We are...capable of using our compassion and our intelligence, our technology and our wealth, to make an abundant and meaningful life for every inhabitant of this planet. To enhance enormously our understanding of the Universe, and to carry us to the stars.

[One's] inability to invalidate your hypothesis is not at all the same thing as proving it true.

I think the health of our civilization, the depth of our awareness about the underpinnings of our culture, and our concern for the future, can all be tested by how well we support our libraries.

Many religions have attempted to make statues of their gods very large, and the idea, I suppose, is to make us feel small. But if that's their purpose, they can keep their paltry icons. We need only look up if we wish to feel small.

In science it often happens that scientists say, "You know that's a really good argument; my position is mistaken..."

I find science so much more fascinating than science fiction. It also has the advantage of being true.

Man is a transitional animal. He is not the climax of creation