Man is not logical and his intellectual history is a record of mental reserves and compromises. He hangs on to what he can in his old beliefs even when he is compelled to surrender their logical basis.
For the past 33 years， I have looked in the mirror every morning and asked myself: 'If today were the last day of my life， would I want to do what I am 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.
