Dialogues between philosophy and psychiatry: The case of dissociative identity disorder

Abstract

In psychiatry, as in any other medical specialty, the clinician collects information from the patient's anamnesis, clinical observation, and diagnostic tests; evaluates these data; and makes a diagnosis. The most common manuals used to assess a patient's mental disease according to his or her symptoms are the Diagnostic and Statistical Manual of Mental Disorders (DSM) and the International Classification of Diseases (ICD). This chapter focuses on the dialogue that philosophy and psychiatry have held for decades to achieve a better understanding of dissociative identity disorder (DID). The outcome of this dialogue is the expression of the diagnostic criteria for DID, as well as other dissociative disorders, in the medical manuals. Thus, we first analyze the evolution of DID across the different versions of ICD and DSM. We then show that the characterization of DID and other dissociative disorders is a lively debate that is far from being settled. We demonstrate that the core of this debate is the understanding of person after John Locke's philosophy: A person is defined by the apparent expression of consciousness and memories. This leads to what we have termed a primary conceptual dissociation: The mental qualities of the person are dissociated from the body. We propose an alternative account based on the dynamic nature of identity and the understanding of person as a mind-body unity. We hope that our proposal, which results from the interdisciplinary dialogue between psychiatry and philosophy, contributes to a better understanding of this disorder and its underlying concepts.