A quote
There should be a difference between the applause of the theatre and the applause of the school; and there is a certain decency even in bestowing praise. If you mark them carefully, all acts are always significant, and you can gauge character by even the most trifling signs. The lecherous man is revealed by his gait, by a movement of the hand, sometimes by a single answer, by his touching his head with a finger, by the shifting of his eye. The scamp is shown up by his laugh; the madman by his face and general appearance. These qualities become known by certain marks; but you can tell the character of every man when you see how he gives and receives praise.
Seneca·Letter 52 — On Choosing Our Teachers (§12)·trans. Gummere