How is consciousness possible? What biological purpose does it serve? Why do we value it so highly? In 'Soul Dust' the psychologist Nicholas Humphrey, a leading figure in consciousness research, returns to the front-line with a startling new theory. Consciousness, he argues, is nothing less than a magical-mystery show that we stage for ourselves inside our own heads. This self-made show lights up the world for us, making us feel special and transcendent.