Many atheists mistake materialism for science. It is true that you cannot prove the existence of God by deduction. You cannot put God in a test tube or under a microscope and subject Him to various experiments. You cannot prove the existence of an immaterial being by material means.
|Induction by Aquinas|
You can, however, prove that God — or a god — exists by induction. This is the basis of Aquinas’s five proofs of God’s existence. A creation necessarily implies a Creator. An effect necessarily implies a cause, and, ultimately, an uncaused Cause to start things off. And so on.
The fact is that many atheists do, in fact, recognize a supreme being: themselves. This may be humble or arrogant, but it is always egocentric. They recognize only themselves as the be-all and end-all of existence; they are the cause, nature, and purpose of the universe. (A common mistake many atheists and even theists make is to assume that “religion” necessarily concerns a belief in an afterlife. Not all religions have that doctrine. Even Judaism, the parent religion of both Christianity and Islam, developed the concept relatively late. The Sadducees, who were always trying to trip up Jesus with questions intended to show that belief in an afterlife is nonsense, are a case in point.)
|When the Dumb Ox bellows, people listen.|
This is what G. K. Chesterton characterized in Orthodoxy (1908) as a belief in the god within, the Inner Light. Unfortunately, this sort of egoism is rampant today not only among “atheists,” but among religious believers who insist on trying to force faith to do the job of reason. This is a tendency that manifests in many ways, such as trying to make charity do the work of justice, “gift” do the work of “exchange,” or of nonsense do the work of common sense.
This is why, in my opinion, Chesterton repeated his admonitions regarding the dangers of using faith in place of reason in the introduction he wrote to Fulton Sheen’s God and Intelligence in Modern Philosophy (1925), and then again in his own sketch of Aquinas, Saint Thomas Aquinas: The “Dumb Ox” (1933). As Chesterton cautioned, in what comes across to me as a very pointed, even barbed warning to his own followers, we must argue “not on documents of faith, but on the reasons and statements of the philosophers themselves,” a quote he took from the conclusion of Aquinas’s On the Unity of the Intellect Against the Averroists.