Our teachers deserve better feedback.

If somebody is working on a new medicine, computer science helps us model those things. We have a whole group here in Seattle called the Institute for Disease Modelling that is a mix of computer science and math-type people, and the progress we're making in polio or plans for malaria or really driven by their deep insights.

Philanthropy should be taking much bigger risks that business. If these are easy problems, business and government can come in and solve them.

There were a lot of missteps in the early days, but because we got in early we got to make more mistakes than other people.

I have drifted away from thinking about these philanthropic things. And it was only as the wealth got large enough and Melinda and I had talked about the view that wealth wasn't something that would be good to just pass to the children.

We really have to work hard to remind people even though this is far away, that's it's probably the most generous thing governments have ever come together to do. Since World War II, this new institution is the only one that's emerged and is saving all these lives.

The part of uranium that's fissile - when you hit it with a neutron, it splits in two - is about 0.7%. The reactors we have today are burning that 0.7%.