Philip Stanhope, 4th Earl of Chesterfield Quote

Good manners, to those one does not love, are no more a breach of truth, than "your humble servant," at the bottom of a challengeis; they are universally agreed upon, and understand to be things of course. They are necessary guards of the decency and peace of society.

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