Philip Stanhope, 4th Earl of Chesterfield Quote

If a man, notoriously and designedly, insults and affronts you, knock him down; but if he only injures you, your best revenge is to be extremely civil to him in your outward behaviour, though at the same time you counterwork him, and return him the compliment, perhaps with interest.

Letters Written by the Earl of Chesterfield to His Son (ed. 1827)