Xenophon

“ Parysatis, his mother, was his first resource; for she had more love for Cyrus than for Artaxerxes upon his throne. Moreover Cyrus's behaviour towards all who came to him from the king's court was such that, when he sent them away again, they were better friends to himself than to the king his brother. Nor did he neglect the barbarians in his own service; but trained them, at once to be capable as warriors and devoted adherents of himself. Lastly, he began collecting his Hellenic armament, but with the utmost secrecy, so that he might take the king as far as might be at unawares. ”

“ Aristippus was, as we learn from the "Meno" of Plato, a native of Larisa, of the family of the Aleuadae, and a pupil of Gorgias. He was also a lover of Menon, whom he appears to have sent on this expedition instead of himself. ”

“ In this way he secured to himself the secret maintenance of a fourth armament.
Further, he bade Proxenus, a Boeotian, who was another friend, get together as many men as possible, and join him in an expedition which he meditated against the Pisidians, [4] who were causing annoyance to his territory. Similarly two other friends, Sophaenetus the Stymphalian, [5] and Socrates the Achaean, had orders to get together as many men as possible and come to him, since he was on the point of opening a campaign, along with Milesian exiles, against Tissaphernes. ”