(4) Whether the separate soul of man can move bodies by local movement? _______________________
FIRST ARTICLE [I, Q. 117, Art. 1]
Whether One Man Can Teach Another?
Objection 1: It would seem that one man cannot teach another. For the Lord says (Matt. 22:8): "Be not you called Rabbi": on which the gloss of Jerome says, "Lest you give to men the honor due to God." Therefore to be a master is properly an honor due to God. But it belongs to a master to teach. Therefore man cannot teach, and this is proper to God.
Obj. 2: Further, if one man teaches another this is only inasmuch as he acts through his own knowledge, so as to cause knowledge in the other. But a quality through which anyone acts so as to produce his like, is an active quality. Therefore it follows that knowledge is an active quality just as heat is.
Obj. 3: Further, for knowledge we require intellectual light, and the species of the thing understood. But a man cannot cause either of these in another man. Therefore a man cannot by teaching cause knowledge in another man.
Obj. 4: Further, the teacher does nothing in regard to a disciple save to propose to him certain signs, so as to signify something by words or gestures. But it is not possible to teach anyone so as to cause knowledge in him, by putting signs before him. For these are signs either of things that he knows, or of things he does not know. If of things that he knows, he to whom these signs are proposed is already in the possession of knowledge, and does not acquire it from the master. If they are signs of things that he does not know, he can learn nothing therefrom: for instance, if one were to speak Greek to a man who only knows Latin, he would learn nothing thereby. Therefore in no way can a man cause knowledge in another by teaching him.
On the contrary, The Apostle says (1 Tim. 2:7): "Whereunto I am appointed a preacher and an apostle . . . a doctor of the Gentiles in faith and truth."
I answer that, On this question there have been various opinions. For Averroes, commenting on De Anima iii, maintains that all men have one passive intellect in common, as stated above (Q. 76, A. 2). From this it follows that the same intelligible species belong to all men. Consequently he held that one man does not cause another to have a knowledge distinct from that which he has himself; but that he communicates the identical knowledge which he has himself, by moving him to order rightly the phantasms in his soul, so that they be rightly disposed for intelligible apprehension. This opinion is true so far as knowledge is the same in disciple and master, if we consider the identity of the thing known: for the same objective truth is known by both of them. But so far as he maintains that all men have but one passive intellect, and the same intelligible species, differing only as to various phantasms, his opinion is false, as stated above (Q. 76, A. 2).
Besides this, there is the opinion of the Platonists, who held that our souls are possessed of knowledge from the very beginning, through the participation of separate forms, as stated above (Q. 84, AA. 3, 4); but that the soul is hindered, through its union with the body, from the free consideration of those things which it knows. According to this, the disciple does not acquire fresh knowledge from his master, but is roused by him to consider what he knows; so that to learn would be nothing else than to remember. In the same way they held that natural agents only dispose (matter) to receive forms, which matter acquires by a participation of separate substances. But against this we have proved above (Q. 79, A. 2; Q. 84, A. 3) that the passive intellect of the human soul is in pure potentiality to intelligible (species), as Aristotle says (De Anima iii, 4).