Abstract
<jats:p>The article examines reasoning texts as an autonomous functional-semantic type of scientific discourse. Reasoning is interpreted not as an auxiliary component of argumentation or logical proof, but as a structurally and communicatively coherent textual form aimed at the step-by-step conceptual development of scientific knowledge. The study describes the internal structure of reasoning texts, their theme–rheme organization, as well as their logical-semantic and syntactic features. It is shown that the presence of a thesis-centered core and a functionally organized argumentative block ensures textual integrity and allows for the representation of both the result and the process of scientific thinking. Special attention is paid to the typological relevance of the variability of theme–rheme progression in reasoning texts, which reflects the cognitive orientation of scientific discourse toward demonstrating the process of conceptual inquiry. The findings contribute to refining the functional-semantic typology of scientific texts and may be applied in studies of academic discourse and academic writing.</jats:p>