“… we scientists are used to this, and we take it for granted that it is perfectly consistent to be unsure, that it is possible to live and not know.”

:Richard Feynman in The Value of Science in What Do You Care What Other People Think?

“For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled.”

:Richard Feynman in Appendix F in What Do You Care What Other People Think?

“When playing Russian roulette, the fact that the first shot got off safely is of little comfort for the next.”

:Richard Feynman in Appendix F in What Do You Care What Other People Think?

“My Father had the spirit and integrity of a scientist, but he was a salesman. I remember asking him the question “How can a man of integrity be a salesman?””

:Richard Feynman in Afterthoughts in What Do You Care What Other People Think?

“If a Martian (who we’ll imagine never dies except by accident) came to Earth and saw this peculiar race of creatures – these human who live about seventy to eighty years, knowing that death is going to come – it would look to him like a terrible problem of psychology to live under those circumstances, knowing that life is only temporary. Well, we humans some how figure out how to live despite this problem: we laugh, we joke, we live.”

:Richard Feynman in What Do You Care What Other People Think? in the book titled What Do You Care What Other People Think?