Bertrand Russell
"If a man is offered a fact which goes against his instincts, he will scrutinize it closely, and unless the evidence is overwhelming, he will refuse to believe it. If, on the other hand, he is offered something which affords a reason for acting in accordance to his instincts, he will accept it even on the slightest evidence. The origin of myths is explained in this way."
"A stupid man's report of what a clever man says can never be accurate, because he unconsciously translates what he hears into something he can understand."
"Do not fear to be eccentric in opinion, for every opinion now accepted was once eccentric."
"I would never die for my beliefs because I might be wrong."
"I think we ought always to entertain our opinions with some measure of doubt. I shouldn't wish people dogmatically to believe any philosophy, not even mine."
"In all affairs it's a healthy thing now and then to hang a question mark on the things you have long taken for granted."
"It has been said that man is a rational animal. All my life I have been searching for evidence which could support this."
"Many people would sooner die than think; In fact, they do so."
"Men fear thought as they fear nothing else on Earth -- more than ruin -- more even than death... Thought is subversive and revolutionary, destructive and terrible, thought is merciless to privilege, established institutions, and comfortable habit. Thought looks into the pit of hell and is not afraid. Thought is great and swift and free, the light of the world, and the chief glory of man."
"No one gossips about other people's secret virtues."
"Our great democracies still tend to think that a stupid man is more likely to be honest than a clever man."
"Patriots always talk of dying for their country but never of killing for their country."
"Science may set limits to knowledge, but should not set limits to imagination."
"The time you enjoy wasting is not wasted time."
"The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts."
"There are two motives for reading a book: one, that you enjoy it; the other, that you can boast about it."
"Too little liberty brings stagnation and too much brings chaos."
"War does not determine who is right - only who is left."
"Not to be absolutely certain is, I think, one of the essential things in rationality."
"When one admits that nothing is certain one must, I think, also admit that some things are much more nearly certain than others. It is much more nearly certain that we are assembled here tonight than it is that this or that political party is in the right. Certainly there are degrees of certainty, and one should be very careful to emphasize that fact, because otherwise one is landed in an utter skepticism, and complete skepticism would, of course, be totally barren and completely useless."
"Men who are unhappy, like men who sleep badly, are always proud of the fact."
"A sense of duty is useful in work, but offensive in personal relations. People wish to be liked, not be endured with patient resignation."
"One of the symptoms of an approaching nervous breakdown is the belief that one's work is terribly important."
"One should as a rule respect public opinion in so far as is necessary to avoid starvation and to keep out of prison, but anything that goes beyond this is voluntary submission to an unnecessary tyranny, and is likely to interfere with happiness in all kinds of ways."
"To fear love is to fear life, and those who fear life are already three parts dead."
"The fact that an opinion has been widely held is no evidence whatever that it is not utterly absurd; indeed in view of the silliness of the majority of mankind, a widespread belief is more likely to be foolish than sensible."
"We have, in fact, two kinds of morality side by side: one which we preach but do not practice, and another which we practice but seldom preach."
"It is undesirable to believe a proposition when there is no ground whatsoever for supposing it is true."
Socrates
"We are what we repeatedly do. Excellence, then, is a habit."
"By all means marry; if you get a good wife, you'll be happy. If you get a bad one, you'll become a philosopher."
"Death may be the greatest of all human blessings."
"Get not your friends by bare compliments, but by giving them sensible tokens of your love."
"Remember that there is nothing stable in human affairs; therefore avoid undue elation in prosperity, or undue depression in adversity."
"The only good is knowledge and the only evil is ignorance."
"Think not those faithful who praise all thy words and actions; but those who kindly reprove thy faults."
"The unexamined life is not worth living."