itrownot
Feynmen's principle was clearly more formulated to offer some pretty good advice, it seems, than it was to delineate a scientifically rigorous statement of fact, much like a modern technical version of Shakespeare's "to thine own self be true."
Actually it is aimed precisely at scientific rigour. The quote states
"The first principle is that you must not fool yourself--and you are the easiest person to fool."
It is a single sentence derived from a talk Feynman gave entitled Cargo Cult Science. A website where it can be read in its entirety is located here
Gas Resources – gasresources.net
"A man's ethical behavior should be based effectually on sympathy, education, and social ties; no religious basis is necessary. Man would indeed be in a poor way if he had to be restrained by fear of punishment and hope of reward after death."
Albert Einstein
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