Whatever the reason you're on Mars, I'm glad you're there, and I wish I was with you.

I can find in my undergraduate classes, bright students who do not know that the stars rise and set at night, or even that the Sun is a star.

There is today-in a time when old beliefs are withering-a kind of philosophical hunger, a need to know who we are and how we got here. It is an on-going search, often unconscious, for a cosmic perspective for humanity

One trend that bothers me is the glorification of stupidity, that the media is reassuring people it's alright not to know anything. That to me is far more dangerous than a little pornography on the Internet.

Personally, I would be delighted if there were a life after death, especially if it permitted me to continue to learn about this world and others, if it gave me a chance to discover how history turns out.

Imagine a room awash in gasoline, and there are two implacable enemies in that room. One of them has nine thousand matches. The other has seven thousand matches. Each of them is concerned about who's ahead, who's stronger. Well that's the kind of situation we are actually in. The amount of weapons that are available to the United States and the Soviet Union are so bloated, so grossly in excess of what's needed to dissuade the other, that if it weren't so tragic, it would be laughable. What is necessary is to reduce the matches and to clean up the gasoline.

Think of how many religions attempt to validate themselves with prophecy. Think of how many people rely on these prophecies, however vague, however unfulfilled, to support or prop up their beliefs. Yet has there ever been a religion with the prophetic accuracy and reliability of science? ... No other human institution comes close.