Cornelius Nepos, Eumenes of Cardia 1.5-6

With us, indeed, scribes are considered hirelings, as in fact they are; in Greece, on the contrary, no one is accepted for such a position unless he is of respectable family and of proven fidelity and ability, since he is necessarily acquainted with all his superior's plans.

This position of friendship with Philip Eumenes held for seven years. When Philip was assassinated, he held the same rank with Alexander for thirteen years. During the latter part of that time he commanded one of the two corps of cavalry known as 'The Band of the Comrades.' Moreover, he was always asked for his advice by both kings and given a share in all their affairs.