Bion of Borysthenes Quote

Just as the good actor perform well whatever role the poet assigns, so too must the good man perform whatever Fortune assigns. For she, just like a poet, sometimes assigns the leading role, sometimes that of the supporting role; sometimes that of a king, sometimes that of a beggar. Do not, therefore, being a supporting actor, desire the role of the lead.

As quoted by Teles of Megara, fr. 2, On Self-Sufficiency