, Aristotle must obviously have assumed there to be a close linkage between the language we use to talk about things, and the things talked about. If the two did not exhibit a common structure it would be very hard to justify how any reflection on language or other ways of representing the world could ever yield any insight into the structure of the world represented.