Of that Thing which is Beyond the World, and Whether it be a Vacuum or Not.
Pythagoras and his followers say that beyond the world there is a vacuum, into which and out of which the world hath its respiration. The Stoics, that there is a vacuum into which infinite space by a conflagration shall be dissolved. Posidonius, not an infinite vacuum, but as much as suffices for the dissolution of the world; and this he asserts in his first book concerning the Vacuum. Aristotle affirms, that a vacuum does not exist. Plato concludes that neither within nor without the world there is any vacuum.