The article points out that, solving the problem of society and the aggregate as an object of science, Kondratiev develops a methodology for determining the essence of such a aggregate as society. To this end, through a system of definitions of the aggregate, he clarifies the most important parts of its structure and their most important qualities (a large number of elements, the elements themselves, their real connections and relationships, phenomena as the results of connections and interactions). In addition, through certain categories, he reveals the forms of knowledge about the aggregate, displayed in the concepts of discreteness, true objective reality, causally necessary connections, relationships, series. The latter are expressions of knowledge about uniform connections and relationships between elements and phenomena of the aggregate.