First Cause Argument

       Thomas Aquinas argued that there are no a priori proofs of the existence of God. An a priori statement is sometimes described as a statement whose truth or falsity may be known before any appeal to experience. Experience is not irrelevant to discovering or learning what a given statement means, of course. Sometimes a key term must be defined, and such definition may depend on experience. Once the meaning of that term is understood, though, no evidence drawn from experience or observation can justify the claim of its truth or falsity. An example of an a priori statement might be Rene Descartes' famous line, "I think, therefore I am." It would seem obvious that our own existence is something we know "a priori".
       On the other hand, Thomas Aquinas firmly believed that there were several sound a posteriori proofs of God. An a posteriori statement is sometimes described as a statement that can be known to be true or false only on the basis of evidence obtained from experience and observation -- that is, it is empirical. Examples of "a posteriori" statements are "I have a freckle on my knee", "Saturn has rings", and "Brussels sprouts taste bad." Such statements can be checked and verified.
       Aquinas produced five "proofs" of God's existence, though only three seem useful to me, and even those three are far less than the "proofs" he imagined. To put it bluntly, he was completely wrong in stating that there were sound a posteriori PROOFS of divinity.
       One of Aquinas' arguments for the existence of God is called the first-cause argument. It proceeds something like this: every effect has a cause. The universe is an effect. Therefore the universe has a cause. That cause is God.
       The problem with this argument is shown by asking the simple question: what is the cause of God? The answer is that God is uncaused: he has always existed. Right away, the atheist can raise an objection: "Why must we assume that the universe has a cause? Perhaps the universe also always existed."
       Today, as a result of modern cosmology, a problem exists with this classic objection. All the scientific evidence points to the universe having a beginning: i.e. the Big Bang. This has been deeply disturbing to scientists, because the question of causation now becomes very significant. No explanation for the Big Bang has been found.
       There is a danger in this for Christians, though. It would not be wise to hop in at this juncture and shout "Ah ha!, God caused the Big Bang". We must not fall into the trap of a "God-of-the-gaps-theology. It must be noted that quantum physics postulates the possibility that, at least on the subatomic level, effects occur without causation: they are entirely random. Therefore the possibility exists that the universe is a similar quantum event -- a random flux in nothingness that resulted in the Universe as we know it. Arguably this appears weak and contrary to common sense, but much of the universe's operation is contrary to common sense, though demonstrably true (such as time dilation).
       Still, in the final analysis, it must be admitted that God as the cause for the Big Bang is a viable hypothesis, which meets the requirements of Occam's Razor, perhaps better than an entirely non-theistic explanation. Occam's Razor could perhaps be summarized by the acronym K.I.S.S. -- "keep it simple, stupid". That is, the simplest explanation for something that covers all the bases is probably the right one.