“When a coin is tossed, it does not necessarily fall heads or tails; it can roll away or stand on its edge.”
Source: An Introduction To Probability Theory And Its Applications (Third Edition), Chapter I, The Sample Space, p. 7
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William Feller 30
Croatian-American mathematician 1906–1970Related quotes

“Good and evil are one. Just like a coin, the head and the tail.”

Source: 2000s, The Age of Turbulence (2008), Chapter Twenty-Five, "The Delphic Future", p. 465.
“When you stand at the edge of the cliff, jump to fly, not to fall. ”
Part One, Entropy, Toy Room, p. 46
Fortune's Formula (2005)

“When danger reared its ugly head,
He bravely turned his tail and fled.”
Source: Monty Python and the Holy Grail (Book): Mønti Pythøn Ik Den Hølie Gräilen