Some people don't like change, but you need to embrace change if the alternative is disaster.

The future of humanity is going to bifurcate in two directions: Either it's going to become multiplanetary, or it's going to remain confined to one planet and eventually there's going to be an extinction event.

It was obvious to me that we could never colonize Mars without reusability, any more than America would have been colonized if they had to burn the ships after every trip.

We need to figure out how to have the things we love, and not destroy the world.

My background educationally is physics and economics, and I grew up in sort of an engineering environment - my father is an electromechanical engineer. And so there were lots of engineery things around me.

Boeing just took $20 billion and 10 years to improve the efficiency of their planes by 10 percent. That's pretty lame. I have a design in mind for a vertical liftoff supersonic jet that would be a really big improvement.

You have to be pretty driven to make it happen. Otherwise, you will just make yourself miserable.