An idealist is one who, on noticing that a rose smells better than a cabbage, concludes that it will also make better soup.

-- H. L. Mencken, describing halo bias before it was named

Not everything that is more difficult is more meritorious.

-Saint Thomas Aquinas

I wish I would have memorized this quote before attending university.

*This comment was inspired by Will_Newsome's attempt to find rationality quotes in Summa Theologica.

The road to wisdom? — Well, it's plain
and simple to express:
Err
and err
and err again
but less
and less
and less.

--Piet Hein

Lesswrong!

Do not accept any of my words on faith,
Believing them just because I said them.
Be like an analyst buying gold, who cuts, burns,
And critically examines his product for authenticity.
Only accept what passes the test
By proving useful and beneficial in your life.

-- The Buddha, Jnanasara-samuccaya Sutra

“A casual stroll through the lunatic asylum shows that faith does not prove anything.”

• Friedrich Nietzsche

...when you do have a deep understanding, you have solved the problem and it is time to do something else. This makes the total time you spend in life reveling in your mastery of something quite brief. One of the main skills of research scientists of any type is knowing how to work comfortably and productively in a state of confusion.

-Anon http://www.quora.com/What-is-it-like-to-have-an-understanding-of-very-advanced-mathematics#ans873950

(emphasis mine)

"Never interrupt your enemy while he is making a mistake." -- Napoleon Bonaparte

(This has been mentioned before on LW but not in a quote thread. I figured it was fair game.)

"When picking fruit, an excellent first choice is the low-hanging ladderfruit. It is especially delicious."

--Frank Adamek

.

In questions of this appalling magnitude, I find the best way to "overcome bias" is often to find perspectives which seem to make each answer obvious. Once we recognize that both A and B are obviously true, and A is inconsistent with B, we are in the right mindset for actual thought.

--Mencius Moldbug

Human knowledge and human power meet in one; for where the cause is not known the effect cannot be produced. Nature to be commanded must be obeyed; and that which in contemplation is as the cause is in operation as the rule.

Francis Bacon

Use only that which works, and take it from any place you can find it.

--Bruce Lee

It’s not a good idea for members of the faith-based community like Hitchens to proclaim things like: Science proves we’re all genetically equal, so therefore you shouldn’t be beastly toward people of other races. The obvious flaw in this strategy is that eventually people will figure out that you are lying about what the science of genetics says, and therefore, by your own logic, that discredits the perfectly valid second half of your assertion.

--Steve Sailer

In short, they made unrealistic demands on reality and reality did not oblige them.

Cory Doctorow talking about DRM, but I think there are some wider applications.

Most people are theists not because they were "reasoned into" believing in God, but because they applied Occam's razor at too early an age. Their simplest explanation for the reason that their parents, not to mention everyone else in the world, believed in God, was that God actually existed. The same could be said for, say, Australia.

--Mencius Moldbug

"The last enemy that shall be destroyed is death"

--1 Corinthians 15:26

(I wonder what Eliezer would've made of it - as far as I know, he never read Deathly Hallows and so never read about the tombstone.)

“The general method that Wittgenstein does suggest is that of ’shewing that a man has supplied no meaning for certain signs in his sentences’.

I can illustrate the method from Wittgenstein’s later way of discussing problems. He once greeted me with the question: ‘Why do people say that it was natural to think that the sun went round the earth rather than that the earth turned on its axis? I replied: ‘I suppose, because it looked as if the sun went round the earth.’ ‘Well,’ he asked, ‘what would it have looked like if it had looked as if the earth turned on its axis?’

This question brought it out that I had hitherto given no relevant meaning to ‘it looks as if’ in ‘it looks as if the sun goes round the earth’.

My reply was to hold out my hands with the palms upward, and raise them from my knees in a circular sweep, at the same time leaning backwards and assuming a dizzy expression. ‘Exactly!’ he said.”

–Elizabeth Anscombe, [An Introduction To Wittgenstein’s Tractatus](http://www.archive.org/details/introductiontowi009827mbp) (1959); apropos of a recent Scot Sumner blog post

Science isn't just a job, it's a means of determining truth. Methods of determining truth that aren't trustworthy in the laboratory don't become trustworthy when you leave it. There is no doctrine of applying scientific methodology to every aspect of one's life, you either follow trustworthy methods of investigation or you don't, and "follow trustworthy methods of investigation" is the core of science.

~Desertopa, TVTropes Forum

The ultimate theological question is: ‘Where does the Sun go at night?’.

The answer that so many civilisations agreed for so long was: ‘The Sun is driven by one of the gods, and at night it goes under the Earth to fight a battle. There is at least some risk that the god will lose this battle, and so the Sun may not rise tomorrow’. It’s something the human race understood was a cast iron fact before they knew how to cast iron. It survived as the working model twenty-five times longer than the four hundred years we’ve understood the Earth goes around the Sun.

Lance Parkin, Above us only sky

This is less a rationality quote than a "yay science" quote, but I find that impressive beyond words. For millenia that was a huge and frightening question, and then we went and answered it, and now it's too trivial to point out. We found out where the sun goes at night. I want to carve a primer on cosmology in gold letters on a mountain, entitled something in all caps along the lines of "HERE IS THE GLORY OF HUMANKIND".

The truth is common property. You can't distinguish your group by doing things that are rational, and believing things that are true.

Paul Graham, Lies We Tell Kids

If some persons died, and others did not die, death would indeed be a terrible affliction.

--Jean de la Bruyère

Prompted by Maniakes', but sufficiently different to post separately:

It cannot have escaped philosophers' attention that our fellow academics in other fields--especially in the sciences--often have difficulty suppressing their incredulous amusement when such topics as Twin Earth, Swampman, and Blockheads are posed for apparently serious consideration. Are the scientists just being philistines, betraying their tin ears for the subtleties of philosophical investigation, or have the philosophers who indulge in these exercises lost their grip on reality?

These bizarre examples all attempt to prove one "conceptual" point or another by deliberately reducing something underappreciated to zero, so that What Really Counts can shine through. Blockheads hold peripheral behavior constant and reduce internal structural details (and--what comes to the same thing--intervening internal processes) close to zero, and provoke the intuition that then there would be no mind there; internal structure Really Counts. Manthra is more or less the mirror-image; it keeps internal processes constant and reduces control of peripheral behavior to zero, showing, presumably, that external behavior Reall

As in the Roman empire age, the theoretical concepts, taken out of the theories assigning their meaning and considered instead real objects, whose existence can be apparent only to the initiated people, are used to amaze the public. In physics courses the student (now unaware of the experimental basis of heliocentrism or of atomic theory, accepted on the sole basis of the authority principle) gets addicted to a complex and mysterious mythology, with orbitals undergoing hybridization, elusive quarks, voracious and disquieting black holes and a creating Big Bang: objects introduced, all of them, in theories totally unknown to him and having no understandable relation with any phenomenon he may have access to.

Lucio Russo, The Forgotten Revolution: How Science Was Born in 300 BC and Why it Had to Be Reborn

As an experimental psychologist I have been trained not to believe anything unless it can be demonstrated in the laboratory on rats or sophomores.

Steven Pinker, Words and Rules

We made our oath to Vavilov
We'd not betray the solanum
The acres of asteraceae
To our own pangs of starvation

"When The War Came", by The Decemberists

(from memory, will fix any errors later)

I replied as follows: "What would you think of someone who said, "I would like to have a cat, provided it barked"? [...] As a natural scientist, you recognize that you cannot assign characteristics at will to chemical and biological entities, cannot demand that cats bark or water burn. Why do you suppose that the situation is different in the "social sciences?"

-- Milton Friedman