Larry Brilliant is a doctor, co-founder of the digital social network the Well, and he was the first executive director of Google.org. But back in the Sixties, he was a hippie doctor who joined Wavy Gravy's traveling bus caravan and then landed in an Indian ashram in the Himalayas, where his guru told him his destiny was to help cure smallpox. Miraculously, his U.N. team of doctors eradicated the world's remaining cases of this terrible disease. He tells Steve Paulson about a remarkable moment in history when anything seemed possible.