What is the material basis of the thoughts that occur inside our heads? Where do imaginative, creative, or spiritual thoughts come from - can these really be the product of nerve impulses in the brain? And is the human mind radically different from that of other species, or is our uniqueness more superficial than real? In this book, Oxford biologist John Parrington proposes a radical new theory of human consciousness, arguing that a qualitative leap in consciousness occurred during human evolution as language and tool use transformed our brains. Rejecting outdated views of the brain as a hard-wired circuit diagram, he draws on the latest insights from neuroscience to show that meaning is created within our heads through a dynamic interaction of oscillating brain waves. This new model of consciousness not only provides a material basis of our innermost thoughts but also explains why the mind can sometimes go wrong, causing deep mental distress.