Ego, in classical psychoanalysis, is the portion of the personality that mediates between an individual's biological drives and the obstacles to those drives that are presented either directly or indirectly by the environment. Of the other uses of the term, the most important is that current in analytical psychology, which defines the ego (from Latin ego, meaning "I") as the individual's awareness of his continuing selfhood. The functions of the ego, which has both conscious and preconscious components, comprise sensory perception, thinking (including distinguishing between objective and subjective reality), memory, and voluntary motor control.
The Concept of the Ego
The concept of the ego was first developed by Sigmund Freud around 1895, but it was clarified in its present form only with the publication of Freud's The Ego and the Id in 1923. Freud held that personality consists of three portions: the id, the ego, and the superego. The id, which is the reservoir of biological impulses, constitutes the entire personality of the infant at birth. Its principle of operation, to guard the person from painful tension, is termed the pleasure principle. Inevitable frustrations of the id, together with what the child learns from his encounters with external reality, generate the ego, which is essentially a mechanism to minimize frustrations of the biological drives in the long run. It operates according to the reality principle. Freud held that the ego had no energy of its own, its dynamics originating in the id. The superego comprises the conscience, a partly conscious system of introjected moral inhibitions, and the ego-ideal, the source of the individual's standards for his own behavior. Like external reality, from which it derives, the superego often presents obstacles to the satisfaction of biological drives. In general, the function of the ego is to find ways in which such drives can be satisfied within the limitations imposed by the conscience, so as to relieve physical tensions without incurring guilt.
The ego adopts various means to perform its task. Most commonly, the discharge of an impulse originating in the id is simply postponed until the situation is suited to it. In many cases, however, such an impulse can never be discharged directly, and the ego must utilize one of many defense mechanisms in order to protect itself from conflict. It may succeed in transforming the impulse so that it may be expressed without danger to the individual; otherwise, the impulse may be repressed, in which case its psychic energy accumulates as tension within the personality. When such tensions become excessive, because of deficiency in the ego or external circumstances, neurosis or psychosis result.
Later psychologists have altered or abandoned Freud's conception of the ego. Some neo-Freudians consider the ego in some sense autonomous and maintain that it functions sometimes to satisfy its own needs, not exclusively those of the id. Among non-Freudian conceptions of the ego, that of the social psychologists Muzafer Sherif and Hadley Cantril defines it as a set of attitudes such as "what I think of myself, what I value, what is mine and what I identify with." Gordon Allport, a psychologist of personality, distinguished the ego as a process from the ego as an object of knowledge, anticipating the distinction by a later writer (Isidor Chein) between the ego and the self.