The part of uranium that's fissile - when you hit it with a neutron, it splits in two - is about 0.7%. The reactors we have today are burning that 0.7%.

It’s been proven that of all the interventions to reduce poverty, improving agricultural productivity is the best.

Ridiculous sums of money can be confusing.

[Smart] is an elusive concept. There's a certain sharpness, an ability to absorb new facts. To ask an insightful question. To relate to domains that may not seem connected at first. A certain creativity that allows people to be effective.

If you say to people that there's less violence today than in the past, they would be stunned to hear that. But it's the truth, even though we have awful things happening in Syria or Sudan.

My mom was on the United Way group that decides how to allocate the money and looks at all the different charities and makes the very hard decisions about where that pool of funds is going to go.

If your goal is to make the world a better place, one thing you can do is pick a specific challenge that you really care about. Then, learn as much as you can about it and try to volunteer your time to help an organization that is working in this area. While you're doing that, look for creative new ways to use technology to tackle parts of the problem that you come in contact with.