The paper offers a semiotic interpretation of common characteristics of five domains that define the schizophrenia spectrum disorders. The questions are: Why do seemingly different types of symptoms as delusions, hallucinations, disorganized thinking, motor behavior abnormalities or negative symptoms appear in clusters? What do they have in common? The main thesis states that these types of symptoms are manifestations of a disorder on a core level of meaning-making.
Signs of the Umwelt are given meaning by a relationship to sign complex of the self. When the sign complex of the self is disrupted, the meaning-making fails.
Methodology of this study is based on semiotics of Charles Sanders Peirce. For Peirce, signs are mainly relations between elements.
When we make a semiotic reduction, we can delimit specific signs as manifestations of symptoms of mental disorders, i.e. such signs that are different from common sense, abnormal. Benefit of this approach is that we can describe as signs very different phenomena such as complex deductions on the one hand, and emotional responses on the other.