The universe is almost 14 billion years old, and, wow! Life had no problem starting here on Earth! I think it would be inexcusably egocentric of us to suggest that we're alone in the universe.

I think the greatest of people in society carved niches that represented the unique expression of their combinations of talents, and if everyone had the luxury of expressing the unique combinations of talents in this world, our society would be transformed overnight.

Asteroids have us in our sight. The dinosaurs didn't have a space program, so they're not here to talk about this problem. We are, and we have the power to do something about it. I don't want to be the embarrassment of the galaxy, to have had the power to deflect an asteroid, and then not, and end up going extinct.

Not enough people in this world, I think, carry a cosmic perspective with them. It could be life-changing.

We live on this speck called Earth - think about what you might do, today or tomorrow - and make the most of it.

I think the greatest of people that have ever been in society, they were never versions of someone else. They were themselves.