I always had an existential crisis, trying to figure out ‘what does it all mean?’ I came to the conclusion that if we can advance the knowledge of the world, if we can expand the scope and scale of consciousness, then, we’re better able to ask the right questions and become more enlightened. That’s the only way to move forward.

I'm a Silicon Valley guy. I just think people from Silicon Valley can do anything.

It's just mind-blowingly awesome. I apologize, and I wish I was more articulate, but it's hard to be articulate when your mind's blown-but in a very good way.

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.

I just want to retire before I go senile because if I don't retire before I go senile, then I'll do more damage than good at that point.

If anyone thinks they'd rather be in a different part of history, they're probably not a very good student of history. Life sucked in the old days. People knew very little, and you were likely to die at a young age of some horrible disease. You'd probably have no teeth by now. It would be particularly awful if you were a woman.

I think that's an important thing to do, to really pay attention to negative feedback, and solicit it, particularly from friends. This may sound like simple advice, but hardly anyone does that, and it's incredibly helpful.