A, 4. 187ᵃ 31 — 187ᵇ 24.

This page critiques Anaxagoras' theory of the "mixture" of all things and the impossibility of infinite divisibility for organic substances.

Furthermore, if every body must become smaller when something is removed, and the quantity of flesh is defined both in magnitude and smallness, it is evident that no body will be separated out from the smallest piece of flesh; for it would be smaller than the smallest. Furthermore, in the infinite bodies there would already be infinite flesh, blood, and brain, separated from one another, yet nonetheless existing, and each would be infinite; this is irrational. The claim that they will never be separated is stated without understanding, but it is correctly stated; for the attributes are inseparable. If, therefore, colors and states had been mixed, when they are separated, there would be something white and healthy that is not anything else, nor is it predicated of a subject. So, the nous intellect is absurd in seeking impossibilities, if it wishes to separate them, while this is impossible both in terms of quantity and quality. In terms of quantity, because there is no smallest magnitude, and in terms of quality, because the attributes are inseparable. He also does not correctly grasp the coming to be of things of the same kind. For there is a way in which clay is divided into clays, and a way in which it is not. And the way is not the same as bricks coming from a house and a house from bricks, so that water and air are generated from one another.