Ego The ego acts according to the reality principle. Since the id's drives are frequently incompatible with social reality, the ego attempts to direct its energy and satisfy its demands by the imperatives of that reality. According to Freud the ego, in its role as mediator between the id and reality, is often obliged to cloak the (unconscious) commands of the id with its preconscious rationalizations, to conceal the id's conflicts with reality, to profess…to be taking notice of reality even when the id has remained rigid and unyielding.

Originally, Freud used the word ego to mean the sense of self but later used it to include psychic functions such as judgment, tolerance, reality testing, control, planning, defense, synthesis of information, intellectual functioning, and memory.

reality. But the superego is constantly watching every one of the ego's moves and punishes it with feelings of guilt, anxiety, and inferiority. Defense Mechanisms' To overcome this the ego employs defense mechanisms. Defense mechanisms reduce tension and anxiety by disguising or transforming the impulses that are perceived as threatening.[26] Denial, displacement, intellectualization, fantasy, compensation, projection, rationalization, reaction formation, regression, repression, and sublimation were the defense mechanisms Freud identified. His daughter Anna Freud identified the concepts of undoing, suppression, dissociation, idealization, identification, introjection, inversion, somatization, splitting, and substitution.

The ego is not sharply separated from the id; its lower portion merges into it…. But the repressed merges into the id as well, and is merely a part of it. The repressed is only cut off sharply from the ego by the resistances of repression; it can communicate with the ego through the id. (Sigmund Freud, 1923) In a diagram of the Structural and Topographical Models of Mind, the ego is depicted as being half in the conscious, a quarter in the preconscious, and the other quarter in the unconscious.