The First Principle Is That You Must Not Fool Yourself -- And You Are The Easiest Person To Fool.

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The first principle is that you must not fool yourself -- and you are the
easiest person to fool. So you have to be very careful about that. After
you've not fooled yourself, it's easy not to fool other scientists.
-- Richard P. Feynman (1918-1988), "Cargo Cult Science"
-- from "Surely You're Joking, Mr. Feynman" (1985)

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