8. Summa Contra Gentiles By Thomas Aquinas Summary Book 1 Chapter 14-16

The previous post is here.

Chapter 14

that to acquire knowledge of God one must use the way of remotion

Having proved there is a God what is he?

The divine essence in it’s enormity cannot be understood entirely and must be investigated by remotion, which is a process of removing.  By learning what God is not we will develop a more perfect knowledge.  Since everything is distinct, if we can know what is distinct about God we can perhaps create a definition, and a genus so that we may know in general what God is.

Instead of asking, “what?” We will ask what God is not.  Through this process we’ll know more, but will not have perfect knowledge of God.  (Remember there are two ways of knowing, by revelation and by reason, both are necessary.)

Let us star with something already proven, that God is eternal.  This is also confirmed by scripture.

Chapter 15

That God is eternal.

Things that begin or cease suffer to change. We’ve already shown that God is unchangeable and has no beginning or end.

Only things that move are measured by time as it is just a measurement of movement.  God being unmoved, he does not participate in time, there is no non-being before after his existence, he has his entire existence simultaneously, which is eternity.  (Eternity in this way is not an infinity. Spend a little time thinking on this one.)

There are many things that can be and not be.  All of these have a cause.  But as we proved with Aristotle’s argument, we can’t have infinity causes.  There MUST be a causal something in order to bring these things generative and corruptive things about.  These necessary causes can either be caused or has no such cause and is necessary of itself.  This is the first necessary thing, this is the unmoved mover, this is God.

Therefore, God is eternal, since whatever is necessary of itself is eternal.

In Physics, Aristotle proves the everlastingness of movement from the everlastingness of time.  This leads us to know the everlastingness of mover.  Even if we ignore or discard our findings about time, we still have to deal with the everlastingness of substance.  (Check out Aristotle on this.  His hylomorphism holds that substance is matter+form.  Aquinas agrees.   Note well.  This is not heuristic.  This is not “a way to think about things.”  Things are substantially what they are due to their material and form.   Flour and other ingredients are just ingredients.  Mix them up with a plan in mind, bake them and give them a form and you get bread.)

Chapter 16

That in God there is no passive potency

If God is eternal he cannot be in potency.

Nearly everything that exists has some potency, and as such could as readily be as not be.  God, as we have shown, cannot not be, therefore he has no potency to be.  (More from Aristotle’s Metaphysics.  Things are not always fully actualized.  For example, you have the potency for perfection, but won’t necessarily achieve this.  God has no potency.  He is fully act.  He is fully actual.)

What must exist can in no way have a potential existence.  God must exist so he cannot have possible or potential existence.  Again, God must be entirely actual.

That which is partially actual acts not by its whole self but because of a part of itself.  If it doesn’t act as its whole self, it is not the first agent.  Again, God must be entirely actual.

Also, anything that is in potency is passive in that respect and when the potency is realized there must be motion.  God being immovable he cannot have potency as actualizing that potency requires motion.

Lastly, anything that moves from potency to act must have been acted upon.  This actor must have been acted on as well, and so on.  This series must end by something that is entirely actual, this is God.






My commentary is in parenthesis.

I am reading the Fr. Laurence Shapcote, OP translation.  I have the opera Latin/English 2 volume set from the Aquinas Institute.  You can buy it here.   I think you can find it in less expensive out of copyright editions if you look for the Dominican Friars Translation on Bezos’ site, or for free at archive.org.

I’m reading about 35 chapters per month. It’ll take about two years.  A few pages a day will get it done.   Join me.

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