The construct ‘personality functioning’ is currently not logically defined

Since its introduction in the DMS-5 Alternative Model of Personality Disorders (AMPD), the construct of ‘personality functioning’ has been tasked with two key aims in order to define the dimensional concept of personality disorder. The first aim of personality functioning was to integrate the major dimensions of personality pathology in order to capture what is “common to all personality disorders” (Bender, Morey, and Skodol 2014). The second aim of personality functioning was to differentiate personality disorder from other mental disorders by clarifying “what is personality disorder from what is not” (Morey 2019). In this viewpoint, we argue that these two aims–––-integration vs. differentiation–––-are diametrically opposed, leading to an incoherent definition of dimensional personality disorder (and, by extention, all mental disorder).