"The existence of the antichthon was... a hypothesis intended to account for... eclipses. ...Aristotle says that the Pythagoreans invented it... to bring the number of revolving bodies up to ten; but that is a... sally... Aristotle... knew better. In his work on the Pythagoreans... he said... eclipses of the moon were caused sometimes by.... the earth and sometimes by... the antichthon... the same statement was made by Philip of Opous..."