How do we reclaim our innate enchantment with the world? And how can we turn our natural curiosity into a deep, abiding love for knowledge? Frank Oppenheimer, the younger brother of the physicist J. Robert Oppenheimer, was captivated by these questions, and used his own intellectual inquisitiveness to found the Exploratorium, a powerfully influential museum of human awareness in San Francisco, that encourages play, creativity, and discovery—all in the name of understanding. In this elegant biography, K. C. Cole investigates the man behind the museum with sharp insight and deep sympathy. The Oppenheimers were a family with great wealth and education, and Frank, like his older brother, pursued a career in physics. But while Robert was unceasingly ambitious, and eventually came to be known for his work on the atomic bomb, Frank's path as a scientist was much less conventional. His brief fling with the Communist Party cost him his position at the University of Minnesota, and he subsequently spent a decade ranching in Colorado before returning to teaching. Once back in the lab, however, Frank found himself moved to create something to make the world meaningful after the bombing of Hiroshima and Nagasaki. He was inspired by European science museums, and he developed a dream of teaching Americans about science through participatory museums. Thus was born the magical world of the Exploratorium, forever revolutionizing not only the way we experience museums, but also science education for years to come. Cole has brought this charismatic and dynamic figure to life with vibrant prose and rich insight into Oppenheimer as both a scientist and an individual.