Being and Change, Potency and Act

The two poles of metaphysics are Being and Change. In our daily life we see things that are, and we see them change. Yet how can change be reconciled with existence? If a thing changes it is no longer what it was. So said Heraclitus. If thing remains what it is, it cannot change. So said Parmenides.

For Heraclitus, all was change, constant flux. Being is therefore an illusion: the billiard ball that lands in the pocket is not the billiard ball that was struck, and the man who held the cue is not the man who sees the ball come to rest. There is no identity, there is no being. All is one thing, that is, nothing. The billiard ball has no identity.

For Parmenides, being was pre-eminent. Change is therefore an illusion. The billiard ball did not roll, was not struck. All that is, is One Being. The billiard ball has no identity.

Aristotle found the happy medium between these extremes. A being may have existence in actuality, and a special kind of non-existence called potency. The billiard ball is actually on the table; but in potency it is in the pocket. It is part of the billiard ball’s nature to be capable of being struck, to be capable of rolling across green felt, to be capable of coming to rest in a pocket. The ball can undergo these changes, and yet remain the same ball: it loses the actuality of being at rest on the table and gains the actuality of being at rest in the pocket, it loses the potency of being at rest in the pocket and gains the potency of being at rest on the table. The billiard ball has identity, persistence through change.


4 Responses to “Being and Change, Potency and Act”

  1. Brandon says:

    Have you read Maritain’s _An Introduction to Philosophy_? He goes through a whole series of topics in the way you do here, arguing that in each case Thomistic Aristotelianism manages to find the golden mean between two extremes. A very interesting book, actually.

  2. Will says:

    You caught me! I read through most of Maritain’s book a few months ago, and this weekend decided to re-read it and see what I missed the first time through. (I’m nowhere near through it yet.) But yesterday something he said clicked, and I jumped up and said, “Oh, so that’s the point of potency and act!”

    I figure, when I figure something out I need to write it down, so that I’ll remember it later.

  3. Brandon says:

    I’m much the same way; one of the valuable things about blogging.

  4. Ricky "The Hitman" Hatton says:

    Great article.

    I’m an idiot when it comes to philosophy, but I was able to understand the distinction with the way you phrased it.