Abstract
Initially, some arguments are brought forward why, at the present state of differential diagnosis, it is useful to apply the term schizo-affective disorder. The basic considerations concern the consequences of the semantic confusion between mood and affect and how this affects differential diagnosis of functional psychoses. The view is maintained that from an action theoretic model mood states have to be conceptualized as differing forms of pragmatics of reality creation and self-interpretation (in other words, as multilogic of self-observation, self-protection, self-repair, and of the relativistic and reflective structure of inter- and intrapersonal communication). The concept of mood congruen-cy/incongruency is meaningful only as a metaconcept in regard to emotional connotation, perceptive operations, cognitive processes, nonverbal expressions, autonomic parameters, and so on.