Book 12
8
Again, Plato at least cannot even explain what it is that he sometimes thinks to be the source of motion, i.e., that which moves itself; for according to him the soul is posterior to motion and coeval with the sensible universe.Aristotle refers to Plato’s rather inconsistent account in Plat. Tim. 30-34. Now to suppose that potentiality is prior to actuality is in one sense right and in another wrong; we have explainedThe reference is probably to 5 above, but cf. Aristot. Met. 9.8. the distinction.
9
But that actuality is prior is testified by Anaxagoras (since mind is actuality), and by Empedocles with his theory of Love and Strife, and by those who hold that motion is eternal, e.g. Leucippus.
9
Therefore Chaos or Night did not endure for an unlimited time, but the same things have always existed, either passing through a cycle or in accordance with some other principle—that is, if actuality is prior to potentiality.
