2 Absolutely Crucial Features That Every Strong Argument for God Must Include|Part 2 on the Nature and Existence of God


Last week, you learned about some pretty bad arguments for God’s existence.

There were a lot of reasons why those arguments do not deliver a philosophical demonstration for the existence of God.

Whether it be their subjective nature, such as with testimony…

Or its circularity, which we find in the argument that points to the Bible saying that God exists and that God wouldn’t lie…

Or maybe it’s the ontological argument which, while much more respectable, ultimately fails because it looks to the wrong starting point in its attempted demonstration…

How is it possible to demonstrate the existence of God?

Well, I’ll cut right to the chase:

Every argument for God’s existence MUST include the following:

  1. It must be a quia demonstration which reasons from effect to cause.


  2. The argument, if successful, must demonstrate the existence of God. Although I will say that on this there can be varying degrees of success between the different arguments. More on that below.

Because there are two ways that anything can be demonstrated:

  1. Propter quid, which moves from the cause to its effects.
  2. Quia, in which an effect reveals something about it’s cause.

Before I give you an example of each, I need to highlight a common but grave mistake that people make regarding the meaning of “cause” when addressing Thomistic philosophy.

Often, when we hear the word “cause” we only think of what St. Thomas would call an “efficient cause” which is the kind of cause that produces something. A carpenter, for example, builds a chair. Under a Thomistic analysis, there are more causal considerations going on here than simply efficient causality. For Aquinas, a cause is anything that contributes to at thing’s being and there are four ways this can be done.

  1. Material cause: That out of which a thing is made or becomes. i.e., wood.
  2. Formal cause: The internal principle of organization that gives unity to the whole and gives its definition. i.e. “Adirondack chair”.
  3. Efficient cause: That which produces a thing by making it actual. I.e, A carpenter.
  4. Final cause: That for which the thing tends towards. I.e., “Being an Adirondack Chair”

When St. Thomas uses the word “cause” in a demonstration, he demonstrates by means the formal cause but what he intends to demonstrate is an efficient cause. Let me put this another way. The way this looks in a proper quid demonstration is that we take what we already know about some real thing and explain it’s effects by reference to the formal powers of it’s essence. For quia arguments, we look at the real effects as evidence for a cause and use the form of the effects to reveal to us something about the essence of their cause as the kind of thing that can produce the observed effects. The reason for this is that when you apply logic to questions about real things, you look to how things operate in the real world. So, while both kinds of demonstration point to an efficient cause, we arrive at the conclusion by reference to the form of the cause or effect as a middle term. Because that’s how demonstration works: by examining the relationship between concepts. In logic, this is only about concepts abstracted from real things but in a philosophical demonstration, we need to turn to things in the real world and their principles.

One other thing to know about the form of a thing is that it makes whatever it informs be a member of its kind and is the source of the activities proper to it. That sounds complicated but it’s actually as easy as saying that the form of a tree is the aspect of the tree that organizes the matter in such a way that the “wood” a tree rather than a boat and what determines the ways in which the tree can act.*

We can apply this understanding to a propter quid demonstration about a tree, we have enough of a grasp of the tree’s nature that we can say with confidence that trees photosynthesize. Hence we could make an argument like this:

All trees are that which photosynthesize

Billy is a tree (who names trees?)

Therefore, Billy is something that photosynthesizes.

Here “photosynthesize” connects to Billy through the form of the tree and its powers. From premise to conclusion, the form of “Tree” does the legwork to help us understand something about the nature of Billy. Our conclusion that Billy photosynthesizes is rooted in the formal cause of trees (abstractly) and Billy (concretely).

What about a demonstration by quia?

Well, every propter quid argument begins with a question like “is the wobble in the orbits Neptune and Uranus caused by a ninth planet?” Prior to March 13, 1930 this was the state of the question and we were hitherto unaware of the existence of Pluto or anything about the now dethroned ninth planet. Thanks to the measurements and calculation of W.H. Pinkering, humanity produced an empirical demonstration of Pluto’s existence and location which led to its subsequent observation by telescope.

By observing Pluto’s effects, we were able to know that Pluto existed as well as a number of other aspects proper to Pluto, even before direct observation. Another important point of historical interest is that prior to Pinkering’s measurements and calculations, Pircival Lowell posited the existence of a 9th planet based on the same effects observed by Pinkering. Lowell’s calculations did not go quite as far as Pinkering’s in that he was unable to provide the right kind of information about this ninth planet that allowed for its observation.

This is just one example of a quia demonstration and while the details may be rushed or a bit murky, it wouldn’t be hard to produce another example. Regardless, I think that the discovery of Pluto gives us a few key insights into the nature of quia argumentation:

  1. The argument begins in an effect observed by our senses.
  2. A quia argument uses a nominal definition related to the effect.
  3. The effect serves as the “connecting” factor or “middle term” in its argumentation.
  4. In employing a quia argument, the person doing the demonstration must use reasoning proper to its science. So, if it’s astronomy then we should use mathematical physics and observations rather than a chemical analysis of how to better make cookies.
  5. We also know that even when quia arguments succeed, not all immediately demonstrate as much about the cause as others might.

All of this, as I’ll show you in later posts, come into play when we’re talking about the existence of God.

For now, however, to which kind of demonstration do arguments about God’s existence belong?

The answer should be relatively clear from last week’s post:

Human knowledge always begins in the senses and it is through reflection on our sense perceptions that we can obtain knowledge of a real thing’s form but since we cannot begin our argument with a knowledge of God’s real essence because we don’t experience Him through our senses, then we cannot have a propter quid demonstration for His existence. We may come to know something about His essence as necessarily existing through later quia demonstration but that renders any propter quid demonstration superfluous. So, again, we cannot argue to the actual existence of God through the examination of a proposed definition for God. (If you need a reminder on why this is the case, then read the “Ontological Argument” section on this post.)

Similarly, all argument’s for God must begin with what we observe in the senses, follow reasoning proper to the science we’re pursuing, and must also provide us with a way to know something about God beyond His existence as a cause.

Can we do that?


And I’ll show you how…


I need to string you a long a bit 🙂

Or I need to get my kid to bed and therefore need to end this post.

Next week, I’ll offer two popular arguments that I think almost satisfy the criteria for a successful argument for God’s existence. I am, of course, talking about William Lane Craig and the moral argument and the Kalam Cosmological Argument. I do have one caveat:

While these arguments work, they do not work under Craig’s metaphysical backdrop. However, when understood in light of a Thomistic metaphysical schema, they validly conclude to the existence of God. Interestingly enough, as you’ll see, I think that the moral argument is actually stronger than the Kalam argument.

Should be fun.

Please like and share! Be a kind aid to a poor academic outside of academia, this is my only outlet for sanity now!

God bless,

Jonathan L. Stute, M.A.

P.S. While you’re waiting, check out this awesome course by my friend, Dr. Scott M. Sullivan on How to Prove God Exists: The Cosmological Argument, which covers the first cause argument by St. Thomas Aquinas, which is one of my favorites. Guess what else? It’s never been refuted! Want to see why? Check out the course by clicking the link below:

How to Prove God Exists: The Cosmological Argument