I think you should always bear in mind that entropy is not on your side.

Failure is an option here. If things are not failing, you are not innovating enough.

When something is important enough, you do it even if the odds are not in your favor.

People should pursue what they're passionate about. That will make them happier than pretty much anything else.

I think it is possible for ordinary people to choose to be extraordinary.

I'm extremely confident that solar will be at least a plurality of power, and most likely a majority... in less than 20 years.

Constantly seek criticism. A well thought out critique of what you're doing is as valuable as gold

Optimism, pessimism, f**k that; we're going to make it happen. As God is my bloody witness, I'm hell-bent on making it work.

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

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

My mentality is that of a samurai. I would rather commit seppuku than fail.

Be kind to your future self, and your future will be kind to you.

Quality is the best business plan.

My main nurturing instinct toward children is mild sadism--picking them up and threatening to drop them--which is why I am a good uncle but would make a poor father.

People do not lack strength they lack will.

Honestly, I didn't have the patience for biology or history in an academic sense, but I always liked the kind of big questions.

There's no greater lifestyle and no greater happiness than that of having a continual conversation with God.

We regard God as an airman regards his parachute; it's there for emergencies but he hopes he'll never have to use it.

When I was younger I used to be devastated if I would lose.

Wonder [said Socrates] is very much the affection of a philosopher; for there is no other beginning of philosophy than this.

It is a lot harder now to be a police officer than what it used to be.