[redschell]

Hey, did he take that from Richard Feynman, or was Feynman first with the quote: "The first principle is that you must not fool yourself and you are the easiest person to fool."

[mhartl]

It's a quote from "Cargo Cult Science" (p. 313 of Surely You're Joking, Mr. Feynman!):

The first principle is that you must not fool yourself—and you are the easiest person to fool. —Richard Feynman

[rokhayakebe]

Curious. Did you remember the page of the top or did you look it up?

[mhartl]

I have every page of Surely You're Joking memorized.

Bazinga.

[rokhayakebe]

I am adding you to my list of heroes.

[csallen]

It's very possible (likely) that it originally came from Feynman. Munger quotes him often.

[gwern]

Given the relative timelines, and my own citation in my quote collection to Feynman, I'm happy assigning a very high probability to it being Feynman.