Lucian Eunuchus 8

[8] That was what the judges dwelt upon, and the point thenceforward at issue was whether the seal of approval should be set upon a eunuch who was proposing himself for a career in philosophy and requesting that the governance of boys be committed to him. One said that presence and a fine physical endowment should be among the attributes of a philosopher, and that above all else he should have a long beard that would inspire confidence in those who visited him and sought to become his pupils, one that would befit the ten thousand drachmas which he was to receive from the Emperor, whereas a eunuch was in worse case than a cut priest, for the latter had at least known manhood once, but the former had been marred from the very first and was an ambiguous sort of creature like a crow, which cannot be reckoned either with doves or with ravens.