And whenever anyone speaks without bitterness, or rather quite innocently, of man as a belly with two requirements, and a head with one; whenever any one sees, seeks, and to see only hunger, sexual instinct, and vanity as the real and only motives of human actions; in short, when any one speaks badly and not even ill of man, then ought the lover of knowledge to hearken attentively and diligently; he ought, in general, to have an open ear wherever there is talk without indignation.