Diogenes Laertius Vitae philosophorum 5.1.4

[4] and married her with his consent, and in an excess of delight sacrificed to a weak woman as the Athenians did to Demeter of Eleusis ¹ ; and that he composed a paean in honour of Hermias, which is given below; next that he stayed in Macedonia at Philip’s court and received from him his son Alexander as his pupil; that he petitioned Alexander to restore his native city which had been destroyed by Philip and obtained his request; and that he also drew up a code of laws for the inhabitants. We learn further that, following the example of Xenocrates, he made it a rule in his school that every ten days a new president should be appointed. When he thought that he had stayed long enough with Alexander, he departed to Athens, having first presented to Alexander his kinsman Callisthenes of Olynthus.