Is the first way of Aquinas about scientific motion? Let’s plunge into the Deeper Waters and find out.
So many times, when I encounter atheists on the internet and they want to know why I believe in God, I ask them a simple question. I want to start with the first of the five ways of Thomas Aquinas. I don’t want to know what you think of the argument first. I just want you to tell me what the argument is.
It happened again yesterday with someone making a statement not just about what the first way was, but about all the ways of Aquinas and why they are all wrong. Again, not what I had asked for. It’s really a simple request. First, tell me what the argument is so we can make sure we’re discussing the same argument.
The number of atheists that have met this request so far is zero.
Not only that, but what they think are devastating objections are really the same ones I hear all the time and one of the most popular ones is that this is bad science. We understand motion differently now. So what’s wrong with that?
For a start, let’s look at the argument itself.
The first and more manifest way is the argument from motion. It is certain, and evident to our senses, that in the world some things are in motion. Now whatever is in motion is put in motion by another, for nothing can be in motion except it is in potentiality to that towards which it is in motion; whereas a thing moves inasmuch as it is in act. For motion is nothing else than the reduction of something from potentiality to actuality. But nothing can be reduced from potentiality to actuality, except by something in a state of actuality. Thus that which is actually hot, as fire, makes wood, which is potentially hot, to be actually hot, and thereby moves and changes it. Now it is not possible that the same thing should be at once in actuality and potentiality in the same respect, but only in different respects. For what is actually hot cannot simultaneously be potentially hot; but it is simultaneously potentially cold. It is therefore impossible that in the same respect and in the same way a thing should be both mover and moved, i.e. that it should move itself. Therefore, whatever is in motion must be put in motion by another. If that by which it is put in motion be itself put in motion, then this also must needs be put in motion by another, and that by another again. But this cannot go on to infinity, because then there would be no first mover, and, consequently, no other mover; seeing that subsequent movers move only inasmuch as they are put in motion by the first mover; as the staff moves only because it is put in motion by the hand. Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.
Aquinas tells us what motion is in this. It is the reduction of potentiality to actuality. What does that mean? Think of actuality as what is. Think of potentiality as what could be. That what could be is also not necessarily good or bad. I am sitting down right now in actuality. I have the potential to stand up and I could do so. On the other hand, I am alive in actuality right now, and I have the potential to be dead. Let’s hope that’s not any time soon.
So what is motion? Pretty much, any kind of change whatsoever.
“Okay. But the objection still seems valid. Isn’t physical change a kind of change?”
Of course, it is. The problem is that the objection acts as if that is the only kind of change Aquinas has in mind. It is not. Just my mind going from one idea to another is from potentiality to actuality. Let’s take a look at another example. Angels.
At this, an atheist can say “But angels aren’t real!”
Irrelevant question. If we are studying Aquinas’s system, we have to realize that he thought they were real. So what does he say?
Prima Pars. Question 53. Article 2.
On the contrary, If the angel be moved from one place to another, then, when he is in the term “whither,” he is no longer in motion, but is changed. But a process of changing precedes every actual change: consequently he was being moved while existing in some place. But he was not moved so long as he was in the term “whence.” Therefore, he was moved while he was in mid-space: and so it was necessary for him to pass through intervening space.
I answer that, As was observed above in the preceding article, the local motion of an angel can be continuous, and non-continuous. If it be continuous, the angel cannot pass from one extreme to another without passing through the mid-space; because, as is said by the Philosopher (Phys. v, text 22; vi, text 77), “The middle is that into which a thing which is continually moved comes, before arriving at the last into which it is moved”; because the order of first and last in continuous movement, is according to the order of the first and last in magnitude, as he says (Phys. iv, text 99).
The technical stuff doesn’t really matter at this point. What does matter is that Aquinas speaks of motion twice. He speaks of that for angels. In Q. 50 and Article 2, he quotes Dionysus to make his point.
On the contrary, Dionysius says (Div. Nom. iv): “The first creatures are understood to be as immaterial as they are incorporeal.”
Thus, motion plays to things that are not physical as well. Laws of science do not change that. We could hypothetically have a world where we were all angels and a group of holy angels and a group of fallen angels got together to discuss ultimate reality and there are somehow atheist fallen angels. The argument would still work.
This is also why science cannot touch this argument at all. As long as you have any change going on, you have the motion that is needed in the argument. Those who jump to science misunderstand the argument greatly.
In Christ,
Nick Peters
(And I affirm the virgin birth)