“Existence proofs always trump theory. That’s engineering.”
Source: Short fiction, The Man Who Sold The Moon (2014), p. 135
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Cory Doctorow 53
Canadian-British blogger, journalist, and science fiction a… 1971Related quotes

“The proof of a theory is in its reasoning, not in its sponsorship”
Theory of Money and Credit http://www.econlib.org/library/Mises/msT1.html (1912)
Source: http://www.econlib.org/library/Mises/msT2.html#I.5.12 | Theory of Money and Credit

Grady Booch, Robert A. Maksimchuk, Michael W. Engle (2007) Object-Oriented Analysis and Design with Applications Chapter 6.

"On one class of functional equations" (1936), as cited in: O'Connor, John J.; Robertson, Edmund F., " Leonid Kantorovich http://www-history.mcs.st-andrews.ac.uk/Biographies/Kantorovich.html", MacTutor History of Mathematics archive, University of St Andrews

Source: 1860s, Evidence as to Man's Place in Nature (1863), Ch.2, p. 128

2010s, 2016, Donald Trump and the fitness threshold (2016)
Context: Donald Trump, the man who defied every political rule and prevailed to win his party’s nomination, last week took on perhaps the most sacred political rule of all: Never attack a Gold Star family. Not just because it alienates a vital constituency but because it reveals a shocking absence of elementary decency and of natural empathy for the most profound of human sorrows — parental grief.
Why did Trump do it? It wasn’t a mistake. It was a revelation. It’s that he can’t help himself. His governing rule in life is to strike back when attacked, disrespected or even slighted. To understand Trump, you have to grasp the General Theory: He judges every action, every pronouncement, every person by a single criterion — whether or not it/he is “nice” to Trump.

Session 410, Page 284
The Early Sessions: Sessions 1-42, 1997, The Early Sessions: Book 8

“You have no proof of this,” I said.
“No. But a theory must be tested to be disproved, Mr Bastable.”
Book 1, Chapter 8 “A Decision in Cold Blood” (p. 233)
Oswald Bastable, The Land Leviathan (1974)

“Futility is the defining characteristic of life. Pain is proof of existence”
Thomas Covenant