“There may be occasions when it is best to behave irrationally, but whether there are should be decided rationally.”
Good Thinking: The Foundations of Probability and Its Applications (University of Minnesota Press, Minneapolis, 1983), first paragraph
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I. J. Good 2
British statistician, cryptographer 1916–2009Related quotes

“The whole art of politics consists in directing rationally the irrationalities of men.”
As quoted in obituary '"Reinhold Niebuhr Is Dead; Protestant Theologian, 78" by Alden Whitman in The New York Times (2 June 1971) http://www.nytimes.com/packages/html/books/niebuhr.pdf

“The darkening of the world makes the irrationality of art rational: radically darkened art.”
Source: Aesthetic Theory

An Old Chaos: Humanism and Flying Saucers (p. 81)
The Silence of Animals: On Progress and Other Modern Myths (2013)

“The point is that humans are rarely at their best when they use rational reasoning.”
Source: Why Stock Markets Crash - Critical Events in Complex Systems (2003), Chapter 4, Positive Feedbacks, p. 106.

"Why I became a conservative," http://newcriterion.com:81/archive/21/feb03/burke.htm The New Criterion (February 2003).

Letter to The New York Times (27 February 1997)
Context: Whatever their limitations, Freud and Marx developed complex and subtle theories of human nature grounded in their observation of individual and social behavior. The crackpot rationalism of free-market economics merely relies on an abstract model of how people "must" behave.
page 148
Exiting Nirvana: A Daughter's Life In Autism (2001)