L2 Reading Guide: Omnipotence

Reading: Aquinas, “God Is Omnipotent” (pp. 138-140) & Mavrodes, “Some Puzzles Concerning Omnipotence” (pp. 141-143)

Aquinas

In this reading, Aquinas discusses how we should interpret or understand the claim that God is omnipotent. Does the claim that God is all-powerful entail that He is able to do anything and everything or are there some things even an omnipotent being cannot do?

For those of you who are not used to reading Aquinas, it may be helpful to outline the structure of this short excerpt from the Summa. Aquinas begins, as is his standard practice, by identifying objections. He indicates disagreement with the objections, then at “I answer that” begins to sketch his own position. After he finishes describing his position, he then responds directly to each objection.

“The Philosopher” = Aristotle

Aquinas begins to articulate his own position at the bottom of p. 138. At the top of p. 139, he tells us that “this phrase, God can do all things, is rightly understood to mean that God can do all things that are possible”. But this claim needs further clarification, for there are different senses in which something is possible or impossible. For instance, it is physically impossible for me to pick up my car using my own brute strength; however, it is physically possible for a lot of people working together to pick up my car. However, if God can do all things just means that he can do all things that are physically possible for human beings to do, then that’s not that impressive.

Aquinas explores two interpretations of the claim that something is possible. We might mean that it is possible “in relation to some power”, either human or divine OR we might mean that it is possible “absolutely”. Aquinas rejects the first alternative. I’ve already partially explained above why we wouldn’t want to define God’s omnipotence “in relation to” human power. See the text for Aquinas’ explanation of why it is a mistake to define God’s omnipotence as the ability to “do all things that are possible to His power”. Having rejected the first alternative, Aquinas then explains what is meant by the claim that an omnipotent being can do anything that is “possible absolutely”. His initial explication may be a bit puzzling to some of you, but it becomes clearer as he goes on. Although he does not use this terminology, Aquinas is essentially saying that God can do anything that is logically possible. He then concludes that omnipotence doesn’t imply the ability to do things that are logically impossible; still, “it is more appropriate to say that such things cannot be done, than that God cannot do them” (139).

At this point, Aquinas turns his attention to responding to the 4 objections he sketched on p. 138. The most interesting and informative of these is his response to Objection 2.

Mavrodes

Mavrodes begins by summarizing Aquinas’ position. He then contrasts two counter-examples to the doctrine of omnipotence:

(1) God “cannot draw a square circle”.
(2) God “cannot create a stone too heavy for Him to lift”.


He points out that Aquinas has a perfectly good explanation for why (1) is not a threat to God’s omnipotence. Ultimately, he thinks that Aquinas’ explanation also extends to (2). However, he thinks that (2) is “a more involved problem”. Here, he contrasts the claim that “x is able to draw a square circle” with the claim that “x is able to make a thing too heavy for x to lift”; the former claim, but not the latter, obviously “involve(s) a contradiction”. So, there appears to be a significant difference between these two claims. Mavrodes then argues that counterexample (2) does not force us to give up the doctrine of God’s omnipotence because omnipotence is not damaged by the inability to do “self-contradictory thing(s)” (142). Mavrodes must, then, establish that (2) involves a contradiction. Mavrodes’ main argument begins with “The specious nature of the problem may be seen in this way” (left-hand column, p. 142). Mavrodes notes that the objector can't, in articulating his objection, assume that God is NOT omnipotent, for then his argument would be circular. So, the objector must be understood as mounting a reductio argument. For those of you who don’t know or need a refresher, a reductio (aka reductio ad absurdum) seeks to demonstrate the falsity of a particular claim (“God is omnipotent”, “God exists”, “Human beings are naturally good”, etc. ) by assuming its truth and showing that the assumption that the claim is true produces an absurdity or a contradiction. Mavrodes claims that the objector can’t construct a successful reductio: “On the assumption that God is omnipotent, the phrase ‘a stone too heavy for God to lift’ becomes self-contradictory.” (142) Mavrodes unpacks this line of thought, then considers the possibility that someone might insist that the phrase “a stone too heavy for God (an omnipotent being) to lift” is NOT a contradiction in terms. Mavrodes argues that even if we assume the objector is right, this does not undermine the doctrine of God’s omnipotence. The last few paragraphs propose a different way of understanding why (2) is a specious challenge to God’s omnipotence.