The Ladies' Book of Etiquette, and Manual of Politeness
Never question the veracity of any statement made in general conversation. If you are certain a statement is false, and it is injurious to another person, who may be absent, you may quietly and courteously inform the speaker that he is mistaken, but if the falsehood is of no consequence, let it pass. If a statement appears monstrous, but you do not know that it is false, listen, but do not question its veracity. It may be true, though it strikes you as improbable.
Never attempt to dispara