Categories

Summary

The Categories is a short treatise, fifteen chapters in the Edghill translation, that asks what kinds of things we are talking about when we say anything at all. Aristotle opens not with the world but with names: a painted animal and a living one share the word 'animal' equivocally, a man and an ox share it univocally, and the grammarian takes his name derivatively from grammar. He then draws the distinction on which much of the book turns, between what is 'said of' a subject (man is said of the individual man) and what is 'present in' a subject (a particular point of grammatical knowledge is present in a mind and cannot exist apart from it). Chapter 4 gives the famous list. Every uncombined expression signifies substance, quantity, quality, relation, place, time, position, state, action or affection, and Aristotle's examples are homely: 'in the Lyceum', 'yesterday', 'shod', 'armed', 'to lance', 'to be cauterized'. Only when such terms are combined do we get statements that can be true or false. The long fifth chapter argues that the individual thing, this man or this horse, is substance in the primary sense; species and genera are 'secondary substances', and everything else is either said of primary substances or present in them. The distinctive mark of a substance is that one and the same thing can receive contraries while remaining itself: the same person is warm and later cold, good and later bad. Chapters 6 to 8 work through quantity (discrete and continuous, admitting no contrary), relation (double and half, master and slave, knowledge and the knowable, with the claim that the knowable can exist before anyone knows it), and quality, which Aristotle divides into habits and dispositions, natural capacities, affective qualities, and shape. Here he separates lasting traits from passing states: the man who blushes once from shame has been affected; the man whose complexion or temper is settled has a quality. The last chapters, traditionally called the Postpraedicamenta, sort four kinds of opposition (correlatives, contraries, privation and possession, affirmation and negation), the senses of 'prior' and 'simultaneous', six kinds of motion, and the uses of 'to have'. The book matters in a classical Christian school because its vocabulary became the grammar of later thought. Through Porphyry's Isagoge and Boethius' Latin translation, the words substance, accident, quality and relation passed into the medieval schools, and theologians later used them, with careful qualification, in discussing the Trinity and the sacraments. Reading the Categories itself lets students meet these terms in their first, plainer setting, and it trains a useful habit: asking of any sentence what sort of thing its subject is and what kind of thing is being said of it. The library attaches the public-domain E. M. Edghill translation (Project Gutenberg #2412), whose numbered 'Parts' match the traditional fifteen chapters, so every locator in this record can be checked against the text.

Top Lessons

• The individual comes first

  Aristotle's most surprising claim, against his teacher Plato's emphasis on the Forms, is that the most real thing is the particular: this man, this horse. Species and genus are real and knowable, but they would have nowhere to exist if there were no individuals. For students the point is practical as well as metaphysical. Knowing that someone is 'a sophomore' or 'an athlete' tells us something true, but the person is more than the class; the class depends on the person, not the other way round.

• Staying oneself through change

  In Part 5 the mark of substance is that it remains numerically one while receiving contraries: warm then cold, good then bad. A colour cannot become its opposite and still be that colour, but a person can become better or worse and remain the same person. This makes moral change intelligible. Repentance, growth and decline all presuppose a subject who persists through them and to whom the change can be credited or charged.

• Habit, disposition and the shape of a character

  Part 8 separates a disposition, quickly gained and quickly lost (a chill, a passing illness), from a habit, firm and hard to displace (knowledge, justice, self-restraint). Aristotle also separates the man who blushes once from shame from the man whose complexion is settled, and the man irritable when vexed from the man of irascible temper. The distinction gives students a precise vocabulary for self-examination: a single lapse is not yet a vice, but repeated lapses can harden into one, and virtue is valued precisely because it is not easily dislodged.

• Naming things exactly

  In the discussion of relatives Aristotle insists that correlatives be 'exactly designated': the correlative of a wing is not 'bird' but 'the winged', and the correlative of a slave is not 'man' but 'master'. Where no word exists, he says it is our duty to coin one. The lesson in method is that sloppy naming produces false reasoning, and that careful thought sometimes requires new words. The chapter's own example of master and slave reflects the Greek household of its day; Aristotle uses it as a logical illustration, and students can note the assumption without letting it obscure the point about language.

Verified Quotes

Medical Lens

The Categories is a logical treatise, not a medical one, but its examples are drawn from the body and the clinic often enough to interest a historian of medicine. Lancing and cauterizing are its stock examples of action and affection; health and disease illustrate dispositions and contraries; blindness illustrates privation. Most useful for psychiatry is Part 8, where Aristotle distinguishes a passing affection (blushing from shame, irritation when vexed) from a lasting quality (an inborn temper, insanity, a complexion settled by long disease). This is an ancient analogue to the distinction between state and trait, offered by Aristotle as a point about how we speak of people; reading it as a clinical theory goes beyond the text. His remark that a man's constitution may produce a matching complexion reflects Greek ideas of bodily temperament rather than any observation the modern reader should accept as fact.

• Part 4

  'To lance' and 'to cauterize' given as examples of action, 'to be lanced' and 'to be cauterized' of affection.

• Part 8

  Habits contrasted with dispositions: knowledge is hard to displace unless some great upheaval such as disease intervenes; heat, cold, disease and health are quickly changing dispositions; health as an inborn capacity to resist unhealthy influences.

• Part 8

  Blushing from shame and pallor from fear as affections; settled complexion from constitution, long disease or sunburn as qualities; inborn insanity and irascibility as psychic qualities, passing irritation as an affection.

• Part 10

  Blindness, baldness and toothlessness as privations; change runs from possession to privation but not back, whereas the sick can become well.