Theism Debate Opening Statement

I have a small debate on the existence of God coming up with one of the philosophy professors at LBCC for our Philosophy Club. It's short, and only an hour, so, my statement is about ten minutes. Nothing original, just what Edward Feser has been saying for a while. I figure it might be a good idea just to put up here for future reference. Prayers appreciated for my debate coming up Thursday! 

The argument I’ll be giving for the existence of God is the first which St. Thomas Aquinas gave briefly in the Summa Theologica, and more in length in Summa Contra Gentiles. Change occurs. Water goes from hot to cold, from here to there, from solid to liquid, from one gallon to two, from pure to coffee, and so on. But how does change occur? This is what the ancient Greek philosopher Parmenides sought to figure out. Parmenides argued that an investigation of what change involves will demonstrate that change of any kind is impossible. For example, water that goes from hot to cold. At one point, the coldness of the water is non-existent as when it is hot, and then later becomes cold and so is existent. Parmenides tells us this is problematic, for if the coldness of the water is non-existent then it is nothing, and if the coldness comes into existence then it is something. But then something came from nothing, which is impossible. Hence, Parmenides concluded, change could not occur, even in principle. 

If you think Parmenides is being nonsensical, you would be right. But what isn’t nonsensical is his argument, and Aristotle took his argument quite seriously. Aristotle argued that while it was true that the coldness of the water was not actually there while it was hot, it was there potentially, and potentiality is something, even if not actual. Change, for Aristotle, involves the actuality of some potential. Or, in scholastic jargon, Movement is the Act of Potency. 

We can now reframe the question from “How does change occur”, to “How does something go from potentiality to actuality?” Change requires something to bring the potentiality to actuality. But potentiality because it is potentiality cannot do anything. Only what is already actual can bring about this change. To change water from cold to hot requires a source of something that is already hot. To change water from hot to cold requires something that is already cold, like the air around it. To change water from one gallon to two requires another gallon. To have the water three feet in the air requires a table three feet tall. These are all examples of potentiality becoming actual by things already in that actual state. So, change requires something already in actuality by the very nature of potentiality and actuality. 

While we may think of the causes of change to be linear, this is not what Aquinas was getting at. We can trace back the causes of the water being from hot to cold because we put fire under it, and we did so because we ignited the fire with some chemicals, and we did that because we were cold, and we were cold because it was snowing, and it was snowing because of the position of the Earth, and this series of causes goes back in time. But there is another series of causes, which is hierarchical, and not linear. A chandelier is ten feet from the ground. Why? Because it is held up by a chain. What holds the chain? The ceiling. The ceiling is held up by the walls, which is held up by the floor, which is held up by the foundation, which is held up by Earth. Whether the series of causes goes back in time for an infinite amount of time is simply irrelevant to whether or not a series of causes is hierarchical. Or, in scholastic jargon, this is the distinction between a series of causes ordered essentially or accidentally, per se or per accidens. In the case of the chandelier, the actualization of it being potentially ten feet from the ground derives its power from the chain attached the ceiling, etc., all of which derive its power from the Earth. To remove one link in this series of causes will nullify the actualization of the potentials that comes after it, hierarchically. What makes this series hierarchical is not that they are simultaneous, but that one is dependent on what precedes it. 

While Aquinas believed that a linear series of causes needn’t a first cause, his distinction of the hierarchical series necessitated that it needed a first cause. What is meant by first? Again, Aquinas is not talking about first in a linear, or temporal, series, rather, he is talking about a foundational first, or a primary, as when we hear the phrase “First Principles.” Because in a hierarchical series of causes, one potency is actualized by another, which is actualized by another, there must be a primary actualizer which needn’t a prior actualizer. An example that Aquinas used is a stick. A stick has no power to move on its own, even if the stick were infinitely long. So, while a series of causes have only derivative powers, there must be a power which derives from nothing else. This first cause is pure actuality.

Now then, with this distinction between hierarchical and linear series in mind, we see that the hierarchical causes are fundamental for a linear, or, per se is more fundamental by per accidens, by the very nature of the things. Take the changing temperature of the water. While we may trace back its causes back into time, we can ask the more fundamental question, why does it exist? What makes it the case that the water exists here and now? What keeps it in existence? One may appeal to the chemical makeup of water. Water exists because of the combination of hydrogen and oxygen. That does not answer the question, for the arrangement of hydrogen and oxygen is itself a potential, and hydrogen and oxygen can still come in and go out of existence and so still demands explanation, even if taken a step back in the hierarchical series. As we saw in the case of the stick and the chandelier, what this entails is that we must have first cause, or an act of existence to sustain the existence of everything else, which it itself does not derive its existence from anything else. It is pure actual existence, no potential existence. So, if there is a potential for existence in some thing that does exist, there is pure existence itself. Or in scholastic jargon, Ipsum Esse Subsistens. 

Now, because the first cause of existence is Pure Actuality, it doesn’t have actuality like water and a chandelier have actuality, but it simply is actuality, and in this case, actuality of existence. Because it is pure actuality, it could not have any potentiality, for that would be a contradiction in terms. Only things that have potentialities need explanation and causes. Something that is pure actuality and no potentiality doesn’t, by the very nature of the thing, need a cause since there is no potentiality that needs actuality. That is why we call this an uncaused cause, an unactualized actualizer, unmoved mover, or an unchangeable changer. 

Why think that this Pure Act is God? As we have seen, God is in a most fundamental sense at every single moment sustaining the existence of the world, and we generally understand God to be the ultimate cause of things. The very being of Pure Act entails other attributes traditionally belonging to God as well. It cannot undergo change, and so is immutable. Its immutability entails it is not within time, since time implies change, and so is eternal. It doesn’t come to be, or pass away, but simply is without beginning or end. Matter has potencies as well, and so Pure Act cannot be material, but rather immaterial. It cannot be imperfect or flawed because those privations are the failure to actualize some part of its nature, which is just to say it has a potentiality, which is not what Pure Act is, so it is perfect. Pure Act also has the interesting quality of being uniquely singular, that is, there could not be in principle more than one Pure Act. For there to be two of a thing, we must be able to distinguish one from the other, which is to say, there must be something one has that the other does not, that there is a perfection or privation which the other lacks, which is impossible for Pure Act. Because all powers derive their powers from Pure Act, it is omnipotent. These, and others, are key features of what God is, and what Pure Act is. 

To recap, we observed that change occurs. This showed that there is a distinction between actuality and potentiality. Then we saw that in whatever changes, that potentiality can only go to actuality by something else that is actual. Then we made a further distinction between a series of caused that is linear and hierarchical and that a hierarchical series of causes cannot extend on forever. This means that there is a primary cause. And since existence is something that is potential for many things, we must have a thing that is pure actuality, and pure existence. This, it was shown, to be God.