It is no more conceivable again that the infinite should exist as a whole of similar parts. For in the first place there is no other (straight) movement beyond those mentioned: we must therefore give it one of them. And if so we shall have to admit either infinite weight or infinite lightness. Nor secondly could the body whose movement is circular be infinite since it is impossible for the infinite to move in a circle. This indeed would be as good as saying that the heavens are infinite which we have shown to be impossible.