SEP — Aristotle

The Stanford Encyclopedia of Philosophy’s general entry on aristotle; first published 25 September 2008, substantively revised 25 August 2020. T1, same class as sep-epistemology and sep-plato. Note the revision gap: this one is six years older than the Plato entry.

What it establishes

• The life. 384–322 BCE. Born at Stagira in Macedonia; about twenty years at Plato‘s Academy in Athens; research in Asia Minor; tutor to the young Alexander around 343 BCE; back in Athens in 335 BCE to found the Lyceum, where he taught thirteen years before retiring to Chalcis.
• The corpus. Roughly 200 treatises, of which about 31 survive, and they read as lecture notes rather than finished books. The division is threefold — theoretical sciences (metaphysics, physics, natural philosophy), practical (ethics, politics), productive (rhetoric, poetics, crafts) — with logic set apart as the Organon, the tool used by all of them rather than a subject among them.
• Syllogistic. He “developed the first formalized system of logic and valid inference,” built so that every deduction reduces to forms whose validity can be seen directly.
• The four causes. Explaining a thing means giving its material, formal, efficient and final cause — what it is made of, its structure, what produced it, what it is for.
• Hylomorphism. “Ordinary objects are composites of matter and form,” with potentiality and actuality describing how a thing moves between them.
• Eudaimonia. The practical sciences ask how a human life goes well, and under what conditions.

Against his teacher

Aristotle attacks the theory of forms at the point of univocity — the assumption that a term like “good” names one unchanging essence wherever it is used. His replacement is core-dependent homonymy: a concept can be genuinely multivocal and still hold together, because its several senses depend on one primary sense.

This is the tradition’s first structural argument about meaning, and it is a live position, not a historical curiosity — it is what lets you deny that “good” is one property without conceding that ethics is talking about nothing.