Praedicamenta

The Categories (Greek Κατηγορίαι Katēgoriai; Latin Categoriae) is a text from Aristotle's Organon that enumerates all the possible kinds of things that can be the subject or the predicate of a proposition. They are "perhaps the single most heavily discussed of all Aristotelian notions". The work is brief enough to be divided, not into books as is usual with Aristotle's works, but into fifteen chapters.

The Categories places every object of human apprehension under one of ten categories (known to medieval writers as the Latin term praedicamenta). Aristotle intended them to enumerate everything that can be expressed without composition or structure, thus anything that can be either the subject or the predicate of a proposition.

The text begins with an explication of what is meant by "synonymous," or words, what is meant by "homonymous," or words, and what is meant by "paronymous," or (sometimes translated "derivative") words.

It then divides forms of speech as being:

Only composite forms of speech can be true or false.

Next, he distinguishes between what is said "of" a subject and what is "in" a subject. What is said "of" a subject describes the kind of thing that it is as a whole, answering the question "what is it?" What is said to be "in" a subject is a predicate that does not describe it as a whole but cannot exist without the subject, such as the shape of something. The latter has come to be known as inherence.

Of all the things that exist,

Then we come to the categories themselves, whose definitions depend upon these four forms of predication. Aristotle's own text in Ackrill's standard English version is:

Of things said without any combination, each signifies either substance or quantity or qualification or a relative or where or when or being-in-a-position or having or doing or being-affected. To give a rough idea, examples of substance are man, horse; of quantity: four-foot, five-foot; of qualification: white, grammatical; of a relative: double, half, larger; of where: in the Lyceum, in the market-place; of when: yesterday, last-year; of being-in-a-position: is-lying, is-sitting; of having: has-shoes-on, has-armour-on; of doing: cutting, burning; of being-affected: being-cut, being-burned. (1b25-2a4)

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