Mars is the only place in the solar system where it's possible for life to become multi-planetarian.

Biofuels such as ethanol require enormous amounts of cropland and end up displacing either food crops or natural wilderness, neither of which is good.

I want to make rockets 100 times, if not 1,000 times better. The ultimate objective is to make humanity a multiplanet species. Thirty years from now, there'll be a base on the moon and on Mars, and people will be going back and forth on SpaceX rockets.

It is despairing to consider that the cost and reliability of access to space have barely changed since the Apollo era over three decades ago. Yet in virtually every other field of technology, we have made great strides in reducing cost and increasing capability.

I think it's very important to have a feedback loop, where you're constantly thinking about what you've done and how you could be doing it better.

There are really two things that have to occur in order for a new technology to be affordable to the mass market. One is you need economies of scale. The other is you need to iterate on the design. You need to go through a few versions.

I think that's the single best piece of advice: constantly think about how you could be doing things better and questioning yourself.