When some people urged that it is impossible for man to live like the animals owing to the tenderness of his flesh and because he is naked and unprot… - Dio Chrysostom

Pleasure assails a man through each and every sense that he has; and while he must face and grapple with work, to pleasure he must give the widest berth possible and have none but unavoidable dealings with her. And herein the strongest man is indeed strongest, one might almost say, who can keep the farthest away from pleasures; for it is impossible to dwell with pleasure or even to dally with her for any length of time without being completely enslaved.

If in the guise of philosophers, they [declaim speeches] with a view to their own profit and reputation, and not to improve you, that indeed is shocking. For it is as if a physician when visiting patients should disregard their treatment and their restoration to health, and should bring them flowers and courtesans and perfume.

Just as the good physician should go and offer his services where the sick are most numerous, so, said [Diogenes], the man of wisdom should take up his abode where fools are thickest in order to convict them of their folly and reprove them.