If I didn't exist, I would have invented myself.

A man who grows that much hair,' critics were fond of saying, 'must have a lot to hide.

1. When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong. 2. The only way of discovering the limits of the possible is to venture a little way past them into the impossible. 3. Any sufficiently advanced technology is indistinguishable from magic.

Finally, I would like to assure my many Buddhist, Christian, Hindu, Jewish, and Muslim friends that I am sincerely happy that the religion which Chance has given you has contributed to your peace of mind (and often, as Western medical science now reluctantly admits, to your physical well-being). Perhaps it is better to be un-sane and happy, than sane and un-happy. But it is the best of all to be sane and happy. Whether our descendants can achieve that goal will be the greatest challenge of the future. Indeed, it may well decide whether we have any future.

Only small minds are impressed by large numbers.

I don't pretend we have all the answers. But the questions are certainly worth thinking about.

The universe must be full of voices, calling from star to star in a myriad tongues. One day we shall join that cosmic conversation.