32 Upon some it is needful to keep a close watch, even in the minutest details, because if they think they are unperceived (as they would contrive to be), they are puffed up with the idea of their own wisdom. Of others it is better to take no notice, but seeing not to see, and hearing not to hear them, according to the proverb, that we may not drive them to despair, under the depressing influence of repeated reproofs, and at last to utter recklessness, when they have lost the sense of self-respect, the source of persuasiveness. In some cases we must even be angry, without feeling angry, or treat them with a disdain we do not feel, or manifest despair, though we do not really despair of them, according to the needs of their nature. Others again we must treat with condescension and lowliness, aiding them readily to conceive a hope of better things. Some it is often more advantageous to conquer— by others to be overcome, and to praise or deprecate, in one case wealth and power, in another poverty and failure.
Source: Orations (New Advent)