"When people agree with me I always feel that I must be in the wrong."Here are some others for fun:
"Every great man has his disciples, and it is always Judas who writes the biography."These are also amusing because they reverse common sense:
"I can resist everything but temptation."
"Falsehoods [are] the truth of other people."
"The only duty we owe to History is to rewrite it."
"A thing is not necessarily true because a man dies for it."
"Life is far too important a thing ever to talk seriously about."Being a historian, the second to last saying here particularly speaks to me!
"Moderation is a fatal thing. Nothing succeeds like excess."
"Anyone can make history. Only a great man can write it."
"The English have everything in common with America nowadays except, of course, language."