This article analyzes the establishment of the concept of ego in Freudian metapsychology in Project for a Scientific Psychology (1895), and then the "return" in his writings on narcissism and the topical reformulation in The ego and the id (1923), due to Beyond the pleasure principle (1920). This essay indicates the relations between the concept of ego and important theoretical fundaments, as topical and drives theories. Therefore, submitting the concept of ego to an investigation capable of detecting its guiding principles is an important tool for the purpose of analyzing some ambiguities in Freud's theory.
Epistemology; psychoanalysis; metapsychology; ego