Metaphysics

​Since it is possible for there to be something intermediate between contraries, and in some cases there is, the intermediates must be composed of the contraries. For all intermediates are in the same genus as those things of which they are intermediates. For we call those things intermediate into which that which changes must change prior [to reaching the extremity] (for example, if one were to pass from the lowest note to the highest note by the smallest interval, one will come first to the intermediate notes; and in colors, if one passes from white to black, one will come first to red and grey than to black; and similarly in other cases too); but it is not possible to change from one genus to another genus except accidentally, as for instance from color to shape. Therefore, it is necessary that the intermediates be in the same genus both with themselves and with those things of which they are intermediate. But indeed, all intermediates are intermediates of certain opposites; for it is only from these that change is possible in itself (which is why it is impossible for there to be an intermediate of things that are not opposite; for then there would be change even from things that are not opposite). Now of opposites, there is no intermediate of contradiction (for this is contradiction: an opposition in which one or the other of the parts is present to anything whatever, having nothing intermediate); but of the remaining, some are relatives, some are privation, and some are contraries. And of relatives, those which are not contraries have no intermediate; and the reason is that they are not in the same genus. For what is intermediate between knowledge and the knowable? But there is between the great and the small. But if the intermediates are in the same genus, as has been shown, and are between contraries, they must be composed of these contraries. For either there will be some genus of them or none. And on the one hand, if there is to be a genus in such a way as to be prior to the contraries, the prior differences which produce the contrary species of the genus will be contraries; for the species come from the genus and the differences (for example, if white and black are contraries, and one is dispersive color and the other compressive color, these differences— dispersive and compressive—are prior; so these are prior contraries to one another). But indeed, those things which differ contrarily are contraries in a higher degree; and the rest and the intermediates will consist of the genus and the differences (for example, as many colors as are intermediate between white and black, these must be spoken of as consisting both of the genus —and the genus is color—and of certain differences; but these differences will not be the primary contraries; otherwise, each intermediate would be either white or black; therefore they are other differences; hence these differences will be intermediate between the primary contraries, and the primary differences are the dispersive and the compressive); hence we must first investigate, in the case of all those contraries which are not in a genus, what their intermediates are composed of (for things in the same genus must either be composed of the simple elements in the genus or be simple themselves). Now, contraries are not composed of one another, so they are principles; but the intermediates are either all composite or none is. But something comes to be out of the contraries, so there will be change into this prior to changing into the contraries themselves; for of each of the two, it will have both less and more. Therefore, this too will be intermediate between the contraries. And therefore all the other intermediates too are composite; for that which is more of one and less of the other is in some way composite of those things of which it is said to be more of one and less of the other. And since there are no other prior things of the same genus as the contraries, all the intermediates must be composed of the contraries; hence all the lower things also, both the contraries and the intermediates, will consist of the primary contraries. That, then, all the intermediates are in the same genus, and are between contraries, and are all composed of the contraries, is clear.