Moses said to God, “Suppose I go to the Israelites and say to them, ‘The God of your fathers has sent me to you,’ and they ask me, ‘What is his name?’ Then what shall I tell them?”
God said to Moses, “I am who I am. This is what you are to say to the Israelites: ‘I am has sent me to you.’” Exodus 3:13-14
Why did God tell Moses his name is “I Am Who I Am?” No one knows completely and for sure. God’s nature is infinite; our understanding is finite. So, just like counting to infinity, we can approach an answer, but we can never expect to arrive at a full and complete one. Nevertheless, a true, partial answer is still progress from no answer at all. In this article series I offer a partial answer.
In Part 1 of this series, I introduced the philosophical tradition of natural theology, which is the study of what can be known about God by reasoning backwards from creation (nature) to the being that created it. This tradition predates Christianity, and is, I think, what Paul himself referred to in the opening to his epistle to Rome. The perhaps surprising conclusion from this is that the classical Greek and Roman world knew of God – the I Am; the Creator of Heaven and Earth – even while they were still Pagan. In this article, Part 2 of the series, I sketch how it is that they discovered God through nature, called the Argument from Motion.
On Whether God Exists – The Argument from Motion
In the natural theology tradition, there are many arguments for the existence of God. The term “argument” is not actually a combative term; this wasn’t the crux of an academic fight or “culture war” like it is today. Rather, “argument” just means a syllogism, that is, it’s a chain of reasoning anyone can follow, like an equation or deduction. While there are many such arguments for God that have been put forward, the Argument from Motion is distinguished as the oldest and most influential in philosophical history.1
The argument from motion begins with a simple, undeniable observation about nature: some things move. The term “move” here is actually a technical term which designates all kinds of change. If I walk to the kitchen and put the kettle on I moved to the kitchen, but Aristotle and co. would also say that the water in the kettle “moves” by changing from cold to hot. So, we can translate this to:
(P1) Change occurs.
Let’s unpack this premise. What Aristotle observed is that for anything to change it must be the kind of thing that can change, that is, it must have the power to change, then it must actually exercise that power.2 This is the distinction between what we now call “act” and “potency.” A potency being from the root word of our English words “power,” and “potential.” Act is from the root word of English words like “actual” or “action.”
The whole argument depends on understanding this distinction, so let’s look at an example. I am laying down; I stand up and walk to the kitchen. While I am laying down “walking” is in me only in potency. When I stand up and move my legs, walking is actualized. Notice that what is in me in potency are the powers I have but am not exercising. I am human, so I have the power to walk, eat, jump, speak, and so on, and I can do these things even if I am not currently doing them. These are potencies I can actualize. I cannot, however, fly, read minds, shoot webs from my hands, etc. These are potencies which I do not have.
With this distinction we can add the second premise:
(P2) Every change is the actualization of a potency.
I’ll also give you premise three:
(P3) Potencies can only be actualized by something that is already actual.
Why should we believe this premise? Well… because it is obvious. My walking is actualized by the movement of my actual legs not my potential legs. A human with only potential legs (a fetus perhaps) cannot walk.3
Putting these three premises together leads to the following conclusion:
(P4) Therefore, every change entails something actual to actualize it.
So, I have proven that in order to actually walk I need to have actual legs. This is hardly a monumental discovery of philosophy! But notice that we still have not explained my moving to the kitchen. My walking is caused not by my legs (that only explains the potential to walk), but by the movement of my legs. We have only exchanged one movement for another (or one change for another). Ultimately, the movement of my legs will need to be explained by something else actual, perhaps the chemical processes of my muscles, which is just another instance of change! Now we have a regress. This regress can only terminate with something that can change other things without itself changing in the process.4 In other words, an unmoved mover, or unchanged changer. Without a being like this existing, change cannot happen. Of course, change does happen, so an unmoved mover must exist.
So, we’ve proven the existence of an unmoved mover. Is the unmoved mover God? The simple answer is yes, it is. Once we understand what kind of thing an unmoved mover must be we’ll see that it is what everyone understands to be God, the I Am. However, that part of the argument must wait for part 3 of this series.
To finish off this this article I want to consider a common objection to the part of the argument from motion we’ve seen so far. The objection is this, I’ve said that to terminate the regress of moved movers we need an unmoved mover, but couldn’t it just be that there is no end? What if its just moved movers for infinity? Why does the chain need to end at all?
Perhaps an infinite chain of causes is possible (I don’t really know). However, if it is possible, we can be certain that it isn’t possible for this particular chain of causes. This is because what needs to be explained isn’t each instance of motion in the chain, but the entire presence of motion in the entire chain.
To illustrate this, suppose you see an illuminated lamp, but it seems to have no cord. You will be puzzled. Lamps have the potential to make light only if actualized by electricity. You investigate the lamp to see if it has batteries. It does, and you are satisfied, because batteries are a source of electricity. Suppose now that there were no batteries. Then there must be a cord that is hidden from view. You find a cord, but this is still not enough. Cords carry electricity, they do not generate it. You follow the cord to an outlet and are satisfied. But why? Outlets are themselves just cords. Suppose someone said that the copper wire in the outlet went on for infinity and never connected to a generator, would that explain the light in your lamp? No. Because what needs to be explained is not the chain that passes electricity to the lamp, but the presence of electricity itself, and that will only be explained by something which can generate electricity. It’s the same with change/motion. An infinite regress of moved movers is like an infinite line of copper wire. It needs to terminate in a source which explains the presence of actuality in the chain, ie. we need something which can generate actuality.
Check back next month for the final part of this series where we will explore how an understanding of the concept of an unmoved mover sheds light on God’s name, the I Am.
1 In Thomas Aquinas’s famous five ways, the Argument from Motion is the first, because it is, in his words, “the most manifest” by which he meant the most evident or obvious. Aquinas did not invent the argument, but rather inherited it from Aristotle, the genius Athenian philosopher and tutor to Alexander the Great. But Aristotle did not invent it either. He no doubt learned it from Plato, his own teacher, who is the closest we can get to a true originator of the argument, however, its form of arguing back to a single, ultimate explanation predates even him and is likely what animated much of pre-Socratic philosophy (see God and Greek Philosophy by Lloyd Gerson). All of this is to say, that the argument from motion is practically as old as western philosophy itself, it is a landmark at the very beginning of recorded inquiry.
2 Every instance of change is defined by this general formula: x changes into y if and only if x could be y, and x becomes y. In technical jargon, if x could be y, we say that x is potentially y, or, x has y in potency (notice the root word potency means both “power” and “possibility;” this is important). When x becomes y we say in technical jargon that y becomes actual, that y is actualized, or, that x has y in act.
3 No one I know of challenges (P3), but I will give a defense of it all the same because it is helpful for understanding a move in the argument further on. Act and potency are more than just the mechanisms of change, they are also modes of existing. Altogether, there are three ways one can relate to existence. First, one can “not-exist,” and then, of course, one can “exist.” In between these two is the intermediate of “potentially exist.” If we do not allow this intermediate we run into all sorts of metaphysical problems which I will not go into. The material point here is that potencies cannot actualize anything because they do not fully exist. They are on their way to existing but have not arrived.
4 To see this, suppose the actualization of A is caused by B. We know that A is something that is a mix of potency and act. It is actual enough to be acted on, but potential enough to change. What about B? There are three options: (i) B is pure potential, with no act; (ii) B is a mix of potency and act; or (iii) B is pure act, with no potential. Now we have already ruled out (i), since something that is pure potential cannot cause anything. If it is (ii) then we have only replaced one motion for another and punted the problem. The only option remaining is (iii), that there exists something that is pure act which that can actualize potencies without itself being actualized by anything.