Thomas Aquinas

“ Hence, if no intellect were eternal, no truth would be eternal. Now because only the divine intellect is eternal, in it alone truth has eternity. Nor does it follow from this that anything else but God is eternal ”

“ Hence in one way truth varies on the part of the intellect, from the fact that a change of opinion occurs about a thing which in itself has not changed, and in another way, when the thing is changed, but not the opinion; and in either way there can be a change from true to false. If, then, there is an intellect wherein there can be no alternation of opinions, and the knowledge of which nothing can escape, in this is immutable truth. ”

“ The truth of our intellect is according to its conformity with its principle, that is to say, to the things from which it receives knowledge. The truth also of things is according to their conformity with their principle, namely, the divine intellect. ”

“ Further, it was always true that what is true in the present was to be in the future. But as the truth of a proposition regarding the present is a created truth, so is that of a proposition regarding the future. Therefore some created truth is eternal. ”

“ Now this cannot be said, properly speaking, of divine truth; unless perhaps in so far as truth is appropriated to the Son, Who has a principle. But if we speak of divine truth in its essence, we cannot understand this unless the affirmative must be resolved into the negative, as when one says: "the Father is of Himself, because He is not from another." Similarly, the divine truth can be called a "likeness to the principle," inasmuch as His existence is not dissimilar to His intellect. ”

“ That something is always and everywhere, can be understood in two ways. In one way, as having in itself the power of extension to all time and to all places, as it belongs to God to be everywhere and always. ”

“ The ancient philosophers held that the species of natural things did not proceed from any intellect, but were produced by chance. But as they saw that truth implies relation to intellect, they were compelled to base the truth of things on their relation to our intellect. ”

“ The will and the intellect mutually include one another: for the intellect understands the will, and the will wills the intellect to understand. So then, among things directed to the object of the will, are comprised also those that belong to the intellect; and conversely. Whence in the order of things desirable, good stands as the universal, and the true as the particular; whereas in the order of intelligible things the converse of the case. From the fact, then, that the true is a kind of good, it follows that the good is prior in the order of things desirable ”

“ Secondly, it is evident from the fact that knowledge naturally precedes appetite. Hence, since the true regards knowledge, but the good regards the appetite, the true must be prior in idea to the good. ”

“ The true and being are convertible terms. Hence just as being is not generated nor corrupted of itself, but accidentally, in so far as this being or that is corrupted or generated, as is said in Phys. i, so does truth change, not so as that no truth remains, but because that truth does not remain which was before. ”

“ But the true cannot be apprehended unless the idea of being be apprehended also; since being is included in the idea of the true. The case is the same if we compare the intelligible object with being. For being cannot be understood, unless being is intelligible. Yet being can be understood while its intelligibility is not understood. Similarly, being when understood is true, yet the true is not understood by understanding being. ”

“ In this manner all universals are said to be everywhere and always, in so far as universals are independent of place and time. It does not, however, follow from this that they are eternal, except in an intellect, if one exists that is eternal. ”