PROBLEMS OF THE FIRST CAUSE
Fr. William Most
1. Aristotle said that if I am at one point on the earth and want to travel to another, there must first be the capacity. If the trip comes off, that capacity is filled or fulfilled. He liked the words potency and act. We notice soon that this same pattern of capacity or potency and act or fulfillment comes up not only in traveling, but in any change.
Before the change, there is a capacity, which involves some emptiness or privation which would like to be filled. If the change goes through, that capacity is filled or fulfilled. So there is a rise. New being appears.
If I am causing a change, where did I get the extra being? Perhaps I had it in stock somewhere in me. But if so: How did that part of me in the first place get up from capacity or potency to act? It at least had to get from capacity for existence up to existence. So, where did it get the added being? It cannot give itself what it does not have. So we look for an outside source. If every source we look at has the same problem of getting up, of getting the added being, we have not solved the problem. We must then come to a cause that has no problem of getting up to actuality, it simply is actuality, pure actuality.
Such a being will be infinite. For potency is not only capacity but limit, e.g., if I have 3 glasses, 4, 8 and 12 oz. each an holds so much liquid, but it also sets a limit. So a being with no potency, has no limit. So without limit, it is infinite. There is not room for two infinitesthey would coincide, so there is only one infinite. It is also outside of time, for time involves constant changea being without potency cannot change.
But A had a trouble. He knew there has to be a First Cause, which cannot change, having no potency. But the chain of causes we pictured is efficient.
Yet A could not think of any efficient cause that would not change in the process of causing change. Even if it could cause change by willing changeone moment it would be at rest, not causing change, the next moment causing it. So A said the First Cause must be a final cause. But that derails the whole train of thought and causes.
We solve it: God can cause change by willing it, but His acts of will, since He is unchanging, are always there, they are eternal. He is identified with His acts of will. So the first cause is an efficient cause.
2. In this way we see that there can be no infinite regress. For if I am causing the change, as was said above, there is the problem: Where did I get the extra being that fills up the potency that was a least partly empty before the change? Perhaps I had that extra on hand within me somewhere. But even if I did, I must ask: Where did that part of me get the added being to rise from potency to act?So I look outside me for a source, but if every source I consider also has the problem of getting extra being to rise from potency to act, there is no solution to the problem until I reach a being that does not have to get up to act, it simply is pure act, the first cause. If I imagine a chain of causes before that, the same problem exists in regard to each of them no matter how long the chain is. So we must reach that Cause that does not have to get up, it simply is up, that is, it is Pure Actuality.
3. Similarly, we see why everything but the Pure Act needs a cause: everything else has to get up from potential existence to actual existence, it needs added being for that, which must come from the First Cause. The reason why the First Cause does not have to have a cause is simply that it is Pure Actuality, as we proved above, and so needs nothing to actualize a potency for existence; It simply is pure act.
4. All other things do not have to existtheir potency for existence might not be filled. It is filled only if the First Cause fills it or actualizes it.
So there is only one Being that has to exist, i.e., whose existence is necessary, for without it nothing else would exist, would rise from potential to actual existence.