Commentaria in Summam contra Gentiles, Liber I

Second, he shows that in God there is no habitual cognition ¹.

I. And he argues first as follows. God knows all things simultaneously in act. Therefore His knowledge is not habitual. — The consequence is evident. For where knowledge is habitual, some things are known by habit alone, and not in act.

Second. The divine intellect is in no way in potency. Therefore, etc. — The consequence is evident. For one who possesses a habit and is not considering it is in potency in a certain way: namely, accidentally, but not essentially.

Third. In God, operation is his essence. Therefore, etc. — The consequence is proved. Because wherever the intellect knows habitually, there essence and actual operation are distinct things: for one who knows habitually lacks actual consideration, in this way; but essence cannot be lacking to him.

Fourth. If this were so, God would not be universally perfect. — The consequence is proved. Because an intellect knowing habitually is not in its ultimate perfection, namely with respect to the genus of intellect as such. Hence neither does the Philosopher place happiness in habit, but in act.

Fifth ². There are not in the divine intellect any species superadded. Therefore, etc. — The consequence is proved: because every intellect in habit understands by means of certain species; for a habit is either a certain aptitude for receiving intelligible species, or it is an ordered aggregation of those intelligible species themselves existing in the intellect in a middle way between act and potency.

II. It must be noted that Saint Thomas here speaks of the habit of science under a disjunction, on account of the various opinions concerning it. For Avicenna, as is said in De Veritate, q. XII, a. 1, and IV Sent., d. L, a. 2 ³, held that the habit of science is a certain aptitude of our soul for receiving the illumination of the agent intelligence and the intelligible species flowing from it ⁴. — Others, however, said that the habit of science is a collection of species. — Saint Thomas, however, sometimes seems to say that its esse is a certain simple quality, as in Prima Secundae, q. LIV, a. 4; at other times that it is a collection of many species, as in De Veritate, q. XX, a. 2.

I would say, for the exposition of the opinion of St. Thomas, that we can speak of the scientific habit of our intellect in two ways: namely, formally; and fundamentally, or originatively. If we speak fundamentally and originatively, it is a collection of the very species themselves. For the intellect cannot consider any conclusions unless it be in act through intelligible species abstracted from phantasms by the power of the agent intellect. — But because one who has such species cannot use them in an orderly and scientific manner except through exercise in demonstrations made from those species, from which there is caused in the intellect a certain quality by which the intellect is apt for considering the conclusions of one science promptly and with delight; therefore this very aptitude is what is essential and formal in the scientific habit, understanding by "aptitude" not merely a habitude and relation, but a quality by which the intellect becomes proximately apt for using the intelligible species and for considering the conclusions of a science. On account of this St. Thomas says ⁵ that habit is a collection of ordered species: namely, because those very species do not have the character of a scientific habit unless that very aptitude by which they are ordered in the intellect with respect to their use supervenes upon them.

Hence knowledge is said to be the effect of demonstration with respect to its esse ⁶, not indeed with respect to the very foundation, because intelligible species are not caused by the work of the possible intellect, of which kind is demonstration, but by the act of the agent intellect; but with respect to the formal element, namely with respect to aptitude. For by demonstration the intellect is rendered apt for using the intelligible species with respect to the demonstrated conclusion. And because by one demonstration concerning one genus of intelligibles an aptitude is caused in the intellect for considering by means of the species of that genus, therefore by other demonstrations concerning the same genus no new quality and new aptitude is caused; rather, what was caused before is extended and perfected, insofar as the intellect is thereby made apt for considering more conclusions concerning the same intelligible genus, to which it was previously in potency only, according to what Saint Thomas says in the Prima Secundae ⁷.

Similarly we may say that in the angelic intellect the species themselves exist fundamentally, while formally there is a certain aptitude for using those species—whether this is something distinct in them from the intellect itself, or whether it is the natural light of the intellect.

Other Thomists treat this difficulty most fully. Therefore what has been said about it by us in this place may suffice.

III. Sixth. In God there is no quality. Therefore, etc. — The consequence is evident, because a habit is a quality.

It must be considered, from the doctrine of St. Thomas, I Sent., d. xxxv⁸, and the First Part, q. xiv⁹, that since knowledge signifies perfection by reason of certainty, but imperfection insofar as it is a quality and insofar as it involves a process of reasoning; just as other things are said of God through the removal of all imperfection, so too, when knowledge is attributed to God, it is attributed to him by reason of certainty, but not by reason of quality or discursiveness. And because we are speaking here of a habit properly so called, to which it belongs that it be a quality, therefore it is said here absolutely that a habit is a quality.

It is finally confirmed by the authority of the Psalm, "He who keeps Israel shall neither slumber nor sleep": because the disposition of one habitually knowing is assimilated to the disposition of one sleeping, as is said in XII Metaphysics, commentary L. ¹⁰ — Likewise by the authority of Ecclesiasticus xxiii, "The eyes of the Lord" etc.