"Racism, pollution and the rest of it are themselves very close to extinction."

"Nature is trying very hard to make us succeed, but nature does not depend on us. We are not the only experiment."

"Humanity is acquiring all the right technology for all the wrong reasons."

"When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong."

"Either war is obsolete or men are."

"Humanity is acquiring all the right technology for all the wrong reasons."

"Three people can keep a secret so long as two of them are dead."

"The power of speech is not in words, but in the oration."

"Stranger, if you passing meet me and desire to speak to me, why should you not speak to me? And why should I not speak to you?"

"Children are guilty of unpardonable rudeness when they spit in the face of a companion; neither are they excusable who spit from windows or on walls or furniture."

"There is this difference between happiness and wisdom, that he that thinks himself the happiest man, really is so; but he who thinks himself the wisest, is generally the greatest fool."

"A man should never put on his best trousers when he goes out to battle for freedom and truth."