Article 1 — Whether, besides philosophy, any further doctrine is required?

Objection 1: It seems that, besides the philosophical disciplines, we have no need of any further teaching. For man should not seek to know what is above reason: Seek not the things that are too high for thee (Eccl 3:22). But whatever is not above reason is fully treated of in the philosophical disciplines. Therefore any other teaching besides the philosophical disciplines seems superfluous.

Obj. 2: Further, a teaching can be concerned only with being, for nothing can be known, save what is true; and all that is, is true. But everything that is, is treated of in the philosophical disciplines—even God Himself, so that there is a part of philosophy called theology, or the divine science, as Aristotle has proved (Metaph. vi). Therefore, besides the philosophical disciplines, there is no need of any further teaching.

On the contrary, It is written (2 Tim 3:16): All Scripture inspired by God is useful for teaching, for reproving, for correcting, and for instructing in justice. Now Scripture, inspired by God, is no part of the philosophical disciplines, which were discovered by human reason. Therefore it is useful that besides the philosophical disciplines, there should be another science inspired by God.

I answer that, It was necessary for man’s salvation that there should be a teaching revealed by God beyond the philosophical disciplines, which are investigated by human reason.

First, indeed, because man is directed to God, as to an end that surpasses the grasp of his reason: The eye hath not seen, O God, besides Thee, what things Thou hast prepared for them that love Thee (Isa 64:4). But the end must first be known by men who are to direct their thoughts and actions to the end. Hence it was necessary for the salvation of man that certain truths which exceed human reason should be made known to him by divine revelation.

Even as regards those truths about God which human reason could have discovered, it was necessary that man should be taught by a divine revelation; because the truth about God such as reason could discover, would only be known by a few, and that after a long time, and with the admixture of many errors. Whereas man’s whole salvation, which is in God, depends upon the knowledge of this truth. Therefore, in order that the salvation of men might be brought about more fitly and more surely, it was necessary that they should be taught divine truths by divine revelation.

It was therefore necessary that besides philosophical science built up by reason, there should be a sacred science learned through revelation.

Reply Obj. 1: Although those things which are beyond man’s knowledge may not be sought for by man through his reason, nevertheless, once they are revealed by God, they must be accepted by faith. Hence the sacred text continues, For many things are shown to thee above the understanding of man (Eccl 3:25). And in this, the sacred science consists.

Reply Obj. 2: Sciences are differentiated according to the different ways that things are knowable. For the astronomer and the physicist both may prove the same conclusion, for instance that the earth is round: the astronomer by means of mathematics, i.e., abstracting from matter, and the physicist by means of matter itself. Hence nothing prevents those things which may be learned from the philosophical disciplines, so far as they can be known by the light of natural reason, from being considered by another science according as they are known by the light of divine revelation. Hence theology included in sacred doctrine differs in kind from that theology which is part of philosophy.