"I accidentally changed my mind."

my four-year-old

A certain mother habitually rewards her small son with ice cream after he eats his spinach. What additional information would you need to be able to predict whether the child will: a. Come to love or hate spinach, b. Love or hate ice cream, or c. Love or hate Mother?

-- Gregory Bateson, "Steps to an Ecology of Mind"

I know that most men — not only those considered clever, but even those who are very clever and capable of understanding most difficult scientific, mathematical, or philosophic, problems — can seldom discern even the simplest and most obvious truth if it be such as obliges them to admit the falsity of conclusions they have formed, perhaps with much difficulty — conclusions of which they are proud, which they have taught to others, and on which they have built their lives.

— Leo Tolstoy, 1896 (excerpt from "What Is Art?")

There is no such thing as absolute certainty, but there is assurance sufficient for the purposes of human life.

John Stuart Mill, On Liberty

He seems to have understood that 0 and 1 are not probabilities.

"It's wonderful how much we suck compared to us ten years from now!"

-- Michael Blume

Were it possible to trace the succession of ideas in the mind of Sir Isaac Newton, during the time that he made his greatest discoveries, I make no doubt but our amazement at the extent of his genius would a little subside. But if, when a man publishes his discoveries, he either through a design, or through habit, omit the intermediary steps by which he himself arrived at them, it is no wonder that his speculations confound them, and that the generality of mankind stand amazed at his reach of thought. If a man ascend to the top of a building by the help of a common ladder, but cut away most of the steps after he has done with them, leaving only every ninth of tenth step, the view of the ladder, in the condition which he has pleased to exhibit it, gives us a prodigious, but unjust view of the man who could have made use of it. But if he had intended that any body should follow him, he should have left the ladder as he constructed it, or perhaps as he found it, for it might have been a mere accident that threw it in his way... I think that the interests of science have suffered by the excessive admiration and wonder with which several first rate philosophers are considered, and that

I imagine that if my friend finally came to the conclusion that he were a machine, he would be infinitely crestfallen. I think he would think: "My God! How Horrible! I am only a machine!" But if I should find out I were a machine, my attitude would be totally different. I would say: "How amazing! I never before realized that machines could be so marvelous!"

(Raymond Smullyan)

I have found it in an OB comment by Zubon, but it was never posted as a rationality quote.

It's no wonder that truth is stranger than fiction. Fiction has to make sense.

Another Twain quote.

Conscious thought leads people to put disproportionate weight on attributes that are accessible, plausible and easy to verbalize, and therefore too little weight on other attributes. -- Ap Dijksterhuis

all arguments online seem to follow that format. It's like a giant straw man ate a radioactive non sequitor and began rampaging through downtown Tokyo.

-- jman3030

Reason is the press secretary of the emotions, the ex post facto spin doctor of beliefs we've arrived at through a largely intuitive process.

"Sanity is conforming your thoughts to reality. Conforming reality to your thoughts is creativity."

-- Unknown

Do not go gentle into that good night,
Old age should burn and rage at close of day;
Rage, rage against the dying of the light.

Though wise men at their end know dark is right,
Because their words had forked no lightning they
Do not go gentle into that good night.

Good men, the last wave by, crying how bright
Their frail deeds might have danced in a green bay,
Rage, rage against the dying of the light.

Wild men who caught and sang the sun in flight,
And learn, too late, they grieved it on its way,
Do not go gentle into that good night.

Grave men, near death, who see with blinding sight
Blind eyes could blaze like meteors and be gay,
Rage, rage against the dying of the light.

And you, my father, there on the sad height,
Curse, bless me now with your fierce tears, I pray.
Do not go gentle into that good night.
Rage, rage against the dying of the light.

-- Dylan Thomas

Not strictly a rationality quote, but screw it, it's beautiful anyway:

I take it as a given that, during the course of my lifespan, there's always been television (not color to start with, but there was TV), that indoor plumbing and lights have always been around, flight is not only possible but commonplace and pretty much always has been, and the moon landing happened before I was born.

A part of me regrets missing the introduction of all of those exciting technologies and innovations, because to me they are all background things that just are. They aren't wondrous, they just are.

No matter where you live in history, there are always improvements that you'll appreciate, but there's always amazing stuff that was there before that you will only see as part of the world as it's always been, and will be even more amazing stuff that will come after you that would probably blow your mind if you ever had the chance to see it (or would be so far beyond your comprehension you couldn't appreciate it).

You don't truly appreciate the amazing parts of an advance unless you've watched those parts happen.

To me, computers (and video games, etc), color/stereo televisions, microwaves, mobile phones,

"You rationalize, Keeton. You defend. You reject unpalatable truths, and if you can't reject them outright you trivialize them. Incremental evidence is never enough for you. You hear rumors of Holocaust; you dismiss them. You see evidence of genocide; you insist it can't be so bad. Temperatures rise, glaciers melt—species die—and you blame sunspots and volcanoes. Everyone is like this, but you most of all. You and your Chinese Room. You turn incomprehension into mathematics, you reject the truth without even knowing what it is."

--Jukka Sarasti, rationalist vampire in Peter Watts's Blindsight. Great book on neuroscience and map != territory.

Nothing exists except atoms and empty space; everything else is opinion.

-- Democritus

Everyone who takes basic statistics has it drilled into them that "correlation is not causation." (When I took psych. 1, the professor said he hoped that, if he were to come to us on our death-beds and prompt us with "Correlation is," we would all respond "not causation.") This is a problem, because one can infer correlation from data, and would like to be able to make inferences about causation. There are typically two ways out of this. One is to perform an experiment, preferably a randomized double-blind experiment, to elim

Do not ask whether a statement is true until you know what it means.

— Errett Bishop

Using language that is appropriate in one linguistic framework in a different linguistic framework is what causes philosophical confusion and pseudo puzzles, also known as the history of philosophy.

-- Thomas Cathcart & Daniel Klein, Plato and a Platypus Walk into a Bar... : Understanding Philosophy Through Jokes

"We live on an island surrounded by a sea of ignorance. As our island of knowledge grows, so does the shore of our ignorance" - John Archibald Wheeler

There is no mutually exclusive distinction between "is" and "ought". There is only a distinction between "is" and "is not". If "ought" cannot find a home in what "is", then "ought" is something that "is not".

-- Alonzo Fyfe

Sufferers must be sustained by a hope so strong that no conflict with reality can smash it - so strong, indeed, that no fulfilment could ever satisfy it...

-Nietzche

The universe will expand, then it will collapse back on itself, then will expand again. It will repeat this process forever. What you don't you know is that when the universe expands again, everything will be as it is now. Whatever mistakes you make this time around, you will live through on your next pass. Every mistake you make, you will live through again, & again, forever. So my advice to you is to get it right this time around. Because this time is all you have.

-KPAX

(I do not present this as an endorsement of the Big Bounce hypothesis.)