Locked in the dark chamber of your skull, your brain fashions the rich narratives of your reality and your identity. But what is reality? Who is the real you? How do you make decisions? Why does your brain need other people? And how is technology poised to change what it means to be human? In this illustrated companion volume to his PBS/BBC television series, neuroscientist David Eagleman delves into the questions at the heart of our existence. He explores topics like extreme sports, criminal justice, facial expressions, genocide, brain surgery, gut feelings, robotics, and the search for immortality, revealing how life shapes your brain, just as your brain shapes your life.