Bill Gates

Governments will always play a huge part in solving big problems. They set public policy and are uniquely able to provide the resources to make sure solutions reach everyone who needs them. They also fund basic research, which is a crucial component of the innovation that improves life for everyone.

When people said Africa would change me, I didn't understand what they meant. To see the poverty in the townships, for instance, is overwhelming. I found it heart-wrenching to see young children walking barefoot and hungry in the dirt. I'm the kind of person who wants to change the world right here and now, so I got frustrated.

Leverage is great when it works, and when it doesn't work, it creates a lot of issues. So I think if you limit the amount of leverage that people can borrow, or that banks can borrow, I think you'll find that you'll have a lot less issues going forward.