An excerpt From Aquinas On Being and Essence

On Being and Essence

Everything that pertains to a thing, however, either is caused by the principles of its own nature, as risibility in man, or else comes from some extrinsic principle, as light in the air from the influence of the sun. Now, it cannot be that existence itself is caused by the very form or quiddity of the thing (I mean as by an efficient cause), because then the thing would be its own efficient cause, and the thing would produce itself in existence, which is impossible. Therefore, everything the existence of which is other than its own nature has existence from another. And since everything that is through another is reduced to that which is through itself as to a first cause, there is something that is the cause of existing in all things in that this thing is existence only. Otherwise, we would have to go to infinity in causes, for everything that is not existence alone has a cause of its existence, as said above. It is clear, therefore, that the intelligences are form and existence and have existence from the first being, which is existence alone, and this is the first cause, which is God.

Funnily enough, I just recently started skimming On Being and Essence, which is only I think seventeen pages or so in its entirety. I also picked up a book that really unpacks it. I haven’t read that yet, but On Being and Essence is a pretty nuanced philosophical document on Being written early in St. Thomas’ career. And, whereas the arguments in the Five Ways don’t present all the background material they rely on, I’ve heard On Being does present it. I’m sure it can’t trace everything back to the beginning of philosophy, but that in itself makes it interesting and perhaps more approachable.

Anyway, those are my comments, but this is something I wanted to read.

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Here is the whole document if anyone’s interested.

Yeah, i think this is a very important document if one is giving Aquinas’ arguments the seriousness they deserve.

Thanks for posting.

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