With a pen in my hand I have successfully stormed bulwarks from which others armed with sword and excommunication have been repulsed.

All mathematical laws which we find in Nature are always suspect to me, in spite of their beauty. They give me no pleasure. They are merely auxiliaries. At close range it is all not true.

If people should ever start to do only what is necessary millions would die of hunger.

The most heated defenders of a science, who cannot endure the slightest sneer at it, are commonly those who have not made very much progress in it and are secretly aware of this defect.

Many things about our bodies would not seem to us so filthy and obscene if we did not have the idea of nobility in our heads.

Some people come by the name of genius in the same way that certain insects come by the name of centipede -- not because they have a hundred feet, but because most people can't count above 14.

With most men, unbelief in one thing springs from blind belief in another.