The psychopath is a historically ill-defined and overused diagnostic category. This paper analyzes the discursive development and cultural permutation of the psychopathic personality within psychiatry and law to reveal not just the categorical flexibility but also the categorical fragility of the psychopathic person. The discourse of psychopathy relies on our understanding that the identity must be assigned to another person, for what makes the psychopath’s mental deficiency so threatening is his inability to empathize and care about his condition. Within the last five years, the discourse has noticeably shifted as people ask the question: “Am I a psychopath?” In posing this paradoxical concern, the functionality of the psychopathic identity shifts from the psychopathic Other to the psychopathic Self. This shift reconfirms the categorical pliancy of the psychopath and, furthermore, complicates what it means to “know thyself.” In examining self-knowledge formation in the context of Foucault’s essay “Technologies of the Self,” we can see how the discursive power of the psychopath dilutes and condenses through self-diagnosis.