We enter the world alone, we leave the world alone.

Science rests on reason and experiment, and can meet an opponent with calmness; but a belief is always sensitive.

A person possessed with an idea cannot be reasoned with.

Age does not make us childish, as some say; it finds us true children.

As we advance in life, we learn the limits of our abilities.

Experience teaches slowly, and at the cost of mistakes.

Fear is the parent of cruelty.

Human improvement is from within outward.

In everyday things the law of sacrifice takes the form of positive duty.

Instruction does not prevent wasted time or mistakes; and mistakes themselves are often the best teachers of all.

No person is ever good for much, that hasn't been swept off their feet by enthusiasm between ages twenty and thirty.

Philosophy goes no further than probabilities, and in every assertion keeps a doubt in reserve.

To deny the freedom of the will is to make morality impossible.

Superior strength is found in the long run to lie with those who had right on their side.

The secret of a person's nature lies in their religion and what they really believes about the world and their place in it.