“You can fool everyone else, but you can't fool your own mind.”
Source: Getting Things Done: The Art of Stress-Free Productivity
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David Allen 119
American productivity consultant and author 1945Related quotes

“Life's no piece of cake, mind you, but the recipe's my own to fool with.”
Source: Hard-Boiled Wonderland and the End of the World

“Your father is a fool skin deep; but you are a fool to your very marrow.”
Eve to Cain, in Pt. I, Act II
1920s, Back to Methuselah (1921)

Speech in http://georgewbush-whitehouse.archives.gov/news/releases/2002/09/20020917-7.html Nashville, Tennessee, (September 17, 2002), in which the president confused a centuries-old proverb ("Fool me once, shame on you; fool me twice, shame on me.")
2000s, 2002

Source: Song No Role Modelz

“Any fool can make a rule
And every fool will mind it.”
February 3, 1860
Journals (1838-1859)
Source: http://thoreau.library.ucsb.edu/writings_journals_pdfs/J15f4-f6.pdf#page=289
Source: Journal #14

“4537. The Fool is busy in everyone's Business but his own.”
Introductio ad prudentiam: Part II (1727), Gnomologia (1732)