Reward worthy failure - Experimentation.

It was really phenomenal [Warren Buffett donation]. It grew out of the friendship that we had and the fact that his plan to have his wife run the foundation and give things away changed when she tragically died.

In the decade ahead I can predict that we will provide over twice the productivity improvement that we provided in the '90s.

OK, I have a nickname. My family calls me 'Trey' because I'm William the third. My dad has the same name, which is always confusing because my dad is well known, and I'm also known.

Bitcoin is mostly about anonymous transactions, and I don't think over time that's a good way to go. I'm a huge believe in digital currency... but doing it on an anonymous basis I think that leads to some abuses, so I'm not involved in Bitcoin.

I considered law and math. My Dad was a lawyer. I think though I would have ended up in physics if I didn't end up in computer science.

If somebody is considering being willing to go out and work in the field in global health, those are a particular class of heroes because it's hard to work in those places. Our foundation gets so many of our learnings from people who've been out there and seen, "this tool is not going to work there, there's more of a problem here than you know." You should really get involved in that.