Commentaria in Primam Partem Summae Theologiae

In the title a doubt arises: what purpose does this article serve in this place. For here the argument concerns the perfection of the divine substance in itself; therefore a question about the creature, such as this one is, ought not to be mixed in.

To this it is said that, although this question is verbally about the creature, according to its sense nevertheless it is about the perfection of the divine nature. For what is asked here is whether the perfection of the divine nature is so great that no creature can be like it in being (esse), or not. This indeed remained to be investigated, after it had been determined both what perfect nature is and what universally perfect nature is. – But note that it is not asked whether the divine perfection is so great that nothing can be like it: but that no creature. For the first pertains to the question concerning the plurality of gods, and will be treated in question XI; the second, however, belongs to this place.

II. In the body there are two points: first, likeness is distinguished; second, the question is answered. – As to the first, likeness is threefold: the first, according to a form of the same ratio and of the same mode; the second, according to a form of the same ratio, but not of the same mode; the third, according to a form, but neither of the same ratio nor of the same mode. – The distinction is proved. Likeness is a conformity in form; therefore it is multiplied according to the manner of communicating in form; therefore threefold, etc. All is evident from the text.

III. As to the second point, the responsive conclusion to the question is: Creatures are like God, not according to the same specific or generic nature, but according to a certain analogy.

This conclusion has four parts: the first affirmative, namely that they are like God; the second negative, namely not according to species; the third negative, namely nor according to genus; and the fourth affirmative, namely but according to some analogy. – And first, the first part is proved. Every agent acts through its own form; therefore there must be in the effect a likeness of the form of the agent. And then you may add: therefore the creature must be like God. The consequence is proved: because every agent acts so as to produce what is like itself insofar as it is an agent, that is, according to that which is for it the reason of acting. – Then, as to the second and third and fourth parts: because God is not an agent contained within a species or a genus, but the universal principle of all being (esse). – All things are clear from the text.

IV. In response to the last point, a doubt arises concerning the authority of Dionysius, since he distinguishes cause and caused against things of one order. For from this it follows either that cause and caused are universally of different orders, which is clearly false in univocal causes; or that it is ambiguous, because it is uncertain of what kind of cause and of what kind of caused he is speaking; or that it is badly done, because things of different orders ought to be distinguished against things of one order whether they are cause and caused or not—for this is incidental.

V. To this it is said that this artificial distinction is certain and formal, if rightly understood. For it is not false, but most true and necessary, that cause and caused are universally and formally of diverse orders. But we use the name cause and caused not for the relations or causalities themselves; rather for the thing which is the ground of causing, and likewise for the thing, or form, which the caused receives from the cause: for these things are the foundations of the likeness between caused and cause, as in all cases. The foundations of likeness between some things can therefore be related in two ways, as is said in the text. In one way, they may be of the same order, as this whiteness and that whiteness, and this animal and that animal, etc.: and thus likeness is a relation of parity, and mutual. In another way, one of them may formally, by its own account, be caused by the other, as the image of Socrates and Socrates (for dependence on Socrates does not accrue to the image of Socrates accidentally): and thus likeness is neither a relation of parity nor mutual, but is reduced to the third genus of relatives, set forth in Book V Metaphysics¹, on the knowing and the knowable, etc. Now it is evident that cause and caused of this kind are of diverse orders. For it is impossible for things of the same order to be so related that dependence on the other belongs to the formal account of one: since whatever belongs to the account of one belongs to the account of the other, and conversely.

VI. Whence the answer to the objection concerning univocal causes is evident². For where there is univocation, there is not cause and caused formally and per se, but only materially and per accidens: since the form of the effect does not formally depend upon the form of the cause. For humanity as it is in Socrates, taken formally, does not depend in its being or in its coming-to-be upon the humanity of Plato his father: but the humanity of Socrates, because it is this, therefore depends on the father. And consequently the humanity which is the foundation of the likeness between father and son is not of the genus of cause or caused, except materially and per accidens: rather it is of the genus of foundations of the same order. Whatever things, therefore, taken formally, are cause and caused are foundations of likeness belonging to different orders, as is subtly brought forward in the text: and consequently between them there is a likeness of imitation, and not of pure likeness: and for this reason it is not mutual.

And note this well, and apply it proportionally to the matter concerning non-mutual relatives.