Indeed, the dictum that truth always triumphs over persecution, is one of those pleasant falsehoods which men repeat after one another till they pass into commonplaces, but which all experience refutes.

The real advantage which truth has, consists in this, that when an opinion is true, it may be extinguished once, twice, or many times, but in the course of ages there will generally be found persons to rediscover it.

Truth gains more even by the errors of one who, with due study and preparation, thinks for himself, than by the true opinions of those who only hold them because they do not suffer themselves to think.

I doubt whether all mechanical inventions yet made have lightened the day's toil of any human being.

Almost all rich veins of original and striking speculation have been opened by systematic half-thinkers.

That so few dare to be eccentric marks the chief danger of the time.

A state which dwarfs its men, in order that they may be more docile instruments in its hands-even for beneficial purposes-will find that with small men no great thing can really be accomplished.

The peculiarity of the evidence of mathematical truths is that all the argument is on one side.