Our flame is taking the normal depleted uranium - the 99.3 percent that's cheap as heck, and there's a pile of it sitting in Paducah, Kentucky that's enough to power the United States for hundreds and hundreds of years. You're taking that and you are converting it to plutonium - and then you're burning that.

We paired this announcement of the R&D [commitment] with the so-called Breakthrough Energy Coalition, which is 27 [major investors] saying, "Hey, we'll put significant money into [energy innovations] when they're ready to spin out probably into startup companies."

K to 12 is partly about babysitting the kids so the parents can do other things.

The barrier to change is not too little caring; it is too much complexity. To turn caring into action, we need to see a problem, see a solution, and see the impact. But complexity blocks all three steps.

Natural epidemics can be extremely large. Intentionally caused epidemics, bioterrorism, would be the largest of all.

You may have heard of Black Friday and Cyber Monday. There's another day you might want to know about: Giving Tuesday. The idea is pretty straightforward. On the Tuesday after Thanksgiving, shoppers take a break from their gift-buying and donate what they can to charity.

I have $100 billion... You realize I could spend $3 million a day, every day, for the next 100 years? And that's if I don't make another dime.