The Existence of God: The Argument From Motion

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I’ve been tempted to write a full synopsis of a cosmological argument that not only demonstrates the existence of something such as an Unmoved Mover but also demonstrates that the Unmoved Mover must be unique, immutable, eternal, perfectly good, omnipotent, and omniscient for some time. However, I’ve until now never felt confident in my ability to make that a reality (and I still have my doubts). I have typed up everything below myself, though I am heavily indebted to Edward Feser’s book Five Proofs Of The Existence Of God to making this possible. There are a handful of borrowed phrases, and in the second half I followed Feser’s argument more closely (and in a much more abbreviated fashion), but I have not just copied and pasted paragraphs from his book. This is something I put together, not me copying verbatim from another work for anyone to read. If this was to be published I would of course need to put proper citations in, but this is an informal argument being made on a social message board, so I believe I’m okay. At the end of the argument I will also address some common objections. Without further ado, let’s begin.

The Argument From Motion

Our everyday experience shows us that things change. An ice cube at room temperature will melt. A rubber ball will melt when heat is applied to it. Our experience also shows that the objects of change do not move (or change) themselves. Ice does not make itself melt into water. Rather, the heat in the air causes the ice cube to heat and melt. Likewise, a rubber ball does not melt on its own, but melts when an external heat source is applied to it.

[This remains true when the concept of heat is analyzed on a more technical level. Heat is the average kinetic energy in a system. The molecules are moving around, and the more average kinetic energy there is the hotter the system is. When a group of molecules with a higher average kinetic energy make contact with a group of molecules with a lower kinetic energy, energy is transferred from one grouping to the other, such that the average kinetic energy evens out over time (assuming a closed system and no other external causes).]

So the actual rubber ball in front of me has the potential to be melted into rubber goo, such that there can be actual rubber goo. A heat source applied to a rubber ball makes actual the potential for that material to be a rubber goo. The potential for rubber goo cannot actualize itself. It must be made actual by an external cause. Furthermore, no potential can actualize itself. Whatever goes from potential to actuality must have a cause (1). This is the Principle of Causality.

Let me present two types of causal series. The first is a linear series. A father begets a son, who begets a son, who begets a son. In this sense, a father is a cause of his son. The grandfather and great-grandfather are also causes. Such a series can continue in an infinite regress without any logical contradictions. If the great-grandfather, grandfather, and father die, it does not affect the son’s own causal power to beget another son or to continue other actions.


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The second type of series is an hierarchical series. We will get more technical, but as an illustration consider a chandelier suspended from a ceiling by a chain of steel links. The chandelier is dependent on the first link it is attached to to be suspended from the ceiling. That link is dependent on the next link in the chain, which is dependent on the next link, and so on, until we reach the link that is firmly attached to the ceiling itself. Unlike in the linear series, the chandelier-being-suspended-from-the-ceiling is continuously dependent on each and every link in the chain for being suspended from the ceiling. The removal of any one link from the chain eliminates the causal power of all links below it to cause the chandelier to be suspended from the ceiling, and the ceiling itself is from where all causal power to be suspended from the ceiling originates.

[Yes, we could of course go on to the walls that hold the ceiling up, and then to the foundation the walls are on, and the Earth upon which the foundation rests, and so on. That would certainly be true. We will get there. Please indulge me a little longer for the purposes of the illustration.]

It should be clear that if the ceiling were removed from this example, the chandelier could not be suspended. Adding additional links to the chain, even to infinity, would do nothing to actually raise the chandelier off the ground. The links do not have this capacity innately, the capacity is derived from the ceiling, and an infinite number of links, whether straight or in a circle, does not suspend the chandelier. Neither can causal power be imparted by the ceiling and then the ceiling removed, for the chain link’s causal power isn’t derived just once for all, but is totally dependent upon the ceiling for each and every moment it is suspended. Therefore, it is nonsensical to propose that an infinite regress of links without a ceiling can possibly cause the chandelier to be suspended. It is not a question of when the chandelier was hung up some time in the past and who or what did it (that would be a linear series question), but about the continued necessary presence of the ceiling for the potential of the chandelier to be suspended to be actualized in any given moment at all.

An hierarchical series can be expressed logically in the following format:

A is being caused to G by [B inasmuch as it is being caused to G by (C inasmuch as it is being caused to G by {M})].

To get to the heart of the issue, it must be asked what makes any one of these chain links exist in the first place? There is nothing inherently necessary about any one link that requires it to exist as opposed to a different link existing or not existing at all. I am not asking who or what manufactured the link, but about why it exists right now in this very moment. The existence (or actuality) of this steel link is something that only need potentially be.

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One could reply that the steel link exists because the iron and carbon atoms that make it up, along with some other elements, exist, but we encounter the same problem here. There is nothing inherently necessary about any one iron atom’s existence as opposed to a different iron atom or no iron atom at all (one less iron atom in the universe). I could go on to say that the iron atom exists because the protons, neutrons, and electrons that make it up exist. But we have the same issue again. We have a proton because the up and down quarks are present. There seems to be nothing here in this series that isn’t just something that could have potentially not been, therefore it does not seem we have explained why the existence of any is being actualized.

It should be clear that this is an hierarchical series and not a linear series, because if I remove any one member in this series I would not have the same existent object I did before. If it was a linear series, removing any member would not impact members later down the chain, and that is not the case. It should also be clear that going back in time, even to the origin of the universe, even going backwards for infinite time does not resolve the question, because we are not interested in who or what molded this piece of material, but why it exists right now when it has no intrinsic reason to continue to exist(2).

By logical necessity, there must be a cause to this series which is actual without itself being caused to exist, otherwise we would have nothing at all. If this hypothetical member with non-derivative existence were caused by anything else, we run again into the problem of an infinite regress and no explanation for the series to be at all. So there must be an “Unmoved Mover” to this series. One that is actual without being moved from potential to actuality by something else.

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We’ve established that the existence of things that only potentially exist must be actualized, and furthermore that this requires the existence of at least one being that is just inherently actual. Such a member is called an Unmoved Mover. Is it possible for an Unmoved Mover to have potentiality? Is it possible to have its existence in a non-derived way but to have the capacity to change?

Consider a being that exists in a non-derived way with a potential that was not previously actualized that must be actualized by something else. That means that some manner of existence for this being was not already actualized, and if this must be actualized by something else, then it is evident that this being was never an Unmoved Mover and its actualized existence is caused by something else. Therefore the Unmoved Mover must be purely actual without any potency that can be actualized.

If the Unmoved Mover has no potency that can be actualized and simply is actual, that is to say that it does not undergo change. The unmoved mover must therefore be immutable.

Since time is a measurement of change, and since the Unmoved Mover does not change, it exists without having a beginning (for to come into being would mean it is not inherently necessary but was actualized by something else) and without ever having an end, it is not subject to any progression of time. Therefore, it is eternal.

To be material is to be subject to change and subject to time, for material can be affected, moved, changed, and tend towards corruption (have a possibility of going out of being). Therefore it must be immaterial.

If an Unmoved Mover was not perfect, it would have some defect of some sort, a privation in its actuality, the failure to realize some potential inherent in a thing, a potential which could be actualized. But it’s been established that the Unmoved Mover must be pure act without any capacity for potency, therefore it must be perfect (meaning without potency, defect, privation).

If the Unmoved Mover were not unique, multiple instances of the Unmoved Mover would have to be differentiated from each other. But it’s been established that the Unmoved Mover is immaterial, and therefore cannot be distinguished by its material or position in space. It is eternal which means it cannot be distinguished by time. It is perfect meaning that it can’t be distinguished by having some perfection (or in reverse, some privation) that the other lacks. There is no way in principle for multiple instances of an Unmoved Mover to be distinct or differentiated. By the law of identity, the Unmoved Mover must therefore have unity, be one, and be unique.

There is only one Unmoved Mover, and all other things that exist or could exist have existence in a derivative way. It is only the Unmoved Mover that has the non-derivative causal power to cause all things other than itself to exist. It is the source of all actualizing power, all possible power. That is what it means to be omnipotent.

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Consider also that a thing is good insofar as it actualizes the potentials inherent in the thing it is. A good triangle is one that better approximates a closed polygon with three perfectly straight sides. A bad triangle is one that does not. A good golfer is one that has better mastery of the game of golf, while a bad golfer has little talent at it. The Unmoved Mover has been established to be without potency, perfectly actual. It has no deficiencies or privations. Therefore, it is perfectly good.

So far we’ve established that the Unmoved Mover immutable, eternal, immaterial, perfect, omnipotent, and perfectly good. Next we will demonstrate that it must be omniscient.

One way to reason to the Unmoved Mover’s intelligence and omniscience is by the principle of proportionate causality (PPC). What is present in an effect must be present in the total cause (all sets of factors) that brought it about. As an illustration, suppose I give you twenty dollars. The effect is you having twenty dollars. In order to do so, I must have the causal power to bring about that state of affairs.

What will come to mind first for most people is having this causal power formally. If I have twenty dollars in my wallet, I can give you it in cash. I have the form of having $20, and I give you the form of having $20. Another way the effect can be in the cause is virtually. I might not have $20 on hand, but I may have $20 in the bank. By writing you a check, the total set of causal factors (me and the bank) can bring about the effect of you having $20. The final way the effect can be in the cause is eminently. Maybe I don’t have $20, but I have legitimate access to a federal reserve printing press and can have a $20 printed specifically for you. In this way, through myself and the printing press, I have the power to bring about the effect eminently.

We’ve already reasoned that the Unmoved Mover is immutable, eternal, immaterial, perfect, omnipotent, and perfectly good. We know that the effects and possible effects (actual existent things) must be in the Unmoved Mover by the PPC. That they are in the cause formally is ruled out by virtue of it not being material, not occupying space, being one, and being simple. It therefore can’t be composed of millions of different actual trees and human beings and atoms. Therefore the effects must exist in the cause either virtually or eminently. That is, the causal power for all things that have been caused and can be caused exist in it in a real but abstract way. Furthermore, all possible relationships between things must also exist virtually in it. They must exist and can only exist in the Unmoved Mover in a universal and abstract way. But this is most closely analogous with the capacity to have concepts and relationships between concepts as thoughts in a mind, as knowledge. Therefore, the Unmoved Mover is something analogous to a mind or an intelligence that has (or is) knowledge. And if it has knowledge of all things and relationships between things that have been, are, or can be, it is what we call omniscient.

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One might object that we do not have rational grounds to assume the principle of proportionate causality to be true. However, the PPC is implicitly taken for granted in the scientific method. If the PPC were not true, then we could not in principle trust the use of control groups or test groups, in which we attempt to eliminate interfering causes. For if the PPC were not true, then we would have to accept that the observable results might have portions that are completely inexplicable and therefore not representative of the conditions and causes we are trying to observe. Let me be clear, I don’t mean unkown factors or things beyond our current ability (or possible ability) to control. It would mean that the effects are, in part, completely uncaused. Furthermore, it’s taken for granted with our perceptions for the same reason. If the PPC were not true, then our perceptions cannot be said to reliably track reality, as they could all be partly or totally uncaused. Let me be clear here, it’s evident that some people’s perceptions do not track reality well, but that is explicable due to limitations of the physical matter of the brain, bad wiring in the brain, etc… the total factors (causes) for their perceptions are explicable according to the PPC, even if we cannot know all the factors. If the PPC were false, it means that our perceptions in principle are possibly on some level without cause. Furthermore, consider logical arguments. We generally take logic and reason as the cause for whether we come to a particular conclusion. Some people may reason badly or differently, but this is due to other biases, experiences, knowledge, or wiring of the brain (explicable causes, whether known or unknown). To deny the PPC is to implicitly admit that our conclusions may be partly or entirely without cause altogether. Lastly, that the effects may be greater than the cause would violate the laws of of thermodynamics. To accept the PPC elsewhere but to deny its use in this case would be to commit the fallacy of special pleading. To deny the PPC, which is implicitly accepted in so many professional and academic fields, without good reason would be to beg the question against this argument (and furthermore, you’d be admitting the possibility that you have no good reason for denying the PPC if your denial is potentially not caused by any logical or biological factors). Therefore, we have solid grounds to accept the PPC as true.

So to recap, the Unmoved Mover exists and is necessary. It is immutable, eternal, immaterial, perfect, omnipotent, perfectly good, and omniscient. But this is precisely what theologians refer to when they speak of God. Therefore, God exists.

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OBJECTION 1: An animal moves itself when it walks from one place to another. Therefore the statement “no potential can actualize itself” seems false.

REPLY TO OBJECTION 1: While it can be said that an animal moves itself insofar as the animal displays a unity of being, we should also remember that the animal is composed of parts. The leg moves because the muscles in the leg contract. The muscles in the leg contract because of electrochemical signals from the nerves of the leg, which are caused by other nerve cells, which leads us back to the brain, which itself is moved by other stimuli, and so on. It can be seen that no part of the animal actualizes its own potential for movement.

OBJECTION 2: It seems a steel link is only a man made category, as are any other member in this series. We can eliminate the series by only referring to the most fundamental parts of reality.

REPLY TO OBJECTION 2: Even if we admit that a steel link is a man-made and non-real category, and also do so with the higher level groupings, and consider instead only the most fundamental parts of reality which themselves without parts, we do not resolve the issue. For it is apparent that these have no more necessity for existence than the items previously considered. They are actual, but could potentially not be.

OBJECTICTION 3: It seems to follow from the arguments that everything has a cause. But you claim God does not have a cause. That is a special pleading fallacy.

REPLY TO OBJECTION 3: The argument did not claim that everything has a cause, only that whatever goes from potential to actual must have a cause. The argument demonstrates that there must be one (and only one) being that is purely actual without any potency, that must not be actualized by anything else. There is no special pleading.

OBJECTION 4: You make an argument for theism, but you have not demonstrated that this is the God of Christianity. Therefore, your argument is false.

REPLY TO OBJECTION 4: It was not the aim of this argument to prove that Christian revelation is true, only to demonstrate that theism, and particularly monotheism, is true. You are correct that this argument does not prove Christianity, but that does not make the argument or its aim false.

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OBJECTION 5: The argument starts by assuming that change is a real feature of reality. But Einstein’s theories suggest that all of reality is one solid, four-dimensional (or higher) object. We perceive time as transient, but it may very well exist as one of many dimensions in one immutable world-block. The argument would therefore not hold if this were true.

REPLY TO OBJECTION 5: Even if the universe were unchanging it would not prove the argument false, for we’ve established that it could not actualize its own potential existence (and consider that the arrangement of the this universe could very well have been different, whether drastically or by one atom). It is not immaterial, which we’ve established that the Unmoved Mover must be. It cannot be purely actual. Further rebuttals could be given based on the arguments from composition, contingency, and the principle of sufficient reason, which have not been covered here.

OBJECTION 6: Things must be demonstrated by evidence, and there is no more reason to accept that God exists than there is to accept that unicorns exist.

REPLY TO OBJECTION 6: The argument provides good reasons for God’s existence on the basis of observed reality. Every thing in our experience is an effect we observe, and we have reasoned from those effects to the existence of God by logical necessity. There are no observable effects of unicorns that we have solid reasons for accepting, and no rational basis to accept their existence. It should also be clear that there is an ontological difference between something which is purely actual that is not actualized by anything else, and all other possible or actual things of our experience, and that unicorns, dragons, lions, humans, Zeus, Hera, and Odin cannot be the Unmoved Mover which we’ve demonstrated must exist, for all of these other things would be material in some way, changeable, not eternal, not perfectly good, not the cause of all other things, and therefore themselves must have an external cause for their existence.

OBJECTION 7: On the quantum level, it seems that some things can occur without cause. Consider radioactive decay. Therefore, the statement “whatever goes from potential to actual must have a cause” seems false.

REPLY TO OBJECTION 7: It is not universally accepted that radioactive decay and other quantum activity occurs without cause. The absence of something in a model of nature does not entail its nonexistence. Furthermore, the objection also makes assumptions about causation that we need not necessarily make. For it may just be in the nature of a particular radioactive isotope to have radioactive decay, and in that sense the efficient cause of the isotope is the cause of the radioactive decay itself. It may be easier to think of causation in terms of “ontological dependence” instead of purely mechanical reactions. Furthermore, for a cause to be sufficient to explain its effect, it is not necessary that it cause it in a deterministic way. It need only make the effect intelligible.To simply say you do not accept this view of causation or you do not accept natures would be to beg the question.

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There was a Big Bang (not actually a bang but an expansion). That’s why there is movement.

What caused the Big Bang?


The End (all else is sophistry).

Dunno. And can’t ever know.

That is a scientifically satisfying answer. Only philosophers get bent out of shape about it.

What has science got to do with metaphysics? If you don’t believe that metaphysics can provide a genuine system of knowledge then say so. But presenting a scientific theory as an explanation for a metaphysical problem, and then limiting knowledge to the scientific method alone, only succeeds in exposing your lack of understanding as regards to the epistemological methods of both metaphysics and science. It’s like yelling checkmate in a game of checkers.


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You cannot scientifically know what came before the big-bang, physically speaking. Metaphysics is dealing with a different kind of qeustion. Your attempt to deal in absolutes betrays you.

You are aware that you basically restated what I had stated, aren’t you?

Physically speaking, the concept of “before the big bang” is meaningless. There was no “before the big bang”.

And i ask you, what is that got to do with the kind of problem that Aquinas is reflecting on. It’s irrelevant if there is no before in regards to “time”.

@Bradskii @AndrewAxland @IWantGod

There’s no need to distract from the topic at hand. Not once in all eight posts was the question “What happened before the Big Bang?” raised as the question we must consider.

The only “sophistry” presented so far in this topic is in post # 9. It is fallacious in that it only begs the question. It also completely misrepresents everything that was said in the argument. I don’t know if it’s intellectual dishonesty or an incorrect assumption that he knew what he was talking about.

I was going to wait for more feedback before adding additional comments, but I wanted to interject before this becomes too sidetracked into a question that’s rather irrelevant to the line of argument. Suffice it to say that in many posts on CAF I and other theists have mentioned numerous times “it’s not about what started the universe, but about why God must be active in the here and now.” However, when challenged on that, we’d deflect and say that it would take too much explanation to get into at the time. Well, the argument presented in the topic is one such argument for what we mean.

I suppose this is the Internet and I should have expected trivial responses, but the objection received so far, from a person who I respect, is even less intellectually involved than the “if humans evolved from monkeys, why are there still monkeys?” objection. I certainly hope for some non-trivial objections at some point.


Andrew Axland is a Catholic, not an atheist.

My apologies on that. I will correct. I shouldn’t have thrown out labels in either case unless the poster clearly indicated them in their profile.

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Just wanted to say I love this @Wesrock. I appreciate your handiwork. I’m currently reading through Feser’s Scholastic Metaphysics: A Contemporary Introduction and plan to get to his Five Proofs. It’s really dense stuff, but you did a good job of concisely explaining it here. For me, the phrase “God is (or perpetually facilitates) existence” has made it far easier to understand these metaphysical arguments than when I presumed He “caused” everything and left.

A few questions:

  • Are we to believe the list of properties of God you argued for is exhaustive?
  • How would you object to the argument that nothing can cause something (as an origins of existence kind of argument)? Myself, I’d argue that the laws of nature that preceded nothing creating something, themselves, would need a cause, thus proceeding up the hierarchical chain again, but I’d like to know what you think.
  • If the unmoved mover is pure act, it must necessarily be limited to those actions which are non-contradictory (logically speaking). That is, the unmoved mover cannot end existence (remove the ceiling) because it is existence, right? Does this not refute omnipotence? Or is the unmoved mover bound by logic?

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@gregoryphealy Thanks! I have not read Scholastic Metaphysics, but I found Five Proofs to be refreshingly comprehensive.

I have not seen it claimed that this list of properties is comprehensive, nor do I think it can be. We refer to something in God that is like power, like knowledge, and like goodness. We can refer to God’s simplicity (not really brought up in my posts, but it is in other cosmological arguments). But we can’t really comprehend what it would be like to exist as God does without time, with just knowledge and not thinking, and so on. These terms are also not so much properties of God so much as analogous to what His essence is, similar but not quite capturing it. For these reasons I’d be very hesitant to label them as exhaustive.

Only something that has reality can act, and if it has reality or truth to it, it’s not nothing. It also depends upon the thrust of their arguments. Are they saying that space with a zero energy state is truly nothing? I’d disagree. Are they claiming the existence of abstract laws of nature as real universals that don’t need to be caused or have reason to exist? That’s an appeal to brute fact and I don’t believe they can coherently avoid special pleading.

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