If you once forfeit the confidence of your fellow citizens, you can never regain their respect and esteem. It is true that you may fool all of the people some of the time; you can even fool some of the people all of the time; but you can't fool all of the people all of the time. -Speech at Clinton, Illinois, September 8, 1854.
I don't believe any of you have ever read Paradise Lost, and you don't want to. That's something that you just want to take on trust. It's a classic ... something that everybody wants to have read and nobody wants to read.
I have known a vast quantity of nonsense talked about bad men not looking you in the face. Don't trust that conventional idea. Dishonesty will stare honesty out of countenance any day in the week, if there is anything to be got by it.
Whoever deliberately attempts to insure confidentiality with another person is usually in doubt as to whether he inspires that person's confidence in him. One who is sure that he inspires confidence attaches little importance to confidentiality.