Then that which is, cannot become older or younger than that which is, since the difference of age is always the same; the one is and has become older and the other younger; but they are no longer becoming so. True. And the one which is does not therefore become either older or younger than the others which are. No. But consider whether they may not become older and younger in another way. In what way? Just as the one was proven to be older than the others and the others than the one. And what of that? If the one is older than the others, has come into being a longer time than the others. Yes. But consider again; if we add equal time to a greater and a less time, will the greater differ from the less time by an equal or by a smaller portion than before? By a smaller portion. Then the difference between the age of the one and the age of the others will not be afterwards so great as at first, but if an equal time be added to both of them they will differ less and less in age? Yes. And that which differs in age from some other less than formerly, from being older will become younger in relation to that other than which it was older? Yes, younger. And if the one becomes younger the others aforesaid will become older than they were before, in relation to the one. Certainly. Then that which had become younger becomes older relatively to that which previously had become and was older; it never really is older, but is always becoming, for the one is always growing on the side of youth and the other on the side of age. And in like manner the older is always in process of becoming younger than the younger; for as they are always going in opposite directions they become in ways the opposite to one another, the younger older than the older, and the older younger than the younger. They cannot, however, have become; for if they had already become they would be and not merely become. But that is impossible; for they are always becoming both older and younger than one another: the one becomes younger than the others because it was seen to be older and prior, and the others become older than the one because they came into being later; and in the same way the others are in the same relation to the one, because they were seen to be older, and prior to the one. That is clear. Inasmuch then, one thing does not become older or younger than another, in that they always differ from each other by an equal number, the one cannot become older or younger than the others, nor the others than the one; but inasmuch as that which came into being earlier and that which came into being later must continually differ from each other by a different portion--in this point of view the others must become older and younger than the one, and the one than the others. Certainly. For all these reasons, then, the one is and becomes older and younger than itself and the others, and neither is nor becomes older or younger than itself or the others. Certainly.