In Vivo

Psychopaths Do Not Exist: The Zombie Idea Explained | Dr. Rasmus Rosenberg Larsen | Ep. 45

In Vivo

Show Notes

In this episode of In Vivo, I sit down with Dr. Rasmus Rosenberg Larsen, Assistant Professor of Forensic Epistemology at the University of Toronto and author of Psychopathy Unmasked: The Rise and Fall of a Dangerous Diagnosis (MIT Press).

Larsen challenges nearly every major claim about psychopathy: that people with high PCL-R scores lack empathy, are uniquely dangerous, are untreatable, have distinctive brains, or even form a coherent clinical category. Drawing on systematic reviews, historical analysis, and legal case data, he argues that psychopathy may be a “zombie idea”, an intuitively appealing concept that has survived despite a large body of contrary evidence.

We cover the 18th-century origins of the idea, the rise of the Hare Psychopathy Checklist, how the diagnosis is used to justify longer sentences and harsher outcomes, the famous Oak Ridge treatment study, and why figures like Ted Bundy and Adolf Hitler do not actually fit the classic profile. Larsen also discusses the ethical problems of using an unreliable tool in court and offers practical advice for clinicians, lawyers, and students.

00:00 – Introduction 01:58 – How Larsen got interested in psychopathy 04:11 – Historical origins: Benjamin Rush and “anomia” (1786) 09:30 – How psychopathy is defined today 13:13 – Why the diagnosis has unique power in court 16:31 – How the PCL-R is actually administered 28:28 – Why Ted Bundy is a poor example of psychopathy 33:03 – Does Bundy fit the classic scientific claims? 1:16:16 – What is a “zombie idea”? 1:41:23 – Genocides, ordinary people, and why they are not psychopaths 1:47:45 – Were Hitler, Stalin, or Mao psychopaths? 1:51:31 – Advice for students interested in the field 1:55:17 – Advice for clinicians, prosecutors, and defense attorneys 1:59:45 – Where to find the book and Larsen’s work

Website: https://www.rasmusrosenberg.com Book site: https://psychopathyunmasked.com Dr. Larsen’s X page: https://x.com/RasmusRosenberg Dr. Larsen’s LinkedIn: https://www.linkedin.com/in/rosenberglarsen/

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