My dream is to find individuals who take financial resources and convert them into changing the world in the most positive ways.

When we were walking through the narrow alleys [of the Mathare Valley slums], it was literally impossible not to step in the raw sewage and the garbage alongside the little homes. But at the same time it was also impossible not to see the human vitality, the aspiration and the ambition of the people who live there.

The only way we really create change is to enter any situation with the humility to listen and to recognize the world as it is, and then the audacity to dream what it could be, to have the patience to start and let the work teach you, to be willing to lead when you need to lead, and to listen. To have a sense of generosity and empathy, but not over-empathy, because accountability is so critical to building solutions that work.

You should focus on being more interested than interesting.

If indeed we can create systems that allow individuals to access goods and services like health and housing and energy and water, in a way that they can afford, they'll all have greater choice, greater opportunity, greater dignity.

I feel like I'm a relentless, pragmatic, determined optimist.

Why do some people stop growing at age 30, just going from work to the couch and television, when others stay vibrant, curious, almost childlike into their nineties?