Common sense (which, in truth, is very uncommon) is the best sense I know of: abide by it; it will counsel you best.
Lord ChesterfieldGood 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.
Lord Chesterfield