I cannot take back one word or action; the past does not change for anyone.

I worked hard at memorizing lists of facts and figures, and carried with me a book of facts.

Some of you read with me 40 years ago a portion of Aristotle's Ethics, a selection of passages that describe his idea of happiness. You may not remember too well.

Because the world is radically new, the ideal encyclopedia should be radical, too.

Education in the West, particularly higher education in America, has lost the ability to see the universe from very far away.

I have learned a lot about good and evil - they are not always what they appear to be.

I cannot take back one word or action; the past does not change for anyone.