Source: The Jungles of Randomness: A Mathematical Safari (1997), Chapter 10, “Lifetimes of Chance” (p. 202)
“The only thing that makes life possible is permanent, intolerable uncertainty: not knowing what comes next.”
Source: Hainish Cycle, The Left Hand of Darkness (1969), Chapter 5 “The Domestication of Hunch” (p. 70)
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Ursula K. Le Guin 292
American writer 1929–2018Related quotes

65; a slight variant of this statement was later published in Parables and Paradoxes (1946):
The expulsion from Paradise is in its main significance eternal:
Consequently the expulsion from Paradise is final, and life in this world irrevocable, but the eternal nature of the occurrence (or, temporally expressed, the eternal recapitulation of the occurrence) makes it nevertheless possible that not only could we live continuously in Paradise, but that we are continuously there in actual fact, no matter whether we know it here or not.
The Zürau Aphorisms (1917 - 1918)

Elliot's Debates, volume 2, p. 364. (28 July 1788)

Jack
Titanic (1997)
Context: I got everything I need right here with me. I got air in my lungs, a few blank sheets of paper. I mean, I love waking up in the morning not knowing what's gonna happen or, who I'm gonna meet, where I'm gonna wind up. Just the other night I was sleeping under a bridge and now here I am on the grandest ship in the world having champagne with you fine people. I figure life's a gift and I don't intend on wasting it. You don't know what hand you're gonna get dealt next. You learn to take life as it comes at you... to make each day count.

“The most precious thing in life is its uncertainty.”
Essays in Idleness (1967 Columbia University Press, Trns: Donald Keene)
Context: If man were never to fade away like the dews of Adashino never to vanish like the smoke over Toribeyama, but lingered on forever in the world, how things would lose their power to move us! The most precious thing in life is its uncertainty. Consider living creatures- none lives so long a man. The May fly waits not for the evening, the summer cicada knows neither spring nor autumn. What a wonderfully unhurried feeling it is to live even even a single year in perfect serenity.
Five Elements Five Dakinis http://www.unfetteredmind.org/five-elements-five-dakinis-9#FEFD090:33:46.8. Unfettered Mind http://www.unfetteredmind.org.. (2007-07-09) (Topic: Practice)