Aristotle (384–322 BC)

DOI: 10.4324/9780415249126-A022-1
Version: v1,  Published online: 1998
Retrieved October 18, 2018, from

8. Change and substance

Aristotle’s Physics discusses nature, physis. The nature of x is a principle (or ‘source’; archē), internal to x, of change and stability in x; hence the inquiry into nature leads to a discussion of change in natural substances (the elements, plants and animals). Aristotle proceeds dialectically, raising and solving puzzles involved in the understanding of natural change. In solving the puzzles, he introduces the different types of beings that are presupposed by a coherent account of natural change.

In Physics I 7–8, Aristotle analyses a simple example of change – Socrates changing from being pale to being tanned. This change involves a subject (or ‘underlying thing’; hypokeimenon), Socrates, who loses one contrary (his pale colour) and acquires another contrary (his tan). Neither of the contraries persists, but the subject persists (otherwise there would not be a change in Socrates). This particular subject that persists through change is what the Categories calls a first substance. First substances differ both from second substances and from non-substances by being capable of undergoing change; they persist while receiving opposites (as Socrates is first pale and then tanned). They cannot, however, remain in existence irrespective of any properties gained or lost; Socrates’ ceasing to be a man is not a change in Socrates, but the perishing of Socrates.

The properties that a first substance cannot lose without perishing constitute (approximately) the essence of that first substance (see Essentialism). These essential properties define a kind to which the first substance belongs. A kind may be a species (eidos), for example, man or horse, or a genus (genos), for example, animal. In predicating a second substance of a first substance (as in ‘Socrates is a man’), we place the first substance in the kind it belongs to. If we predicate one of the contraries that the first substance can lose without perishing, we introduce an item (Socrates’ pale colour, his particular height, his ignorance, his being the husband of Xanthippe) in one of the non-substance categories (quality, quantity, relative, and so on). The kinds to which these non-substantial items belong are non-substantial universals.

Aristotle also examines the coming to be and perishing of a first substance. Here again, he distinguishes a persisting subject and two contraries. If we make a statue from bronze, the lump of bronze (the subject) acquires the shape of the statue, and loses the shapelessness it had, and so changes between contraries. But although the lump remains in existence, a new subject, the statue, has come into being. In this case, the subject of the change is the matter (hylē), and what it acquires is the form (eidos, also rendered ‘species’).

This analysis of change suggests an argument (Physics II 1) to show that the genuine subject, and hence the genuine substance, is the matter, whereas the apparent substance (for example, the statue) is simply matter with a certain shape. Socrates does not become another subject if he changes shape; hence (we may argue) the lump of bronze does not become another subject simply by acquiring the shape of a statue. Similarly, then, a natural organism might be understood as a piece of matter shaped in a certain way so as to embody Socrates. Natural organic ‘substances’, such as Socrates and this tree, turn out to be not genuine subjects, but mere configurations of the matter that is the real substance.

Aristotle does not endorse this eliminative attitude to natural organic substances. He uses the argument to raise a puzzle about whether matter or form is substance. He discusses this puzzle in Metaphysics VII (see §12–14). This discussion relies on his account of causation and explanation.

Citing this article:
Irwin, T.H.. Change and substance. Aristotle (384–322 BC), 1998, doi:10.4324/9780415249126-A022-1. Routledge Encyclopedia of Philosophy, Taylor and Francis,
Copyright © 1998-2018 Routledge.

Related Searches



Related Articles