LOGIC while on the other hand there are signs that have no signiWcant parts These simple signs come in two diVerent kinds, names (Int 16a20–b5) and verbs (Int 16b6–25): the two are distinguished from each other, we learn, because a verb, unlike a noun, ‘signiWes time in addition’, i.e has a tense But in the Categories there is a much richer classiWcation of simple sayings In the fourth chapter of the treatise Aristotle has this to say: Each one signiWes either substance (ousia), or how big, or what sort, or in relation to something, or where, or when, or posture, or wearing, or doing, or being acted on To give a rough idea substance is e.g human, horse; how big is e.g four-feet, sixfeet; what sort is e.g white, literate; in relation to something is e.g double, half, bigger than; where is e.g in the Lyceum, in the forum; when is e.g yesterday, tomorrow, last year; posture is e.g is lying, is sitting; wearing is e.g is shod, is armed; doing is e.g cutting, burning; being acted on is e.g being cut, being burnt (4 1b25–2a4) This compressed and cryptic passage has received repeated commentary and has exercised enormous inXuence over the centuries These ten things signiWed by simple sayings are the categories that give the treatise its name Aristotle in this passage indicates the categories by a heterogeneous set of expressions: nouns (e.g ‘substance’), verbs (e.g ‘wearing’), and interrogatives (e.g ‘where?’ or ‘how big?’) It became customary to refer to every category by a more or less abstract noun: substance, quantity, quality, relation, place, time, posture, vesture, activity, passivity What are categories and what is Aristotle’s purpose in listing them? One thing, at least, that he is doing is listing ten diVerent kinds of expression that might appear in the predicate of a sentence about an individual subject We might say of Socrates, for example, that he was a man, that he was Wve feet tall, that he was wise, that he was older than Plato, and that he lived in Athens in the Wfth century bc On a particular occasion his friends might have said of him that he was sitting, wearing a cloak, cutting a piece of cloth, and being warmed by the sun Obviously, the teaching of the Categories makes room for a variety of statements much richer than the regimented propositions of the Prior Analytics The text makes clear, however, that Aristotle is not only classifying expressions, pieces of language He saw himself as making a classiWcation of extra-linguistic entities, things signiWed as opposed to the signs that signify them In Chapter we shall explore the metaphysical implications of the doctrine of the categories But one question must be addressed 125