“There are some people who can receive a truth by no other way than to have their understanding shocked and insulted.”

Source: Galileo's Dream (2009), Ch. 15, p. 354; note: though this statement is incorporated into the story as one Galileo spoke, it is actually a quotation of one he historically made in his Dialogue Concerning The Two Chief World Systems http://www4.ncsu.edu/~kimler/hi322/Dialogue-extracts.html as translated by Stillman Drake.

Promoting "Crocker's Rules" at SL4 (c. 2000) http://www.sl4.org/crocker.html
Context: Declaring yourself to be operating by "Crocker's Rules" means that other people are allowed to optimize their messages for information, not for being nice to you. Crocker's Rules means that you have accepted full responsibility for the operation of your own mind — if you're offended, it's your fault. Anyone is allowed to call you a moron and claim to be doing you a favor. (Which, in point of fact, they would be. One of the big problems with this culture is that everyone's afraid to tell you you're wrong, or they think they have to dance around it.) Two people using Crocker's Rules should be able to communicate all relevant information in the minimum amount of time, without paraphrasing or social formatting. Obviously, don't declare yourself to be operating by Crocker's Rules unless you have that kind of mental discipline.
Note that Crocker's Rules does not mean you can insult people; it means that other people don't have to worry about whether they are insulting you. Crocker's Rules are a discipline, not a privilege. Furthermore, taking advantage of Crocker's Rules does not imply reciprocity. How could it? Crocker's Rules are something you do for yourself, to maximize information received — not something you grit your teeth over and do as a favor.

Nobel Prize Speech (1954)
Context: No writer who knows the great writers who did not receive the Prize can accept it other than with humility. There is no need to list these writers. Everyone here may make his own list according to his knowledge and his conscience.

Book IV, Ch. 19 : Of Enthusiasm (Chapter added in the fourth edition).
Variant paraphrase, sometimes cited as a direct quote: One unerring mark of the love of truth is not entertaining any proposition with greater assurance than the proofs it is built upon will warrant.
As paraphrased in Peter's Quotations : Ideas for our Time (1979) by Laurence J. Peter, p. 500; also in The Demon-Haunted World : Science as a Candle in the Dark (1994) by Carl Sagan, p. 64
An Essay Concerning Human Understanding (1689)
Context: He that would seriously set upon the search of truth, ought in the first place to prepare his mind with a love of it. For he that loves it not, will not take much pains to get it; nor be much concerned when he misses it. There is nobody in the commonwealth of learning who does not profess himself a lover of truth: and there is not a rational creature that would not take it amiss to be thought otherwise of. And yet, for all this, one may truly say, that there are very few lovers of truth, for truth's sake, even amongst those who persuade themselves that they are so. How a man may know whether he be so in earnest, is worth inquiry: and I think there is one unerring mark of it, viz. The not entertaining any proposition with greater assurance than the proofs it is built upon will warrant. Whoever goes beyond this measure of assent, it is plain receives not the truth in the love of it; loves not truth for truth's sake, but for some other bye-end.

Source: The Peter Principle (1969), p. 38: This phenomenon is called by Peter "percussive sublimation", or "being kicked upstairs".

Another Roadside Attraction (1971)

The View. March 5, 2012.
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