Best of Rationality Quotes

Today, safe flight inside clouds is possible using gyroscopic instruments that report the airplane’s orientation without being misled by centrifugal effects. But the pilot’s spatial intuition is still active, and often contradicts the instruments. Pilots are explicitly, emphatically trained to trust the instruments and ignore intuition—precisely the opposite of the Star Wars advice—and those who fail to do so often perish.

-- Gary Drescher "Good and Real"

(I really like this quote as a counterweight to the ubiquitous cliche-advise to follow you intuition. Often, your intuition may be fooled. And, it cannot be repeated often enough, Good and Real is a must-read for LW-minded folks)

The white line down the center of the road is a mediator, and very likely it can err substantially towards one side the other before the disadvantaged side finds advantage in denying its authority.

Source:

-- Schelling, Strategy of conflict, p144

[The book was mentioned a couple of times here on LW, and is a nice introduction to the use of game theory in geopolitics]

Men ought to know that from nothing else but the brain comes joy, delights, laughter, and sports, and sorrows, griefs, despondency, and lamentations. And by this, in an especial manner, we acquire wisdom and knowledge, and see and hear and know what are foul and what are fair, what are bad and what are good, what are sweet, and what are unsavory. ... And by the same organ we become mad and delirious, and fears and terrors assail us. ... All these things we endure from the brain. ...In these ways I am of the opinion that the brain exercises the greatest power in the man.

-- Hippocrates, On the sacred disease (ca. 4th century BCE).

[ In this and other of his writings, Hippocrates shows such an incredible early sense for rationality and against superstition that was only rarely seen in the next 2000 after that -- and in addition, he was not just a armchair philosopher, he actually put these things is practice. So, hats off for Hippocrates, even when his medicine was not without faults of course...]

There is no opinion so absurd that some philosopher will not express it.

-- Marcus Tullius Cicero

[ while in general I value philosophy, there is also much nonsense and, especially, little progress ]

Their judgment was based more upon blind wishing than upon any sound prevision; for it is a habit of mankind to entrust to careless hope what they long for, and to use sovereign reason to thrust aside what they do not fancy.

-- Thucydides, Greek Historian, ca. 5th century BCE (Book IV, 108)

I like Thucydides for the way he tries to explain history in terms of real-politik, people, their drives and especially without including the gods in an explanation, somewhat similar to Hippocrates.

Interestingly, a modern version of this appeared in Neal Stephenson's Anathem:

Never believe a thing simply because you want it to be true

where it's called Diax's Rake.

Anathem is a great book, I'd like to add, and quite well aligned with many of the LW themes.

"It only stands to reason that where there's sacrifice, there's someone collecting the sacrificial offerings. Where there's service, there is someone being served. The man who speaks to you of sacrifice is speaking of slaves and masters, and intends to be the master."

~ Ayn Rand, Atlas Shrugged

[ I'm actually not too fond of objectivism, but this quote is spot-on ]

Extraordinary claims require extraordinary evidence -- Carl Sagan

(I know this quote is very much a cliche -- but, as a realized a long time after seeing it, it is not only a nice heuristic, but it also emphasizes the bayesian, probabilistic view of knowledge over the popperian one.)