"In Chapter 1 of On the Heavens, Aristotle defines "body" and then notoriously ruptures dynamics by introducing a fifth element, beyond Plato's four, to explain the rotation of the heavens, which, like nearly all Greeks, Aristotle took to be real, not apparent. Even a member of his school, Xenarchus, we are told, rejected his fifth element. The Neoplatonist Simplicius seeks to harmonize Plato and Aristotle. Plato, he says, thought that the heavens were composed of all four elements but with the purest kind of fire, namely light, predominating. That Plato would not mind this being called a fifth element is shown by his associating with the heavens the fifth of the five convex regular solids recognized by geometry."--BOOK JACKET.Title Summary field provided by Blackwell North America, Inc. All Rights Reserved