Matt Damon: ‘You will never solve poverty without solving water and sanitation.’

In 2007 he was named People magazine’s Sexiest Man Alive, but these days, Matt Damon is getting noticed for something far less sexy. “Probably the least sexy thing is water,” says Damon. “But, you know, it’s a huge issue for women and girls, and they’re the ones affected the most. And, as a father of four girls, I feel it personally.”

Edward Norton is a Hollywood A-lister with memorable roles in “Primal Fear,” “Fight Club” and “American History X.” He’s also a passionate philanthropist with an entrepreneurial spirit. After running the New York City Marathon for charity in 2009, he got the idea of developing an online platform that would combine fundraising with social media; soon after he co-founded Crowdrise.

These are the two magic words that have led to some of the most profound and game-changing innovation in history: “What if?” And with my new digital series “World 3.0,” I’ll speak with some of the men and women who have asked that question in tech, science, medicine, business and philanthropy and have found answers that improved — and in some cases disrupted — their industries.