Commentaria in Primam Partem Summae Theologiae

In the title, note that, from the conditions said to belong to God in the preceding article¹, in proving his esse it is clearly evident that it cannot enter anyone's mind that God's being is an accident; rather he must be a substance. Therefore, once the question whether he is has been settled—by which it is known that God is an ens—and from what is attached to it it plainly stands firm that he is a substance, he now immediately inquires whether he is a body, that is, whether he is a corporeal substance; so that the word "body" here is taken properly for a body that falls under the category of substance; whether that be a simple thing, as Averroes believes² concerning the heavenly body, or whether it is not found to be simple, is of no concern. Now this kind of substance, according to all, has threefold dimension annexed to it, whether that threefold dimension be identical with the substance itself or not. For neither of these alters the point at issue. But corporeal substance taken in this way is distinguished not only against the incorporeal, namely immaterial substance: but also against the non-body, that is, even the form which is the act of the body. For neither of these is a corporeal substance, since the word "corporeal" is the intrinsic difference constituting a body: although natural forms are called corporeal substances denominatively from the bodies whose forms they are. And thus "body" is taken properly, as is clear in II de Anima, at the beginning, where Aristotle asks whether the soul is a body. And it is taken in this way here, as appears with singular force also against the obstinate from the third argument brought forward in the text.

The sense of the title is therefore: whether God is a body, that is, a substance which truly and properly is quantified, or extended; or whether He is not, but rather either wholly inextended, or extended in act, or distinguished from corporeity in any other way whatsoever.

II. On the body, one responsive conclusion, negative with respect to the question: God is not a body. – It is proved in three ways³. First. God is the first unmoved mover: therefore He is not a body. The antecedent is evident from the preceding article. The consequence is proved: because no body is an unmoved mover. Which is proved inductively.

III. Concerning that proposition, no body moves what is not moved, note that it can be understood in two ways. First, by taking ly "not moved" actually or potentially. And thus it is evident, and is truly shown inductively. And thus it accords with the minor premise, namely God is an unmoved mover: and the intended conclusion is obtained. – Second, by taking ly "not moved" actually. And thus the proposition has a difficulty: nor does it appear inductively, but it needs argument and qualification. For induction is opposed by the fact that an unmoved magnet attracts iron, and unmoved snow chills, and color alters sight, etc. Hence, in my judgment, it is taken here in the first way.

Yet it is also true in a second way, when speaking of motion that is purely local. And its reason is assigned in I Contra Gentiles, chapter 20: because the mover must be together with the thing moved. For from this it evidently follows that the body moving cannot remain, while the body moved changes place: since if only the thing moved changes place, it ceases to be together with the moving body, which is supposed to remain in the place contiguous to that place from which the mover moves the thing moved.

And from this the exclusion of the instances is apparent: for they were not about purely local motion. And as for the others, it is evident. But concerning the magnet and similar things, you have from Averroes, VII Physics, commentary 10, that these things do not move, but other things are moved toward them: although not from everywhere, on account of the privation of the disposition, which they acquire from them in a certain place by way of a spiritual alteration. But concerning these things, when there will be discussion of the dependence of the other motions upon the motion of the heavens, more will be said⁴: now these things suffice here, where the argument proceeds from local motion.

IV. Second⁵. God is the first being (ens): therefore He is pure act: therefore He is not a body. – The antecedent is clear from the preceding article. The first inference is proved as follows. Act is simply prior to potency: therefore the first being (ens) is act without potency, which is to be pure act. The assumption is explained by showing the difference of order between act and potency considered absolutely, and act and potency with respect to something to which both belong: namely, that in this respect potency is prior; but absolutely—not in this or in that—act is prior. This is proved because whatever is in potency is not reduced to act except by some being (ens) in act. – But the second inference is proved thus: every body is continuous, in whose definition falls potency to division; for it is divisible into ever-divisible parts, as is said in Book VI of the Physics⁶.

V. Third. God is the noblest of all beings: therefore He is not a body. – The antecedent is evident from the preceding article. The consequence is proved: because it is repugnant to a body to be the noblest of all. Which is proved as follows. A body is either living or non-living: but neither is the noblest: for the living surpasses the non-living, and that by which it lives surpasses the living. That this is something other than a body is proved thus: because a body, insofar as it is a body, does not live; otherwise every body would live. – All things are clear.

VI. Nevertheless, at the insistence of certain people, the proposition a living thing is nobler than a non-living thing does not seem true to some: because it would follow that an ant would be nobler than a heavenly body, which is commonly held not to live.

To this it is said that the heavenly body is perhaps alive, in truth. And yet if it is compared to an ant, not insofar as it lives, but insofar as it is a heavenly body, the answer is easy. For it will be said that the ant, as living, is nobler than the heavenly body considered apart from life. And this is necessary: because this is nothing other than to say that the soul is nobler than any body whatsoever; for the whole order of souls is above the whole order of bodies, as is evident.

But if, according to the truth of the matter, the heaven is not living, then the answer becomes more difficult. For it cannot be said that this comparison is true in a qualified sense, and not simply—that is, that a living thing as such is nobler than a non-living thing as such. First, because this comparison would be puerile: since a stone as such is also nobler than a non-stone as such, and universally every positive thing is nobler than its negation. Second, because the point at issue would not be achieved. For he intends to destroy the claim that God is within the breadth of bodies, because life is nobler than corporeity. Now it is evident that the vital grade in the universe is superior to the grade of nature, insofar as nature is distinguished against soul, and that corporeity, according to its entire breadth, is enclosed within the order of life. Therefore not in a qualified sense, but simply, the whole breadth of body is below the breadth of life. And for this reason, if God is the most noble being, He cannot be a body: because there is given a higher order, namely the vital, in which living things are evidently found to exist.

It must therefore be said that living things are simply nobler than non-living things, as the argument brought forward makes clear, and as is stated in XVI de Animalibus⁷; and that, if heaven is not living, then an ant is a being (ens) simply nobler than heaven. Heaven, however, is a nobler body than an ant: and on account of this nobility in the genus of bodies, many relative nobilities with respect to life belong to it, such as incorruptibility, etc.

Aristotle, however, in VI Ethics ⁸, says that the heavenly bodies are more noble even than man, because he holds them to be living; as he expressly says must be supposed in II On the Heavens ⁹.