"You know, I'm not a fan of subsidies generally. I think the right answer is to have a carbon tax."

"I'm not a fan of people who are not resilient. I think it's important to be resilient and bounce back from setbacks."

"If I can convince enough people that Mars is a good idea, then it will happen."

"The problem with humanity is that it's just so damn hard to get rid of."

"I always invest my own money in the companies I create. I don't believe in using other people's money."