In St. Thomas Aquinas’ opinion, God exists. In fact, Mr. Aquinas wrote up five ways to prove the existence of this being known as God in his writing “The Five Ways.” For example, in Aquinas’ second way, he concludes that because there are causes in this universe, there must be a first cause. This first cause, he says, is God. Aquinas takes a few steps (or premises) to reach this “first cause” conclusion.

In the world of sensible things, we find there is an order of efficient causes.

Here, Aquinas points out that there are, indeed, things in this universe that are caused. He simply states that there are such things as causes in existence.

There is no case known (neither is it, indeed, possible) in which a thing is found to be the efficient cause of itself; for so it would be prior to itself, which is impossible.

Aquinas recognizes that, if there are indeed causes in our universe, then either the cause caused itself, or it was caused by something else. With the above statement, Aquinas rules out the possibility of anything causing itself. In order for something to cause itself, that something would have had to exist before its own existence, in order to cause itself, which is a total paradox. It is impossible to exist before you exist, in order to create yourself. That leaves only one option. That if something is caused, then something else caused it.

After pointing out the fact that there are things that are caused by other things, Aquinas claims that this causal series must be a result of either an infinite series of causes or a first cause. He quickly argues that an infinite series of causes is impossible.

Now in efficient causes it is not possible to go on to infinity, because in all efficient causes following in order, the first is the cause of the intermediate cause, and the intermediate is the cause of the ultimate cause, whether the intermediate cause be several, or one only. Now to take away the cause is to take away the effect. Therefore, if there be no first cause among efficient causes, there will be no ultimate, nor any intermediate, cause. But if in efficient causes it is possible to go on to infinity, there will be no first efficient cause, neither will there be an ultimate effect, nor any intermediate efficient causes; all of which is plainly false.

Aquinas basically says there must have ultimately been a first cause, because if there was never a first cause, there would be no causes now. If the series went back to infinity, there would be no first cause, and without a first cause, nothing could have been caused. But it has already been confirmed that there are causes.

Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God.

Aquinas’ argument is sound and valid all the way through. However, his last statement, “everyone gives the name of God,” does not seem to be very well grounded. Just because there seems to have been a first cause, why does it have to be God? And to say that everyone gives anything any name is to generalize carelessly.

First of all, everyone does not believe in one certain god. Different religions hold different views of who and what God is. How does this argument prove the first cause to be Aquinas’ Roman Catholic God? Secondly, what if the first cause was not God? Could it not be the Big Bang, or (as Hume’s Philo put it) just a giant plant seed? And finally, how did this first cause come to be? Isn’t claiming the first cause to be eternal just as absurd as the idea of an infinite series of causes?

Well, to take up the latter question, claiming an infinite series of causes is not as absurd as claiming the first cause to be eternal. The infinite series of causes defies logic, as already proved by Aquinas. The idea of an eternal first cause defies no such law of logic. An eternal object is certainly foreign to humans, but that does not say that no such object exists. There is no natural or logical law that would prevent such a being to exist. To say that an eternal being exists is not a paradox within itself.

The idea, also, does not suggest that the first cause caused itself. Such an idea was already proved wrong by Aquinas. The idea suggests an eternal being, caused by nothing – a being that always was, and being the first efficient cause, started the causal series.

As far as why must this first cause be God, instead of some other religion’s god, a big bang or a giant seed, Aquinas does not go into. In fact, his argument could be said to prove the existence of a first cause, but failing to prove it to be the traditional Christian God. It is quite possible that it was not Aquinas’ intention to argue that in any of these five ways. It certainly could be considered a completely different subject to be debated elsewhere or in another writing. But to begin where Aquinas left off, there is a possible argument that would suggest that Aquinas’ first cause argument does prove the existence of the Christian God.

For if there was a first cause that all other causes followed from, wouldn’t the existence of all following causes be dependant always on the first cause? If there were no first cause, then all following causes would not exist. No matter how far after the first cause a cause takes place, that new cause will always be dependant on the existence of the first cause. So, in that sense, the first cause sustains all following causes and is eternal.

If the traditional Christian God did exist and was the first cause, then when He created the universe, he created out of Himself, because that was all that was in existence to create with. If that were true, then all of creation could not exist without God. His existence would be sustaining all of creation. If He were ever to cease existing, all of creation would cease to exist as well. So, if it were true that the first cause must necessarily be in order for all other causes to be, it can be said to have traits similar to that of the Christian God.

All power that exists must have been created by God, out of Himself, which was all there was to create out of in the beginning. Therefore, God sustains the existence of all power, and therefore is all-powerful.

Because God sustains all created things, there is an intimate bond between Himself and His creation. This bond must be strong, because the created thing comes from within God, for God was all there was, in the beginning, to create all things. This intimacy and closeness the Creator has with His creation would be love. For would the Creator hate Himself? This could give this first cause and sustainer the attribute of all-loving.

Again, if God created or is the first cause of everything, then He created or caused all there is to know. In that way, He is certainly all-knowing.

So, if God is the first cause that Aquinas was talking about, He is eternal, in that His existence is necessary for all other existences and will forever more be. He is the creator and designer of the universe, in that He caused or created it all. He is omnipotent, in that all power must have been created or caused by Him. He is omniscient, in that all there is to know was created or caused by Him. And he is all-loving, in that all creation was made through and in Him, and He would not be unloving to parts of Himself with which He holds an intimate existence with.

St. Thomas Aquinas proves there must have been a first cause. He called this first cause God, but being the first cause, God is not only the watchmaker (first cause), He is the watch’s battery (sustainer).