Hervey M. Cleckley

Hervey Milton Cleckley was an American psychiatrist and pioneer in the field of psychopathy. His book, The Mask of Sanity, originally published in 1941 and revised in new editions until the 1980s, provided the first clinical description of psychopathy. He defined the term somewhat more broadly than it is understood today, as referring to somebody who behaves in a destructive manner despite lacking overt signs of psychosis or neurosis; this is reflected in the term "mask of sanity", derived from Cleckley's belief that a psychopath can appear normal and even engaging, but that the "mask" conceals a mental disorder. By the time of his death, Cleckley was better remembered for a vivid case study of a female patient, published as a book in 1956 and turned into a movie, The Three Faces of Eve, in 1957. His report of the case (re)popularized the diagnosis of multiple personality disorder in America. The concept of psychopathy continues to be influential through forming parts of the diagnosis of antisocial personality disorder, the Psychopathy Checklist, and public perception.