If children were brought into the world by an act of pure reason alone, would the human race continue to exist? Would not a man rather have so much sympathy with the coming generation as to spare it the burden of existence, or at any rate not take it upon himself to impose that burden upon it in cold blood?

Obstinacy is the result of the will forcing itself into the place of the intellect.

Patriotism, when it wants to make itself felt in the domain of learning, is a dirty fellow who should be thrown out of doors.

Thus, the task is not so much to see what no one yet has seen, but to think what nobody yet has thought about that which everybody sees.

Nothing in life gives a man so much courage as the attainment or renewal of the conviction that other people regard him with favor; because it means that everyone joins to give him help and protection, which is an infinitely stronger bulwark against the ills of life than anything he can do himself.

Honor has not to be won; it must only not be lost.

The fruits of Christianity were religious wars, butcheries, crusades, inquisitions, extermination of the natives of America, and the introduction of African slaves in their place.