The article examines the cognitive function of the lexical and grammatical categories of languages. The author conducts the study of the field of cognitive linguistics, and in particular, the cognitive function of an object in connection with the philosophy of the language. The comparison of the results of studying lexical and grammatical categories (names, numbers) is given. Attention is paid to the function of the logic of statements as a proposition of the cognitive approach. The principles and differences, changes of categorization and grammatical status of categories are revealed, the procedural nature of cognitive processes is substantiated.