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.

1.5 billion people lack proper access to electricity. Many buy kerosene, which can cost 30 percent of their income. It sends millions of metric tons of carbon dioxide into the atmosphere every year. And often the lamp will fall over and catch the house on fire. So mothers hate it, but it's their only option.

I have also been touched by the dark side of power and leadership.

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?

A sustainable world means working together to create prosperity for all.

I have seen that traditional approaches to charity and aid don't solve problems of poverty. In fact, too often they create dependence.

I've learned that there is no currency like trust and no catalyst like hope. There is nothing worse for building relationships than pandering, on one hand, and preaching, on the other. And the most important quality we must all strengthen in ourselves is that of a deep human empathy, for that will provide the most hope of all and the foundation for our collective survival.