Having kids has been a fantastic thing for me. It's meant that I'm a little more balanced. In my twenties I worked massively, hardly took vacation at all. Now, I, with the help of my wife, I'm always making sure I've got a good balance of how I spend my time.

The Gates Foundation has learned that two questions can predict how much kids learn: 'Does your teacher use class time well?' and, 'When you're confused, does your teacher help you get straightened out?'

We believe the world changes when the boldest thinking is directed at the toughest problems

So on the demand side [for energy], there have been a variety of policies that globally have been way over $50 billion a year of tax credits, raising the price of electricity through things like renewable portfolio standards, so the total amount of money that's gone into sending a price signal to push up demand versus what would happen without it has been gigantic.

A fundamental new rule for business is that the Internet changes everything.

I have been struck again and again by how important measurement is to improving the human condition.

Well, it's taken time to get this going, but he was right. If you give people a chance to associate themselves with a cause they care about, while buying a great product, they will. That was how the RED Campaign was born, here in Davos.