Describe the id, ego, and superego in Macbeth.
In Freudian theory, the id is that which manifests the unconscious primal urges, like power, sex, dominance, immediate gratification. Lady Macbeth's speech before she coerces Macbeth--through a scolding about promises being broken--into the murder of Duncan strongly exhibits characteristics of the Freudian id construct. Lady Macbeth shows unrestrained primal urge for power and self-satisfaction regardless of the existence of any higher laws or principles.
The superego is the monitor and evaluator of an individual's actions, thought and other behaviors, the "parenting" force of the psyche. Later in the play, when Lady Macbeth quails at the deed, her superego gets the better of her and, at Duncan's resemblance to her father, instills her with a sense of guilt. Macbeth, himself, is frequently in conversation with his superego while he tries to sort out what to do and why to do it or not do it.
The ego is the integrated psyche of the personality, that which rationally and emotively interacts with and reacts on the conscious level to the reality it is immersed in. One can argue that Macbeth's reaction to the witches first visitation was a function of his ego trying to find a regulatory balance between the apparent reality presented by the witches and the true reality he had experienced and that he anticipated going forth for him after the battles and Duncan's decisions. One could say that after all is done and Banquo's ghost has haunted him precipitating his loss of sanity, that Macbeth's id has full sway: he revisits the witches for the instant gratification of comfort (never mind it was an irrational act seeking aid from the trouble makers...); he endlessly recites that he is impermeable because of their prophecies; he irrationally orders senseless murders; he ranks and raves while awaiting his terrible end.