Was Aquinas’ proof of God sufficient? What was written by Aquinas on faith and reason is well-known. Aquinas sought to reconcile faith and reason. I recently re-read his treatise again, with an eye to discover what arguments he used to prove the existence of God? I subsequently asked myself if his arguments and five proofs of God are convincing or not. Thomas Aquinas, in his famed work, “Summa Theologica”, set out to prove the existence of God. His entire argument was framed with three inquiries, namely:
(1) Whether the proposition “God exists” is self-evident?
(2) Whether it is demonstrable?
(3) Whether God exists?
After careful research I discovered that in the comprehensive argument, Aquinas turned to the prime sources of his day; quoting the Bible, the Last of the Greek Fathers, Saint John Damascene; the Philosopher, known to be Aristotle; The Roman statesman and philosopher, Anicius Manlius Severinus Boethius; to Augustine, and also referenced Aristotle’s “Metaphysics”. He leaned on the work of these men to prove the existence of God.
Herein, we will briefly discuss the validity of the final, most pertinent inquiry, as it pertains to the question of God’s existence. In Article 3, Aquinas answers the question, “Whether God exists?” Accordingly, Aquinas claims, “The existence of God can be proved in five ways.” These are known as Aquinas’ proof of God or his five proofs of God.
As pages four and five of “Summa Theologica” disclose:
“The first… is the argument for motion.”
“The second… the nature of efficient cause.”
“The third… possibility and necessity.”
“The fourth… the gradation to be found in things.”
“The fifth… the governance of the world.”
Upon close examination, I find Aquinas’ proof of God to be better rhetorical instruments than actual proofs for the existence of God. They appear to be different facets of defense, but are all predicated on a single argument. Plainly put, ‘If we trace all things back to their source, we’ll arrive at God.’ Be it “a first mover,” “a first efficient cause,” “the existence of some being having of itself its own necessity,” “something which is to all things the cause of their being,” or some intelligent being “by whom all natural things are directed to their end.” This is the pattern of thought for each argument presented in his five proofs of God.
Interestingly, another common thread proving the oneness of this argument is seen dangling in the first three proofs. The phrases “this cannot go on to infinity,” “it is not possible to go on to infinity,” and lastly, “it is impossible to go on to infinity” are used in the respective five proofs of God. Logically, this argument sounds correct, but it still remains a singular argument, not a proof of the existence of God.
That Aquinas was grasping for straws is evident in his use of another clever rhetorical device, a blatant application of epistrophe. Notice how he ends each of the paragraphs outlining his proofs with the same phrasings:
1. “and this everyone understands to be God.”
2. “to which everyone gives the name of God.”
3. “This all men speak of as God.”
4. “and this we call God.”
5. “and this being we call God.”
Was this what everyone and all men speak of and know as God? Surely, the very argument itself proves the opposite. The phrase is meant to present a unified front on the issue. It’s like the modern ‘Global Warming’ debate in which proponents of the theory of man-caused warming argue, ‘The science is conclusive,’ or ‘scientists agree’, attempting to convey a broad, finalized consensus. Surely, the clerics, bishops, and proponents of the Christian faith agreed that everyone and all men naturally arrive at God as the source of all; however, this did not conclusively prove their claims.
Although I believe Aquinas was sincere in his beliefs and defense of the faith, I find his arguments for the existence of God wanting. Aquinas’ proof of God endeavor to prove the existence of God; however, proof is much more tangible than mere arguments and reasoning. Logically speaking, yes, there must be a source of all things. Outside the realm of logic, though, proving the existence of such a source proves to be more challenging.
True to the dominant cultural norms of his time, Aquinas’ proof of God subordinates all logic to the authority of the Bible. His paradigm was rooted in the book. His five proofs of God disallowed any further inspection, and were presented as proofs, when in fact they were mere arguments. Arguments, I might add, as valid, or invalid as those which sought to prove that God does not exist.