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St Thomas and First Cause

Yesterday (January 28th) was the feast day in the Church of Saint Thomas Aquinas, the great philosopher, and a Doctor of the Church. He wrote much about the Nature of God, including his massive Summa Theologica. To that end, this reminded me of a part of a book by another Thomas (Thomas E Woods), called "How The Catholic Church Built Western Civilisation", where he takes the idea of Aquinas' First Cause and simplifies it for the reader. I will link to the page on Google books HERE, but also excerpt it below -

Saint Thomas's views are best understood if we begin with thought experiments from the secular world. Suppose you want to purchase a pound of turkey at the deli counter. Upon arrival there, you find that you must take a number before you can place your order. Just as you are about to take a number, however, you find that you are required to take a number before you can take a number. And just as you are about to take that number, you find that you must first take yet another number.Thus you must take a number to take a number to take a number to be able to place your order at the deli counter.

Suppose further that the series of numbers you are required to take is infinite. Every single time you are about to take a number, you discover that there exists a prior number you must first take before you can take the next number. You will never get to the deli counter under such conditions. From now until the end of time you will be forever taking numbers . Now if you were to come across someone in the grocery store walking around with half a pound of roast beef that he had purchased at the deli counter, you would instantly know that the series of numbers must in fact not go on forever.



We have seen that with an infinite series of numbers no one could ever reach the deli counter. But the person with the roast beef must somehow have managed to get to the counter. Thus the series cannot be infinite.Consider another example. Suppose you wish to register for a college course, and you therefore pay a visit to the registrar, Mr. Smith. Mr. Smith tells you that in order to register for that particular course, you must see Mr. Jones. Mr. Jones, in turn, instructs you to see Mr. Young. Mr. Young sends you to Mr. Brown. If this series went on infinitely-if there were always another person you had to see before you could register-it is abundantly clear that you would never be able to register for the course.

These examples may appear quite remote from the question of God's existence, but they are not; Saint Thomas's proof is in a certain way analogous to them both. He begins with the idea that every effect requires a cause, and that nothing that exists in the physical world is the cause of its own existence. This is known as the principle of sufficient reason. When we encounter a table, for example, we know perfectly well that it did not come into existence spontaneously. It owes its existence to something else: a builder and previously existing raw materials. An existing thing Z owes its existence to some cause Y. But Y itself, not being self-existing, is also in need of a cause. Y owes its own existence to cause X. But now X must be accounted for. X owes its existence to cause W.

We are faced, as with the examples of the deli counter and the college course, with the difficulties posed by an infinite series. In this case, we are faced with the following problem: Every cause of a given effect itself demands a cause in order to account for its own existence; this cause in turn requires a cause, and so on. If we have an infinite series on our hands, in which each cause itself requires a cause, then nothing could ever have come into existence.

Saint Thomas explains that there must, therefore, be an Uncaused Cause-a cause that is not itself in need of a cause. This first cause can therefore begin the sequence of causes. This first cause, Saint Thomas says, is God. God is the one self-existing being whose existence is part of His very essence. No human being must exist; there was a time before each one came into existence, and the world will continue to exist after each one perishes. Existence is not part of the essence of any human being. But God is different. He cannot not exist. And He depends on nothing prior to Himself in order to account for His existence.
I think I had heard this type of thing before, but seeing it put in this way struck me the first time I read it, so much so that I actually burst out laughing for several minutes at how brilliant and logical and, well, true it was.