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Category: SAMT

A tour through Saint Thomas Aquinas’s Summa Contra Gentiles.

April 19, 2015 | 16 Comments

Summary Against Modern Thought: Proving God is Omniscient

This may be proved in three ways. The first...
This may be proved in three ways. The first…
See the first post in this series for an explanation and guide of our tour of Summa Contra Gentiles. All posts are under the category SAMT.

Previous post.

My predictions were right: attentions flagged. Yet we have to plow through this material. I recall in a course on “Long-memory time series” sitting through a proof that took four hours (spread over two weeks). The destination was unremarkable and the only way anybody knew to get there was through a dense forest. Here the going is slightly easier, plus our destination a lot more interesting.

Be sure to read at least the last Note.

Chapter 47 That God Understands Himself Perfectly (alternate translation)

[3]…A material thing is made intelligible by being abstracted from matter and from material conditions. Wherefore that which by its nature is severed from matter and from material conditions, is by its very nature intelligible. Now every intelligible is understood according as it is actually one with the intelligent: and God is Himself intelligent, as we have proved.[1] Therefore since He is altogether immaterial, and is absolutely one with Himself, He understands Himself most perfectly.

Notes We’re skipping around, but this material is stunningly important for understanding the immateriality of the intellect. Not just of God’s. Ours, too. Our understanding of the essence of material things cannot itself be material. Ask Jack Aubrey would say, “Ain’t you amazed?”

Chapter 48 That God Knows Only Himself First And Per Se (alternate translation)

[3]…It is impossible to understand simultaneously several things first and per se: since one operation cannot terminate simultaneously in several things. Now God understands Himself sometimes, as we have proved.[2] Therefore if He understands something else by way of an object understood first and per se, it follows that His intellect is changed from consideration to consideration of that thing. But this thing is less excellent than He. Therefore the divine intellect would be changed for the worse: which is impossible.

Notes Given the premises, I can’t see even ardent atheists not accepting this. Don’t forget the “given the premises” part. Review, review, review.

Chapter 49 That God Knows Things Other Than Himself (alternate translation)

[2]…For the knowledge of an effect is sufficiently obtained from knowledge of the cause: wherefore we are said to know a thing when we know its cause.[1] Now God by His essence is the cause of being in other things. Since therefore He knows His own essence most fully, we must conclude that He knows other things also.

Notes [1] 1 Poster. Anal. ii. 1. (Aristotle, of course). This one is used in Science, too.

Chapter 50 That God Has Proper Knowledge Of All Things (alternate translation)

[2]…let us suppose that God is the cause of every being, which is clear to a certain extent from what has been said above,[2] and will be more fully proved further on.[3] Accordingly then there can be nothing in a thing without its being caused by Him indirectly or directly. Now if the cause be known its effect is known. Wherefore all that is in anything whatsoever can be known if God be known as well as all the causes intervening between God and that thing.

Now God knows Himself and all the causes that intervene between Him and any thing whatever. For it has been shown already that He knows Himself perfectly.[4] And through knowing Himself He knows whatever proceeds from Him immediately: and again through knowing this, He knows whatever proceeds therefrom immediately, and so on as regards every intervening cause until the ultimate effect. Therefore God knows whatever is in a thing. Now this is to have proper and complete knowledge of a thing, namely, to know whatever is in a thing, whether common or proper. Therefore God has proper knowledge of things, according as they are distinct from one another.

Notes We are accepting, at least for the sake of argument, that God is the ultimate cause of every being. The rest follows immediately. The first paragraph (as always, I added the break) is succinct. Even if you skip the remaining notes, do read the last.

[3] Further. Whatever acts by intellect, has knowledge of what it does, as regards the proper idea of the thing done: because the knowledge of the doer appoints the form to the thing done. Now God is cause of things by His intellect: since His being is His act of intelligence, and every thing acts in so far as it is actual. Therefore He knows His effect properly, according as it is distinct from others.

Notes Which reminds us of George Carlin’s defense in a case of bank robbery, “I’m sorry, judge, I just forgot.”

[4] Moreover. The distinction of things cannot arise from chance, for it has a fixed order. Hence it follows that the distinction among things proceeds from the intention of some cause. But it cannot proceed from the intention of a cause that acts from natural necessity: because nature is determined to one thing, so that nothing that acts from natural necessity can have an intention in relation to several things considered as distinct from one another.

It remains therefore that the distinction among things arises from the intention of a cause endowed with knowledge. Now it would seem proper to an intellect to consider the distinction among things: wherefore Anaxagoras[5] declared that an intellect was the principle of distinction. But taken as a whole the distinction of things cannot proceed from the intention of any second cause, since all such causes are included in the universality of distinct effects. Wherefore it belongs to the first cause, which is of itself distinct from all others, to intend the distinction among all things. Therefore God knows things as distinct….

Notes “The distinction of things cannot arise from chance,” which says it all. The cause must have knowledge, because causes are directed towards an end. As for the rest…

Recapitulation. We started with knowledge our sense impressions gave us: that some things change. Why? Because of some cause. What was the nature of the cause for the per-se here-and-now cause? A First Mover. We proved this First Mover had to be the same for every change. “It” had to have no potentiality, “it” was outside time, i.e. eternal, that this Mover was God. It followed that God’s existence and essence were one, that He had no body or materiality, that God could not be known completely, but was Good, i.e. the basis and definition of Good.

And now, though there are a details to mop up (mostly in characterizing this knowledge), we have finally proved that God knows everything. Omniscience. We assumed Omnipotence, but we have already partly proved that. An amazing string of deductions, no? Yes. We’re moving towards God is Truth, Happiness, and all that. After we mop up the characteristics of God, we prove God is the creator, creating big-bang like, out of nothing (no thing). We look at the soul. And much more!

The best way to review is to scan first the Aquinas’s original writing without my comments. For sticky points, then use my notes.

[2] Ch. xiii.
[3] Bk. II., ch. xv.
[4] Ch. xlvii.
[5] 8 Phys. i. 2; ix. 3.
[6] Ch. xxviii.
[7] D. 3. ii. 5.
[8] Ch. xxviii.
[9] 1 Phys. ix. 3.
[10] Sum. Th. P. I., Q. xiv., A. 11.
[11] D. 2. iv. 15.

April 12, 2015 | 2 Comments

Summary Against Modern Thought: God’s Understanding Is His Essence

This may be proved in three ways. The first...
This may be proved in three ways. The first…
See the first post in this series for an explanation and guide of our tour of Summa Contra Gentiles. All posts are under the category SAMT.

Previous post.

We’re entering an arcane patch, a thicket of argument to prove a technical point about God’s intelligence. I’ll skip around some of this material, but not all of it. We need it to get to the punchline, which is coming in 15 chapters, that God is Truth. From Truth we move to Good and Evil. So this thicket is well worth punching through, though I admit that some attentions will flag.

Chapter 46 That God Understands by Nothing Else but His Essence (alternate link)

[1] FROM what has been proved above it is made evident that the divine intellect understands by no other intelligible species but the divine essence.

Notes Think of “intelligible species” as the how of how God thinks. What Aquinas is doing is showing, or rather illuminating, a point he already proved, that God is simple (in the meaning of that technical term) way back starting in Chapter 18.

[2] For the intelligible species is the formal principle of the intellectual operation; even as the form of every agent is the principle of that agent’s proper operation. Now the intellectual operation of God is His essence, as we have shown.[1] Wherefore something else would be the principle and cause of the divine essence, if the divine intellect understood by some intelligible species other than His essence: and this is in contradiction with what has been shown above.[2]

Notes And this is the main point. A car operates by being in the form of a car, yes? And God operates by His form, His essence. A weak analogy would be to say that if God had a brain by which His intelligible species operated, He would have parts, which we have already proved He cannot. And we’d also have to explain how this “Brain of God” moved God’s intelligence around separate from His will. Sort of like how materialists have to prove the “Brain of Man” moves your intellect about separate from your will. The next two arguments illuminate this.

[3] Again. The intellect is made actually intelligent by the intelligible species: just as sense is made actually sentient by the sensible species. Hence the intelligible species is compared to the intellect as act to potentiality. And consequently if the divine intellect were to understand by a species other than itself, it would be in potentiality with respect to something: and this is impossible, as we have proved above.[3]

[4] Moreover. An intelligible species that is accessory to the essence of the intellect in which it is, has an accidental being: for which reason our knowledge is reckoned among the accidents. Now in God there can be no accident, as proved above.[4] Therefore there is no species in His intellect besides the divine essence…

Notes In [3] there is the proof, if you like, that animals are sentient, which means having the capability of sensing. This is only worth pointing out because of the modern understanding that all sentient creatures, including humans, are alike. This is so, but humans are not just sentient, but are also rational, possessing an intellect, and animals do not.

The second point is the ever-necessary distinction between act and potential. Only something in act, or that has actuality, can move a potential to act, i.e. can cause something to happen. In God there is no potentiality, in us there is. The second translation of [4] (linked above) puts it in better modern English, “an intelligible species in the intellect that is other than the intellect’s essence has an accidental being, which is why our knowledge is numbered among the accidents.” Some (I don’t think we can say all) of the knowledge we have is not essential to our being, but all of God’s knowledge is His essence.

[6] Moreover. God’s act of intelligence is His essence, as we have proved.[5] Therefore if He understood by a species that is not His essence, it would be by something other than His essence. But this is impossible.[6] Therefore He does not understand by a species that is not His essence.

Notes And that, I think, is enough for today. Review the terms act and potential, or actuality and potentiality, and form and accident. (All the posts in this category are found in the link at the top.) Next week it gets harder.


[1] Ch. xlv.
[2] Ch. xiii.
[3] Ch. xvi.
[4] Ch. xxiii.
[5] Ch. xlv.
[6] Ch. xxii.

April 5, 2015 | 6 Comments

Summary Against Modern Thought: God’s Intelligence Is His Essence

This may be proved in three ways. The first...
This may be proved in three ways. The first…
See the first post in this series for an explanation and guide of our tour of Summa Contra Gentiles. All posts are under the category SAMT.

Previous post.

He is risen! If you doubt that, see this.

Chapter 45 That God’s Act of Intelligence is His Essence (alternate link)

[1] FROM the fact that God is intelligent it follows that His act of intelligence is His essence.

[2] For intelligence is the act of an intelligent being, existing within that being and not passing on to something outside of it, as heating passes into the thing heated: for the intelligible suffers nothing through being understood, but the one who understands is perfected. Now whatever is in God is the divine essence.[1] Therefore God’s act of intelligence is the divine essence, the divine existence, and God Himself: since God is His essence and His existence.[2]

Note The obvious joke, understood by teachers everywhere, suggested by the first sentence, must be resisted. But another way to say it is that my teaching you gives you something while taking nothing from me. I don’t grow dumber while you gain smarts. We already know that God’s essence and existence are equivalent, and that God is intelligent, therefore intelligence is part of, or is, this essence.

[3] Further. The act of intelligence is compared to the intellect as existence to essence. But God’s existence is His essence, as proved above.[3] Therefore God’s act of intelligence is His intellect. Now the divine intellect is God’s essence, otherwise it would be accidental to God.[4] Therefore the divine act of intelligence must needs be His essence.

Note Don’t forget an accident need not be there. I can wear a hat or not, but either state is accidental to my humanity. Etc.

[4] Moreover. Second act is more perfect than first act, even as consideration is more perfect than knowledge. Now God’s knowledge or intellect is His very essence, if He is intelligent as shown above:[5] since no perfection belongs to Him by participation, but by essence, as already proved.[6] If, therefore, His act of consideration be not His essence, something will be more noble and perfect than His essence. And thus He will not be in the summit of perfection and goodness:[7] and consequently He will not be first.

Note First and second act? Here, para 10:

There are two types of acts in creatures, first act and second act. First act is the form and the act of existence that a form gives. Form is called the primarily first act, existence, the secondarily first act. Second act, however, is operation. Now, the first act of corporeal things comes directly from God. Therefore, their second acts are also caused directly by God. But the only way in which one thing governs another is by being in some manner the cause of its operations…

[5] Again. Intelligence is the act of the intelligent. If then God being intelligent is not His act of intelligence, He must be compared to it as potentiality to act: and so there will be potentiality and act in God; which is impossible, as we have proved above.[8]

[6] Again. Every substance is for the sake of its operation. If therefore God’s operation is other than the divine substance, His end will be other than Himself. And thus God will not be His own goodness, since the good of a thing is its end.[9]

[7] If, however, God’s act of intelligence is His existence, His act of intelligence must be simple, eternal, unchangeable, existing only in act, and all those things which have been proved about the divine existence. Wherefore God is not in potentiality to intelligence, nor does He begin to understand a thing anew, nor is His act of intelligence subject to any change or composition whatsoever.

Note A word about God’s unchanging nature. God acts, which appears to us who are stuck in time, to be changes in time. But God is outside time, and all is available to him. Therefore His acts are not potentialities becoming actualities, as they are with us. The analogy that God has already acted, and we’re just living out the consequences of these acts, must fail. There is no way for us to understand, truly comprehend, what it means to be outside time. God is simple (in the technical meaning of that term): He exists. I Am that I Am: I Will Be What I Will Be. We’ll come back to this subject in time (get it? get it?).


[1] Ch. xxiii.
[2] Chs. xxi., xxii.
[3] Ch. xxii.
[4] Cf. ch. xxiii.
[5] Ch. xliv.
[6] Ch. xxiii.
[7] Cf. ch. xxviii.
[8] Ch. xvi.
[9] Cf. Chs. xxxvii., xxxviii.

March 29, 2015 | 38 Comments

Summary Against Modern Thought: God Is Intelligent

This may be proved in three ways. The first...
This may be proved in three ways. The first…
See the first post in this series for an explanation and guide of our tour of Summa Contra Gentiles. All posts are under the category SAMT.

Previous post.

Saint Wiki is back! But in case it disappears again, I’ll keep running links to both our translations.

Chapter 44 That God is Intelligent (alternate link)

[1] IT may be shown from the above that God is an intelligent being.

[4] Moreover. In no order of movers do we find that a mover by the intellect is the instrument of that which moves without intellect; but rather the opposite. Now all movers that are in the world, are compared to the first mover which is God, as instruments to the principal agent. Since then we find in the world many movers by intellect, it is impossible that the first mover move without intellect. Therefore God must of necessity be intelligent.

Notes Did you notice we return to Chapter 13 more than any other? Review, review, review. If, as is true, God is (ever) the first mover, then He must be intelligent, because why? Because randomness certainly cannot be intelligent and causal (think about it).

[5] Again. A thing is intelligent from the fact of its being without matter: in sign of which forms become understood by being abstracted from matter. Hence also understanding is of universals and not of singulars, because matter is the principle of individualization. Now forms actually understood become one with the intellect actually understanding. Wherefore, if forms are actually understood from the very fact that they are without matter, it follows that a thing is actually intelligent from the fact that it is without matter. Now it was shown above[2] that God is absolutely immaterial. Therefore He is intelligent.

Note Not only God’s, but our intellects are also immaterial. We are not our brains. See this review of Feser’s The Last Superstition for more detail.

Consider first that when we grasp the nature, essence, or form of a thing, it is necessarily one and the same form, nature, or essence that exists both in the thing and in the intellect. The form of triangularity that exists in our minds when we think about triangles is the same form that exists in actual triangles themselves; the form of “dogness” that exists in our minds when we think about dogs is the same form that exists in actual dogs; and so forth. If this weren’t the case, then we just wouldn’t really be thinking about triangles, dogs, and the like, since to think about these things requires grasping what they are, and what they are is determined by their essence or form. But now suppose that the intellect is a material thing—some part of the brain, or whatever. Then for the form to exist in the intellect is for the form to exist in a certain material thing. But for a form to exist in a material thing is just for that material thing to be the kind of thing the form is a form of; for example, for the form of “dogness” to exist in a certain parcel of matter is just for that parcel of matter to be a dog. And in that case, if your intellect was just the same thing as some part of your brain, it follows that that part of your brain would become a dog whenever you thought about dogs. “But that’s absurd!” you say. Of course it is; that’s the point. Assuming that the intellect is material leads to such absurdity; hence the intellect is not material.

[7] Moreover. Whatever tends definitely to an end, either prescribes that end to itself, or that end is prescribed to it by another: else it would not tend to this end rather than to that. Now natural things tend to definite ends, for they do not pursue their natural purposes by chance, since in that case those purposes would not be realized always or for the most part, but seldom, for of such is chance. Since then they do not prescribe the end to themselves, for they do not apprehend the notion of end, it follows that the end is prescribed to them by another, Who is the author of nature. This is He Who gives being to all, and Who necessarily exists of Himself, Whom we call God, as shown above.[6] Now He would be unable to prescribe nature its end unless He were intelligent. Therefore God is intelligent…

Notes The acorn doesn’t know it’s heading towards and oak: it is merely fulfilling its genetic plan. If conditions are right. If they are not, then the acorn does not reach its end. Now we know that acorns become oaks and not Buicks or octopuses. If there was no regularity, there’d not only be no oaks, there’d be no us, thus there’d be no arguments on whether teleology was real.

It’s not only acorns that move toward ends but photons in double-slit experiments, too. Those photons don’t become kumquats or icicles, but move in regular, predictable patterns—as if they had an end, which they do. Slide from acorns to photons to whatever is smaller or more basic. It will be the same story. Ends are being met. And those ends could not be caused by “chance”, which cannot be a cause. At base, there must be a first mover, first cause, that designs the ends which are met. There is no other way to produce regularity. The “laws” which govern the universe (all there is) must come from an intelligence; they cannot come from nothing or “blind chance”, which isn’t a power.

So we’re right back at Chapter 13 again. Plus, it doesn’t seem likely that most people would argue God is not intelligent (though they do incorrectly argue He doesn’t exist).


[1] Ch. xiii.
[2] Chs. xvii., xx., xxvii.
[3] Ch. xxviii.
[4] Ch. xxxi.
[5] 3 De Anima viii. 1.
[6] Ch. xiii.
[7] Ps. cxxxviii. 6.