Meditations 4:21

If our souls survive, how does the air find room for them—all of them—since the beginning of time?

How does the earth find room for all the bodies buried in it since the beginning of time? They linger for whatever length of time, and then, through change and decomposition, make room for others. So too with the souls that inhabit the air. They linger a little, and then are changed—diffused and kindled into fire, absorbed into the logos from which all things spring, and so make room for new arrivals.

One possible answer.

But we shouldn't think only of the mass of buried bodies.

There are the ones consumed, on a daily basis, by us and by other animals. How many are swallowed up like that, entombed in the bodies of those nourished by them, and yet there is room for them all—converted into flesh and blood, transformed to air and fire.

How is the truth of this determined?

Through analysis: material and cause.