Ocellus Lucanus on the nature of the universe

by Julius Firmicus Maternus; Proclus; Tauros

THEOREM 3.

Things which are naturally moved in a circle, neither participate of gravity nor levity.

Demonstration.—For if AB is either heavy or light, it is either naturally moved to the middle, or from the middle: for, from the definitions, that is heavy which is moved to the middle, and that is light which is moved from the middle. But that which is moved either from or to the middle, is the same with some one of the things moved in a right line. AB, therefore, is the same with something moved in a right line, though naturally moved in a circle, which is impossible.