We all like to think we have a hidden inner life. Most of us assume that our beliefs and desires arise from the murky depths of our minds, and, if only we could work out how to access this mysterious world, we could truly understand ourselves. For more than a century, psychologists and psychiatrists have struggled to discover what lies below our mental surface.

In The Mind Is Flat, pre-eminent behavioural scientist Nick Chater reveals that this entire enterprise is utterly misguided. Drawing on startling new research in neuroscience, behavioural psychology and perception, he shows that we...