There is a nature mutable in space and time, namely body. And there is a nature which is not at all mutable in space, but only in time is it also mutable, namely soul. And there is a nature which cannot be changed in space or in time, and this is God. What I have suggested here is mutable in any way, is called creature; what is immutable is the Creator.
Now, since everything that we say exists, we would say exists insofar as it remains and insofar as it is one thing, and moreover unity is the form of all beauty, you can see in this arrangement of natures what is highest, what is lowest (and yet still exists) and what is in the middle, greater than the lowest and less than the highest.
The highest is Happiness itself; the lowest is that which can be neither happy nor miserable; but the middle nature lives in misery when inclined toward the lowest, in happiness when turned toward the highest. Whoever believes Christ does not love the lowest, is not proud in the middle, and thus is made capable of clinging to the highest—and that is all we are commanded, admonished, incited to do.
[46.1] Plato, it is maintained, was the first to speak of Ideas. Yet it is not the case that if this name did not exist before he instituted it, then the things themselves, which he called Ideas, did not exist, or that no one understood them. Rather, some called them perhaps by one name and others by another. For anyone can impose whatever name they wish on an unfamiliar thing which has no name in common use.
Now, it is not likely that there were no wise men before Plato, or that they did not understand whatever these things are that Plato, as was said, called Ideas—especially as such power is vested in them that no one can be a wise man without understanding them. Also, there were probably wise men in other nations besides Greece-something that Plato himself not only has sufficiently attested by traveling to perfect his wisdom, but also recorded in his books. So they (if there were any) should not be considered ignorant of the Ideas, even though perhaps they called them by another name. But so much for the name; let us look at the thing, which is what is most important to consider and become acquainted with, since words are assigned on the authority that everyone has to name the thing they have come to know however they want.
[46.2] Ideas, then, we can call in Latin “Forms” or “Species,” if we want to render it word for word. But if we call them Reasons [rationes], we are of course departing from strict translation (for Reasons are called logoi in Greek, not “Ideas”), yet anyone who wanted to use this word would not be straying far from the thing itself.
For the Ideas are certain original Forms or Reasons of things—fixed and immutable, not themselves formed, and therefore eternal, being always the same way—which are contained in the divine intelligence. And while they never come into being or pass away, everything that can come into being or pass away is said to be formed in accordance with them, as well as everything that does come into being and pass away.
But the soul is denied the ability to see them, except the rational soul, with that part of itself by which it is superior, that is, the mind itself or reason—as if with a kind of inner, intelligible face or eye of its own. And as a matter of fact, not even any and every rational soul is held to be capable of this vision, but rather those which are holy and pure, that is, those which have kept that eye which sees them healthy, whole, undisturbed, and like to the things it aims to see.
Now what person who is religious, and imbued with true religion, even though not yet able to see them, would venture to deny—indeed would not rather affirm—that everything which exists (i.e., whatever is included in some nature appropriate to its own kind, in order to exist) is produced by God as its author, and that by the same author everything that is alive lives, and that the universal preservation of things—that very order by which things that change repeat their temporal courses in a certain controlled way—is held together and governed by the laws of the most high God?
This being established or granted, who would venture to say that God fashioned all things irrationally? And if that cannot rightly be said or believed, then it follows that all things arc fashioned by Reason. And not the same Reason for a human being as for a horse—to think so is absurd. Hence individual things are created by Reasons appropriate to them.
And where are these Reasons supposed to be, but in the very mind of the Creator? For he was not looking at something located outside himself to set up what he set up in accordance with it—to believe that is sacriledge.
So if these Reasons of everything to be created (and everything already created) are contained in the divine mind, and nothing can be in the divine mind without being eternal and immutable, and these original Reasons of things are also what Plato called Ideas—then not only do Ideas exist, but they are true, for they are eternal, remaining the same way and immutable, and whatever exists is the way that it is by sharing [participatione] in them.
But the rational soul stands out above all the things God has fashioned, and it is closest to God when it is pure, cleaving to him in charity the more it perceives these Reasons (illuminated and saturated as it were by the intelligible light from him) not with bodily eyes, but with that chief part of itself by which it is superior, that is, with its intelligence—a vision which makes it utterly happy.
These Reasons, as was said, can be called Ideas, Forms, Species or Reasons; and it is allowed for many to call them whatever they want, but for very few to see what is true.