If you're using first-class land for biofuels, then you're competing with the growing of food. And so you're actually spiking food prices by moving energy production into agriculture.

Getting the word out that, yes vaccines are great, the safety data's very, very clear, including any of these specific concerns, that's very important to our foundation.

If you think of global public goods like polio eradication, the kind of risk-taking new approach, philanthropy really does have a role to play there, because government doesn't do R&D about new things naturally as much as it probably should, and so philanthropy's there.

Even when things are stable, that's not easy [to work in Africa] because there are not roads, and the weather is tough, the education system hasn't been there. But this is how you get great countries, is step by step.

Over 80% of the poor are people who have small plots of land and grow their own food and they don't grow enough to sell much into the marketplace. So they will be hit hard by the worst in climate. They really get hit hard starting in the 20-year time frame and thereafter.

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.

The world is progressing and resources are becoming more abundant. I'd rather go into a grocery store today than a king's banquet a hundred years ago.