As his point of departure Horn takes the decisive anthropological theories which hold that 'human nature' is understandable only within the context of its societal and historical aspects. Thus, 'first' nature is manifest only within the medium of 'second' nature. On the basis of this thesis, Horn aims his criticism in two directions: 1, toward psychoanalytic theory for attempting to construct naturalistic concepts (e.g., the theory of aggression) that have no connection with therapeutic practice and that do not deal adequately with metapsychological societal problems (e.g., war); and 2, toward certain sociological theories that tend to deny the element of human animality which escapes full integration in the various forms of societal structure.