The Doctrine of Divine Simplicity is a concept within at least the Abrahamic religions regarding the nature of God (the term “Doctrine of Divine Simplicity” is a particular reference to the official stance of the Catholic Church on this issue).
It states that God is not complex or composed of multiple parts that, together, define the being we call ‘God’. According to this doctrine, God is infinitely, maximally simple and indivisible as well as unchangeable (as being unchangeable would seem to logically follow from uttermost simplicity nad indivisibility).
In this article I will begin with several questions I have regarding the concept of God being infinitely simple and indivisible which hardly make it appear to be a coherent claim even within Abrahamic religion. Then my last few points will be direct refutations of the Doctrine as I currently understand it, having read Question 3, Article 7 of Aquinas’ Summa Theologica and several explanations from believers.
1. Question: Indivisible and Immaterial?
If God is “immaterial”, then what does it even mean to be “divisible” or “indivisible”? Those terms refer to material objects being broken down into their components, or being unable to be broken down that way, respectively. It would be incoherent and inapplicable to use it in reference to something “immaterial” because there would be no parts – not even one – for the thing to be broken down to.
2. Question: Why does the Argument from Gradation of Being not apply to complexity and divisibility?
In his works, the Catholic theologian Thomas Aquinas, who was a major proponent of Divine Simplicity, explained several ‘proofs’ for the existence of God. One of these proofs was the Argument from Gradation of Being which seems, if one accepts its reasoning, that it would mean that God is infinitely complex. The Argument from Gradation of Being can be simplified to this form:
2. Predications of degree require reference to the “uttermost” case (e.g., a thing is said to be hotter according as it more nearly resembles that which is hottest).
3. The maximum in any genus is the cause of all in that genus.
4. Therefore there must also be something which is to all beings the cause of their being, goodness, and every other perfection; and this we call God.
But it seems that this argument would also apply to the qualities of complexity and divisibility. For example, this argument could be made which draws upon its logic:
1. There is complexity and divisibility of objects and beings in nature.
2. According to the Argument from Gradation of Being, the thing which is the maximum or uttermost example of complexity and divisibility is the cause of all things complex and divisible. (The cause of all complexity is a thing that is infinitely complex and infinitely divisible)
3. We call ‘God’ that which is to all beings the cause of their being, goodness, and every other perfection.
4. Therefore God must be infinitely complex and infinitely divisible.
3. Question: Why would the infinitely simple appear infinitely complex?
Thomas Aquinas argued that humans have “finite” minds and thus cannot understand anything that is “infinite” in some way. Therefore he claims that since God is infinitely simple, the human mind will always perceive God as being infinitely complex. But there are issues with this argument that must be addressed:
3A. The arguments that God would be complex are based on logic. It is not mere feeling or intuition that proponents of Divine Simplicity must refute. They must address the logical arguments for why God would need to be extremely complex. Logic indicates that God would need to be extremely complex due to his capacity for an infinite range of thought, action, knowledge and so forth, and also due to the Catholics’ own Argument from Gradation of Being if one accepts that argument’s reasoning in other contexts where its logic applies.
But what if a person attempts to evade these points by claiming that since humans have limited, finite minds, we therefore cannot use logical arguments to make conclusions about God? If we accepted their claim, then all arguments for any conclusion about God would be invalid and unreliable, including those in favor of God being simple, because all these arguments attempt to use logic to reach their conclusion. Any particular belief about God’s nature – let alone his existence – would be totally arbitrary.
Logic and evidence is what demonstrably indicates what is most likely true or false, so to reject logic and evidence as a means for understanding the God concept would only make all conclusions about God equally arbitrary. Rejecting logic would not favor the Theist’s beliefs.
3B. Non sequitur. The argument that a finite mind would perceive something infinitely simple as infinitely complex is a non sequitur. There is no logical reason why a mind that cannot understand infinities or the extreme degree of something would view those infinities and extremes as the exact opposite of what it really is. Why would they not just view it as just complex enough for them to understand it, for example?
Consider this question: By the argument’s logic, would a finite mind perceive actual infinite complexity as infinitely simple, or correctly perceive it as infinitely complex?
Any answer reveals a problem for the Theist. If a finite mind perceives infinities as the opposite of what they are, then such as in this example, something can indeed appear infinitely simple to a finite mind. If that is the case, then why would a finite mind perceive infinites as the opposite of their true nature in the first place? Alternatively, if infinite complexity correctly as infinite complexity to a finite mind, then we must ask why infinite simplicity would not.
It seems as though theologians merely declared that finite minds cannot perceive simplicity arbitrarily for purposes of theological defense, rather than for logical reasons.
3C. Humans understand simplicity. Being simple sounds like a concept that a “finite” mind would be able to understand. Humans regularly perceive simplicity and gradations of complexity. So why would a maximally simple thing appear the complete opposite, as infinitely complex? Aquinas seems to lack sufficient support in this area.
Understanding simplicity does not seem to be a weak point for the human species. For example, the mathematical Law of Identity that states any given thing is the same as itself (A = A) is extremely simple and it is likewise extremely easy for humans to understand. The simpler and idea or concept is, the easier it is for humans to conceptualize and at least feel that they understand. So if God were just as simple or even more simple than a concept like that, then I see no reason that we would not be able to understand it.
But the human brain often simplifies ideas that are complex. So an infinitely complex being (or concept of it) would likely be conceptualized as simpler than it really is by a finite mind like Aquinas. That seems to be the more likely scenario of the two, given the points raised already in this section.
4. Refutation: Same Argument Problem
Even if Aquinas’s concept of Divine Simplicity were logically sound, then we could simply make the same claim about a non-god origin or foundation of the universe. In that case, Occam’s Razor would cut out the unnecessary assumption of a god because we already know the natural world exists. So the notion of God being simple and indivisible would not help support Theism even if it made sense.
5. Refutation: Static and Without Function
This is the main point against the notion of God being infinitely simple, indivisible, and unchangeable. A thing which is indivisible and unchangeable – and either once existed alone or is defined as “everything that exists” – would be static and without function.
Something with any sort of ability to act, such as to think or use speech, could not be indivisibly simple. Such a notion is illogical because the ability to do anything we have ever known necessitates multiple parts that interrelate and is in fact defined by the way those parts interact (even space itself is a part).
Consider any action you perform such as thinking or moving your arm. Without multiple parts, a thing can only exist in one state.
We have no evidence that something which consists of one part can behave in such a way. For the notion of divine simplicity to be valid, one must offer evidence for it even being a coherent concept. Then one must provide evidence on top of that for why that god probably exists.