There is a subtle danger in a man thinking that he is "fixed" for life. It indicates that the next jolt of the wheel of progress is going to fling him off.

We know it because democracy alone has constructed an unlimited civilization capable of infinite progress in the improvement of human life.

If today were the last day of my life, Would I want to do what I'm about to do today? And whenever the answer has been "no" for too many days in a row, I know I need to change something.

True life is lived when tiny changes occur.

The more we live by our intellect, the less we understand the meaning of life.

For if we allow that human life is always guided by reason, we destroy the premise that life is possible at all.