The book explores remarkable cases of patients who demonstrate how our impression of reality is created by the brain. Age-old questions about dreams, colour perception, phantom sensations and hallucinations are illuminated by surprising discoveries from the latest brain research. How does consciousness differ from memory, emotions and behaviour? How did it develop during the evolution of life on earth, and does it serve a purpose? Does the brain leave room for free will? In this unique blend of philosophy, history, psychology and neuroscience, Cyriel Pennartz breaks new ground by presenting an original theory of brain and mind, substantiated by brain research in patients and healthy people. This theory, inspired by the seventeenth-century philosopher Spinoza, goes significantly deeper than current thinking based on computer models or artificial intelligence. is essential reading for students working at the interface of neuroscience, cognitive psychology, philosophy of mind and cognitive science, as well as anyone interested in consciousness and the brain.