I realized that a methane-oxygen rocket engine could achieve a specific impulse greater than 380.

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.

Starting and growing a business is as much about the innovation, drive and determination of the people who do it as it is about the product they sell.

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.

When we got Tesla going at the very beginning, if you asked me what I thought the odds of success were, I would have said less than 50%. I would have said that failure is the most likely outcome.

Focus on something that has high value to someone else, be really rigorous in making that assessment, because natural human tendency is wishful thinking, so the challenge to entrepreneurs is telling what's the difference between really believing in your ideals and sticking to them as opposed to pursuing some unrealistic dream that doesn't actually have merit, be very rigorous in your self analysis, certainly being extremely tenacious, and just work like hell. Put in 80-100 hours every week. All these things improves the odds of success

We have a strict 'no a-hole policy' at SpaceX. And we fire people they are. I mean, we give them a little bit of warning. But if they continue to be an a-hole, then they're fired.