The article examines the issues of systemic semantic organization of vocabulary from the point of view of how they reflect the principles of categorization of knowledge about reality. Different principles that underlie the systemic organization of semantic paradigms of different types are shown. Some principles of categorization are reflected in the semantic structure of a single word, as well as a specific paradigm that captures the result of categorization of one fragment of reality. It is shown that the principles of knowledge categorization in this case reflect the objective features of the denotation in its perception by consciousness. Other principles of knowledge categorization are revealed when comparing different types of semantic paradigms (lexical-semantic group, lexical-semantic field, associative-semantic field, derivational-semantic field), including those that categorize knowledge about the same denotative field. The principles of categorization, identified on the basis of a comparison of interword semantic relations within the framework of paradigms of different types, are to a greater extent universal and relate to the cognition of any or many denotative areas. A comparison of relationships between lexical units in different types of semantic paradigms confirms the fact of multiple categorization of knowledge about the same reality as a principle of categorization of knowledge about the world. This conclusion follows from the picture of multiple intersections of different types of paradigms, which include the same lexical units. Comparison of systemic organization of semantic paradigms of different types more fully reveals the mechanism of systematizing activity of consciousness – categorization and conceptualization of knowledge in the world picture of linguistic community.