Seamlessness in personality and its derangements.

A significant but often overlooked aspect of the circumplex structure of the domain of interpersonal functioning is its systematically continuous ordering of the quality of the behavioral variations addressed. It is a domain, in other words, explicitly lacking in categorical boundaries wherein a given behavior can be sharply discriminated from others proximal to it within a shared circumplex space; any identified border is at best a "fuzzy" one characterized by blending and interpenetration. It is argued that this observation has extended generalizability in respect to the organization of personality, rendering moot and suspect taxonomic systems that postulate categorical entities. The Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) used in the "diagnosis" of purported derangements of personality is one such system, one that would therefore be expected to yield certain predictable anomalies. These problems are illustrated with reference to the widespread occurrence of artifactual "comorbidities" among psychiatric diagnoses.