Of the word ΕΙ engraven over the gate of Apollo's temple at Delphi (11)

Passing by many other such like things, said I, I will produce only Plato; who says, that there is but one world, but that if this were not alone, so that there were others besides it, they would be in all five and no more. For indeed, though there is but this one only world, as Aristotle is also of opinion, yet this world is in some sort composed and assembled of five, of which one indeed is of earth, another of water, the third of fire, the fourth of air, and the fifth, being heaven, some call light and others the sky; and some also name this same the fifth essence, which alone of all, bodies is naturally carried about in a circle, and not of necessity or otherwise by accident. Wherefore Plato, knowing that, of the figures which are in Nature, there are five most excellent and perfect,—to wit, the pyramid, the cube, the octahedron, the icosahedron, and the dodecahedron,—has fitly accommodated each of them to each of these worlds or bodies.