Philip Stanhope, 4th Earl of Chesterfield Quote

Keep your own secret, and get out other people's. Keep your own temper, and artfully warm other people's. Counterwork your rivalswith diligence and dexterity, but at the same time with the utmost personal civility to them: and be firm without heat.

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