"The statement of Diogenes, that Herakleides attended the Pythagorean schools is of... importance... as it is... likely... their influence (which is also perceptible in his ideas about atoms, which he calls masses...), tended to convince him of the truth of the... simple explanation of the daily motion of the stars proposed by Hiketas and Ekphantus. ... He first alludes to Herakleides when discussing the chapter in which Aristotle considers the motion of the starry vault. Aristotle... remarks that, taking for granted that the earth is at rest, the starry sphere... and the planets might either both be at rest, or both be in motion, or one be at rest and the other in motion. And these cases he considers (says Simplicius) "on account of there being some, among whom were Herakleides of Pontus and Aristarchus, who believed they could save the phenomena (account for the observed facts) by making the heavens and the stars be immovable, but making the earth move round the poles of the equator... from the west, each day one revolution as near as possible; but 'as near as possible' is added on account of the [daily] motion of the sun of one part (degree); so that, if then the earth does not move, which presently he (Aristotle) is going to show, the hypothesis of both being at rest cannot possibly save the phenomena.""