The biologists have essentially been pushed aside. Al Gore's just an opportunist. The person who is really responsible for this overestimate of global warming is Jim Hansen. He consistently exaggerates all the dangers.

Lucky individuals in each generation find technology appropriate to their needs.

There are three reasons, . . . apart from scientific considerations, mankind needs to travel in space. The first . . . is garbage disposal; we need to transfer industrial processes into space so that the earth may remain a green and pleasant place for our grandchildren to live in. The second . . . to escape material impoverishment: the resources of this planet are finite, and we shall not forego forever the abundance of solar energy and minerals and living space that are spread out all around us. The third . . . our spiritual need for an open frontier.

Almost everything about the universe is astounding.

If we want to go to space with humans, that's for fun not for science. Human adventures in space are just sporting events.

Boiled down to one sentence, my message is the unboundedness of life and the unboundedness of human destiny.

Mathematics is really an art, not a science.