Abstrakt
Delusions are one of the main symptoms of psychotic disorders. However, their definition depends on the subjective understanding of the psychiatrist and thus may significantly vary (Garety & Freeman 1999).
International Classification of Diseases (World Health Organization 2004) or the Diagnostic and Statistical Manual of Mental Disorders, vol. V (American Psychiatric Association 2013) provide only general descriptions.
The reason is that delusions are connected to the content of the patients mental world, and thus always specific. Or is it possible to describe structures of delusions without being too general? Semiotics offer theoretical perspective through which we can analyse mental phenomena as signs.
Charles Sanders Peirce introduced taxonomy of signs and their specific aspects in his comprehensive theory of semiotics (Peirce 1932). Using this taxonomy as a methodological framework, we can distinguish sign structures of mental phenomena, their relations, characteristics or interpretations.
This presentation aims to outline sign structures of different types of delusions. Delusions may be divided into several topic-related types: erotomanic, grandiose, jealous, somatic etc. (American Psychiatric Association 2013: 90-91).
I shall argue that in any of these types, the central theme of the delusion is always connected to the self in a structure of a proposition. Delusionary system of beliefs built around this central proposition is based on inferences that combine this proposition with other (often realistic, perceptory) propositions in a structure of an argument.
At the same time, the central proposition itself is not a subject of argumentative falsification. This difference from other beliefs is characteristic for delusions.