The world owes all its onward impulses to men ill at ease. The happy man inevitably confines himself within ancient limits.

The true essence of scientific discovery is not in the answers it provides, but in the new questions it raises.

It’s not the world that’s cruel. It’s the people in it.

When you say 'yes' to others, make sure you are not saying 'no' to yourself.

不为自己思考的人根本不会思考。