Doing something that has never been done before is terrifying… all the people who love you will tell you not to do it… not because they're jealous, but because they're genuinely scared for you… they're worried for your wellbeing.

Most people think of optimism as a celebration, but for us optimism is a courageous choice to remain grittily determined to find solutions in a timely and collaborative way. We have no choice but to address climate change, and thus we have no choice but to remain stubbornly optimistic.

There are two key features of blockchain that make it, potentially, a very useful technology from an economic perspective. First, the data about transactions are posted on many public sites thus giving these data an immutability that makes disputes easy to avoid. Second, although the data are in some sense public, they can be encrypted so that a particular party learns only those aspects that she needs to know.

Are you the guy who wants to know what he gets at the end of the month? Or are you the guy who says I'll take my chances and will do very well or very badly. If you can make that distinction in your own mind, the rest is up to you. That's where entrepreneurship comes from; it means you can live with risk.

To me it was a great revelation to find creativity in the midst of something that was not thought of as being creative.

We need a blue revolution to match the green revolution. This means investing in water infrastructure, technology, and governance with the same urgency we once applied to food security.

I was at one of our schools in Kenya recently, I was just chatting away to a group of children about all the things we had seen that day- the lions and how lucky they are to be sitting next to Meru National Park, and I said 'would anyone like to ask me a question?'. Suddenly this little boy put up his hand and he said 'please miss, why do men kill lions?'. Well, I could have hugged him if he wouldn't have been mortified with embarrassment.

I think it's that dynamic of information coming from your trusted peer. This has always been the source of the most trusted information. Your reinforcement is coming from people that you like, people that you trust. And you're shaping and having that discussion amongst yourselves.

Because it's giving us information about how we're feeling and what we need to do about those feelings. When I'm looking at your facial expressions, I get signals—like either you're interested or you're bored. Either you want me to keep going or not. And that's data for me. Because if I notice a shift in the way you're engaging with me while I'm speaking, I could either use that information, or I could keep going and going and going, and then lose my audience.

The miracle of capitalism is that if you have a central government trying to solve something, it will come up with one averagely optimal solution for everybody. And capitalism will come up with 10 different solutions to the same problem.

Skiing gave me purpose, and a goal. As a kid, there are so many distractions, and so many different paths to take. I saw a lot of my friends, who were perhaps more talented than I was, without the same goals and determination- and it caused them to veer off course.

One of the best ways to make money is not to lose it. If you can learn not to lose money, you're making money. When you lose your own money, it hurts, it makes you careful, but you cannot let it take the mojo… the hunger out of you.