How the concept of the self is related to that of the ego has been discussed ever since Hartmann introduced the concept of self into psychoanalytic theory. It is assumed that the concept of the ego cannot explain all psychic phenomena—especially those falling within the general psychoanalytic psychology of development. On this assumption, the author discusses the relationship between the ego and the self, in the sense that the latter is distinguished by its representational qualities while the former, an organ of the self, is defined solely by its functions.