What leads reasonable, intelligent, scientifically curious people to believe the Earth is flat? Self-delusion expert and psychology nerd David McRaney sets out to discover not just what it takes to influence others, but why we believe in the first place. Along the way he meets a former Westboro Baptist Church member who was deradicalised on Twitter, goes deep canvassing to see how quickly people will surrender their character-defining views, finds a 9/11 Truther who turns his back on it all, and interviews a prominent Flat Earther in front of a live audience. Drawing on the latest research in psychology and neuroscience, How Minds Change explains, well, how minds change – and how to change them – not over hundreds of years, but in less than a generation, in less than a decade, and sometimes in a single conversation.