Commentaria in Summam contra Gentiles, Liber II

The second conclusion is ¹: The distinction of things is not on account of the diversity of matter as on account of its first cause. Here it must be noted that this conclusion is advanced not only against those who posit matter alone as a cause, but also against those who posit, together with matter, an efficient cause, while nevertheless holding that matter is presupposed to the distinction of things, from which the distinction is first caused in things.

I. It is argued first against this opinion as follows. From matter nothing can come forth except by chance. But the distinction of things is not from chance. Therefore, etc. — The major premise is proved: because, since matter is possible with respect to many things, its determination to one happens the more rarely; and such a thing is what occurs by chance, especially when the intention of the agent is removed.

It must be noted, for this reason, that when it is said that nothing can come from matter except by chance, this must be understood of that which comes from matter as from a first cause; but not of that which comes from matter according to the disposition of an agent. For if matter itself were posited as the first cause, it would be a cause removed from intention even in respect of the agent's intention, at least according to the mode of understanding. Therefore, since it is in itself indifferent to many things, that one determinate thing should come from it will be only in fewer cases and by chance: because it does not come from any intention of an agent.

II. Second. Forms do not follow the disposition of matter as from a first cause, but rather the reverse: matters are so disposed that they may be such forms. Therefore neither is there a distinction of species. — The consequence is evident. For the distinction of things according to species is through forms. — The antecedent is proved. Because form is from the intention of the agent. But those things which are from the intention of the agent are not from matter as from a first cause. Then also because the agent cause is prior in causing than matter. Then also because we see that those things which are reduced to matter as to a first cause, like monsters, are contrary to the intention of the agent.

Note, from Book IV of the Sentences, distinction xxxvi, question 1, ad 2, that monsters, although they arise beyond the first intention of the agent nature, are nevertheless not against its second intention. For when nature cannot lead a thing to greater perfection, it leads it to lesser perfection, and to that which it can.

2. But a doubt arises concerning what is said: forms do not follow the dispositions of matter, but rather the reverse. For according to the teaching of Saint Thomas ², designated matter is the principle of individuation in material things. Therefore forms are distinguished because they are received into different matters. Therefore forms follow the dispositions of matter.

It can be answered first, that Saint Thomas in this place speaks of the formal and specific distinction, in the way in which the essential parts of the universe are distinguished: but not of a material distinction.

Second, it can be answered that forms indeed receive individuation, or even distinction, from designated matter; and therefore they require that they have matters disposed and proportioned to them. But it does not follow that they must follow the dispositions of matter as the primary causes of distinction, just as a thing ordered to an end does not follow the disposition of the end.

Nay, rather: because the agent intends to produce a form that is limited and individuated, it disposes the matter so that it may be proportionate to a form thus limited.

Hence the first consequence is denied, if it is inferred concerning the first cause of the distinction of forms: although it is true, speaking of a secondary cause. For the agent is the first cause of individuation, because it intends to produce a singular and individuated form; matter, however, is the secondary cause, inasmuch as the agent, intending by its action to produce this form, disposes matter so that it may be suitable for such a form. — But when it is inferred, Therefore forms follow the dispositions of matter, this is granted if the sense concerns the order in which the end follows those things that are for the sake of the end according to the order of execution; but the following is denied with respect to the order in which what is ordered to an end follows the end according to the order of the agent's intention.

III. Third. Many things are distinct from one another in things that cannot be made from preexistent matter. Therefore, etc. — The consequence is evident. For the distinction of things cannot arise from matter except in those things which are made from preexistent matter.

Fourth. It is supposed that, if matter is the cause of distinction, one must hold that matters are distinct in themselves. Then thus: something else is the cause of the distinction of matters, because they have a cause of their esse; but things that have a cause of their esse and are thereby distinguished also have a cause of their distinction. Therefore the first cause of the distinction of things cannot be the diversity of matter.

Fifth. All things proceed from God through the agent intellect. Therefore they are from God, lesser things on account of better ones. Hence He produced matter for the sake of forms, and not conversely. Hence the distinction of species in things, which is through forms, is not on account of matter; rather, matters were created distinct so as to be suited to diverse forms. — The first inference is proved: because both intellect and nature act for the sake of what is better by means of what is lesser, and not conversely, since they act for the sake of the good. — The second is also evident: because form is nobler than matter.

By this, however, Saint Thomas says, the opinion of Anaxagoras is excluded.

Here it must be noted that, although Anaxagoras posited an agent cause, he nevertheless wished the distinction of material parts to be presupposed to the distinction of things, so that the first cause of distinction in things would be the distinction of those material parts: as if the agent could not produce distinct things unless those distinct natural parts preexisted. That this is plainly false has been shown from the preceding arguments.