My vision is for a fully reusable rocket transport system between Earth and Mars that is able to re-fuel on Mars - this is very important - so you don't have to carry the return fuel when you go there.

Land on Mars, a round-trip ticket - half a million dollars. It can be done.

I think most of the important stuff on the Internet has been built. There will be continued innovation, for sure, but the great problems of the Internet have essentially been solved.

I don't think it's a good idea to plan to sell a company.

The revolutionary breakthrough will come with rockets that are fully and rapidly reusable. We will never conquer Mars unless we do that. It'll be too expensive. The American colonies would never have been pioneered if the ships that crossed the ocean hadn't been reusable.

You can just reload, propel it and fly again. This is extremely important for revolutionizing access to space because as long as we continue to throw away rockets and space crafts, we will never truly have access to space.

The fuel cell is just a fundamentally inferior way of delivering electrical energy to an electric motor than batteries.