Plenty of crime dramas and horror films feature a psychopath on a rampage. That diagnosis, however, might be the real fiction. Rasmus Rosenberg Larsenis is assistant professor of forensic epistemology and philosophy of science at the University of Toronto Mississauga in Canada and an affiliated scientist at the National Center for Ontological Research in the U.S. He is also the author of “Psychopathy Unmasked: The Rise and Fall of a Dangerous Diagnosis.” He joins host Krys Boyd to discuss why psychopathy isn’t real, how that diagnosis came about, and why even serial killers don’t have all the traits we assume they do. His companion piece to his book, “There are no psychopaths,” was published in Aeon.