Anyone who conducts an argument by appealing to authority is not using his intelligence; he is just using his memory.
— Leonardo da Vinci

The tension between "yes" and "no," between "I can" and "I cannot," makes us feel that, in so many instances, human life is an interminable debate with one's self.
Anatole Broyard debate quote

Use soft words and hard arguments.
— English Proverbs

Strong and bitter words indicate a weak cause.
— Victor Hugo

A long dispute means that both parties are wrong
— debate quotation by Voltaire