After Freud discovered an unconscious system (Ucs) between 1894 and 1896, a window opened for him to formulate a comprehensive theory of the human psyche, which he called psychoanalysis. The Ucs was its foundation. The object relations theories, ego psychology, self-psychology, and their offshoots managed to erode that concept from the theory in different ways and tried to replace psychoanalysis. The reason is that Freud, for a long time, associated the unconscious with the repressed. It was possible by reviewing his work in the field of repression, defense, and the unconscious to uncover the nature of the system Ucs It is not possible for a school of psychology within psychoanalysis to ignore the systemic unconscious and replace it with a dynamic unconscious and still claim that it is psychoanalytic.