Id, ego, and super-ego

Id, ego, and super-ego are the three parts of the psychic apparatus defined in Sigmund Freud's structural model of the psyche; they are the three theoretical constructs in terms of whose activity and interaction our mental life is described. According to this model of the psyche, the id is the set of uncoordinated instinctual trends; the super-ego plays the critical and moralizing role; and the ego is the organized, realistic part that mediates between the desires of the id and the super-ego. The super-ego can stop one from doing certain things that one's id may want to do.

Although the model is structural and makes reference to an apparatus, the id, ego and super-ego are purely psychological concepts and do not correspond to (somatic) structures of the brain such as the kind dealt with by neuroscience. The super-ego is observable in how someone can view themselves as guilty, bad, pathetic, shameful, weak, and feel compelled to do certain things. Freud (1923) in The Ego and the Id discusses "the general character of harshness and cruelty exhibited by the [ego] ideal – its dictatorial 'Thou shalt.'"

Freud (1933) hypothesizes different levels of ego ideal or superego development with increasingly greater ideals:

...nor must it be forgotten that a child has a different estimate of his parents at different periods of his life. At the time at which the Oedipus complex gives place to the super-ego they are something quite magnificent; but later they lose much of this. Identifications then come about with these later parents as well, and indeed they regularly make important contributions to the formation of character; but in that case they only affect the ego, they no longer influence the super-ego, which has been determined by the earliest parental images.

The earlier in development, the greater the estimate of parental power. When one defuses into rivalry with the parental imago, then one feels the 'dictatorial thou shalt' to manifest the power the imago represents. Four general levels are found in Freud's work: the auto-erotic, the narcissistic, the anal, and the phallic. These different levels of development and the relations to parental imagos correspond to specific id forms of aggression and affection. For example, aggressive desires to decapitate, to dismember, to cannibalize, to swallow whole, to suck dry, to make disappear, to blow away, etc. animate myths, are enjoyed in fantasy and horror movies, and are observable in the fantasies and repressions of patients across cultures.

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