The most straightforward path would be if we could bring the cost of solar electric and wind down by another factor of say, three, and then have some miraculous storage solution, so that not only over the 24-hour day but over long periods of time where the wind doesn't blow, you have reliable energy. That's a path. But energy storage is hard. That's not a guaranteed path.

In this business, by the time you realize you're in trouble, it's too late to save yourself. Unless you're running scared all the time, you're gone.

There won't be anything we won't say to people to try and convince them that our way is the way to go.

Like my friend Warren Buffett, I feel particularly lucky to do something every day that I love to do. He calls it "tap dancing to work."

My parents are very successful, and I went to the nicest private school in the Seattle area. I was lucky. But I never had any trust funds of any kind, though my dad did pay my tuition at Harvard, which was quite expensive.

The pace of progress in biology creates a foundation that naturally gets picked up by the biotech and pharmaceutical industry to solve rich-world diseases. This is attractive science. It's science that people want to work on.

Well depending on the government, you either work through the government, which is ideal, because then you're strengthening their capabilities, or you work through the non-governmental organizations. It's never easy, and you know, it's just about the very basics of health. This is not hospitals. This is just primary health care [in Africa], the most simple things, and even so, getting the supplies out, getting the trained workers there.