Case systems of Turkic languages of Southern Siberia (comparison with geometric modeling)

The subject of the article is a comparison of the case systems of the agglutinative Turkic languages of Southern Siberia with the aim to establish their typological commonality and differences. The method of case systems geometric modeling allows us to clearly demonstrate the semantic oppositions of case forms in a selected language and compare differences in the semantic structure of case systems of both related and non-related languages. The main result of the study is the establishment of a direct relationship between the case category, the language morphological type and the canonical structure of a typical utterance in each language and an indirect relationship with the typical conditions of communication in a language community. The study showed that the case systems of the considered languages contain the optimal composition of paradigm elements in the communicative conditions typical for agglutinative languages. Speakers of agglutinative languages have common generic and individual images, and in a particular situation, communicants are aware of the subjects and objects mentioned in the utterance, which allows using case forms to express not only the main actant roles, but also additional components of grammatical meanings. The results obtained can be used primarily in systemic typology, as well as in Turkic studies.