Parmenides (154)

Then one has the same age as all the others so that the absolute one, unless it is naturally contrary to nature, could not have come into being either before or after the others, but only simultaneously with them. And by this reasoning the one would be neither older nor younger than the others nor the others than the one, but of the same age; but by the previous reasoning the one would be both older and younger than the others, and likewise the others than the one.

Certainly.

In this state, then, it is and in this way it has come into being. But what about the one becoming older and younger than the others, and the others than the one, and becoming neither older nor younger? Is it the same with becoming as with being, or otherwise?

I cannot say.

But I can say as much as this, that even if one thing be older than another, it cannot become older by any greater difference in age than that which existed at first, nor if younger can it become younger by any greater difference; for the addition of equals to unequals, whether in time or anything else whatsoever, makes the difference always equal to that which existed at first.

Yes, of course.

Then that which exists can never become older or younger than that which exists, if the difference in age is always the same; but it is and has become older, and the other is and has become younger, but it does not become so.

True.

And the one, since it exists, never becomes either older or younger than the other things.

No, it does not.

But see whether they become older and younger in this way.

In what way?

Because the one was found to be older than the others, and the others than the one.

What then?

When the one is older than the others, it has come into being a longer time than the others.

Yes.

Then consider again. If we add an equal to a greater and to a less time, will the greater differ from the less by the same or by a smaller fraction?

By a smaller fraction.

Then the proportional difference in age which existed originally between the one and the others will not continue afterwards, but if an equal time be added to the one and the others, the difference in their ages will constantly diminish, will it not?

Yes.

And that which differs less in age from something than before becomes younger than before in relation to those things than which it formerly was older?

Yes, it becomes younger.

But if the one becomes younger, must not those other things in turn become older than formerly in relation to the one?

Certainly.