Go and try to start your own government in the United States today and you'll be squashed very quickly.

Back in 2007, I had the opportunity to meet Professor Stephen Hawking through the X PRIZE Foundation. In my first conversation with him I learned that he was passionate about flying into space someday.

You've got to choose your horse ahead of time. So, if you're interested in water technology, energy technology, you get to choose between the three or four companies that you have insight into. And you have to make a bet on them before they prove anything out.

My father, who grew up picking olives on the Greek island of Lesbos, was a doctor. So my family expected me to become a physician.

The folks who go after grand challenges are impatient. They're pissed off. They're sick and tired, but in a passionate way. They're driven by a fire in their bellies to make a difference.

The best way to become a billionaire is to help a billion people.

If you give people unlimited time and money, they'll do things the same old way. But if they have to achieve the goal in a brief time, they'll either give up or try something new.