The foundation of morality is to have done, once and for all, with lying.

I am too much of a sceptic to deny the possibility of anything...

There is far too much of the feeding-bottle in education and young people ought to be supplied with good intellectual food and then left to help themselves.

It is because the body is a machine that education is possible. Education is the formation of habits, a superinducing of an artificial organization upon the natural organization of the body.

Friendship involves many things but, above all the power of going outside oneself and appreciating what is noble and loving in another.

And when you cannot prove that people are wrong, but only that they are absurd, the best course is to let them alone.

. . . I fail to find a trace [in Protestantism] of any desire to set reason free. The most that can be discovered is a proposal to change masters. From being a slave of the papacy, the intellect was to become the serf of the Bible.