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.

You need to understand things in order to invent beyond them.

Giving money effectively is almost as hard as earning it in the first place.

I don't think I would have spent time learning about the immune system if understanding vaccines weren't something I considered very important.

My son likes to go see mines and electric plants, or the Large Hadron Collider, and we've had a chance to see a lot of interesting stuff.

In most of these things our foundation is a co-funder, so I can say that a polio or an HIV vaccine, that I'm putting our resources behind it in a very big way and the U.S. government would be the best partner for those efforts.

We all know that there are these exemplars who can take the toughest students, and they'll teach them two-and-a-half years of math in a single year.