My wife thinks she's better than me at puzzles. I haven't given in on that one yet.

Don't let complexity stop you. Be activists. Take on the big inequities. It will be one of the great experiences of your lives.

Great organizations demand a high level of commitment by the people involved. Eliminate politics, by giving everybody the same message. Keep a flat organization in which all issues are discussed openly. Empower teams to do their own things.

I believe it’s not only possible to eradicate malaria; I believe it’s necessary. Ultimately, the cost of controlling it endlessly is not sustainable. The only way to stop this disease is to end it forever.

The PC has improved the world in just about every area you can think of. Amazing developments in communications, collaboration and efficiencies. New kinds of entertainment and social media. Access to information and the ability to give a voice people who would never have been heard.

Unfortunately, the highly curious student is a small percentage of the kids.

So on the demand side [for energy], there have been a variety of policies that globally have been way over $50 billion a year of tax credits, raising the price of electricity through things like renewable portfolio standards, so the total amount of money that's gone into sending a price signal to push up demand versus what would happen without it has been gigantic.