What a person thinks on his own without being stimulated by the thoughts and experiences of the other people is even in the best case rather paltry and monotonous.

To the Master's honor all must turn, each in its track, without a sound, forever tracing Newton's ground.

Adversity introduces a man to himself.

The only source of knowledge is experience.

Conviction is a good motive, but a bad judge.

You cannot prevent and prepare for war at the same time.

People start their lives at last when they are able to live for something other than themselves.