John Cunningham Lilly (January 6, 1915 – September 30, 2001) was an American physician, neuroscientist, psychoanalyst, psychonaut, philosopher, writer and inventor. He was a member of a generation of counterculture scientists and thinkers that included Ram Dass, Werner Erhard and Timothy Leary, all frequent visitors to the Lilly home. He often stirred controversy, especially among mainstream scientists.