The cluster of psychiatric concepts that includes “personality disorders,” “psychopathy” and “moral insanity” has long been controversial and uncertain. This article investigates the concept of “psychopathy” in 1950s England and shows how this ambiguity is not a flaw or failure in the concept but absolutely necessary for the role it carries out: policing broad areas of social life. A case of Munchausen syndrome (a type of “psychopathy”) in the late 1950s still functions as a precedent in the welfare system today, denying claimants sickness benefit, “closing a loophole,” and exemplifying the usefulness of this uncertainty.
