Chapter XVI. Question 16 or trutu summary of doctrine

St. Tuomas first treats of truth in genera! and then of divine truth. Concerning truth in general he considers it in its threefold relationship: (1) to the intellect by which it is known or manifested; (2) to being on which it is founded; (3) to good which follows as a property of being. These questions are treated at length in metaphysics, so that we shall not devote much time to them.

In the first article it is shown that truth resides formally and primarily in the intellect and secondarily in things as they relate to the intellect. But things are measured by the divine intellect and by the divine ideas, and they measure our intellect, which is said to be true in so far as it is in conformity with them. Thus “a stone is called true which possesses the nature proper to a stone, according to the preconception in the divine intellect.” 1

In the second article it is shown that the conformity or identity between our intellect and the thing can indeed already be present in the intellectual act of simple apprehension by way of a representation that expresses conformity with the thing. But a conformity as known and compared with the thing, is found only in the act of judgment, or in the intellect composing and dividing, because it is there that the conformity or non-conformity of the predicate with the subject is first clearly seen, inasmuch as it is true to say that a thing is what it is, and is not what it is not; and that it is false to say that a thing is what it is not, and is not what it is.

The third article determines the relation of truth to being. Truth as found in things ig convertible with being, entitatively or according to substance, by adding relation to the intellect, such as true gold. But truth as found in the intellect is not convertible with being entitatively, but manifestatively, as the manifestator is with the thing manifested, or regulatively, as the regulator is with the thing regulated. Thus the intellect is rue when judging of a thing or regulating what must be regulated.

The fourth article concerns the relation of truth to goodness. It is stated that, although the true and the good are the same entitatively, yet in their formal aspects the true is prior to the good, because the true has its foundation in the being of the thing, according to its very essence; but the good has its foundation in the thing according as it is perfect and desirable. Similarly, the true refers to knowledge, which is prior to the appetite, to which good refers; for nothing is willed that is not foreknown.

The second part of the question is about divine truth, namely, how it exists in God; and from divine truth it is shown that truth is one, eternal, and immutable.

The fifth article shows that God is not only true, but is Truth itself, because His being is not only conformed to His intellect, but is the very subsistent act of His intellect. Moreover, God is the supreme truth, because His act of understanding is the cause of every other being and intellect. Thus God is the first truth in the ontological, logical, and moral orders, in that it is impossible for God to lie.

The sixth article explains that truth which is absolutely one, is found only in the divine intellect, which is the measure of all things; but in creatures there are as many ontological truths as there are entities, and as many formal truths as there are things known to be true.

The seventh article shows that the positively eternal truth is found only in the divine intellect, which alone is eternal; but negatively some things are said to be of eternal truth, because they abstract from circumstances of place and time. Such are the principles of contradiction, causality . . . , and all necessary propositions. But the formal or cognitive truth of these statements is eternal only in the divine intellect, in that God alone knows from eternity these necessary truths.

Therefore we must not overlook what St. Thomas says in another of his works: “From the fact that truths known by the intellect are eternal with regard to what is thus known, one cannot conclude that the soul is eternal, but that the truths known have their foundation in something eternal. They have their foundation in that first Truth which, as the universal cause, contains within itself all truth.” ?

This is the proof of God's existence founded on the eternal verities, and it is referred back to the fourth proof of St. Thomas,’ in that it ascends from different degrees of truth until it reaches the maximum truth. For it is evident that an absolutely necessary

principle, such as the principle of contradiction, by which all actual and possible beings and all our intelligences are necessarily regulated, must have its foundation in some necessary and supreme Being and in some supreme and eternal Intellect. For this absolutely necessary principle, such as the principle of contradiction, cannot have its foundation in some contingent existence, or in a multiplicity of such contingent existences, for all these come under the law of this principle; but this necessary and negatively eternal truth postulates as its ultimate foundation one that is necessarily and positively eternal.

Finally, the eighth article shows that the truth of the divine intellect is immutable, whereas our intellect changes from truth to falsity; and this happens in two ways: (1) when one gets a wrong opinion about something which in itself has not changed; or (2) when the thing is changed, but not the opinion.*

4St. Thomas says in the body of this article: “The truth of our intellect is mutable, not because it is itself the subject of change, but in so far as our intellect changes from truth to falsity.” Thus necessary truths, especially first principles, do not change. It is likewise always true that a thing was such as it once was. But our intellect, even in its judgment of immutable truths, sometimes undergoes a change, and this is because of its debility, that is, because of its want of consideration or forgetfulness.

At the end of the argumentative part of the article he says: “The truth, however, of the divine intellect is that according to which natural things are said to be true, and this is altogether immutable.” This statement affirms both the immutability of the divine intellect and the immutable nature of things, which correspond to the divine ideas. Thus, too, for us truths which strictly pertain to the very natures of things, such as “man is a rational animal,” are immutable and negatively eternal, inasmuch as they abstract from circumstances of place and time.