According to Freud, human personality is divided into three fundamental structures: the Id, the Ego and the Superego. The Id is the only structure present from birth, and is driven by the instincts and immediate pleasure. In infants, for example, it is responsible for thrist or hunger. These impulses must be regulated by the <u>Ego</u>, which provides more realistic and socially acceptable alternatives. In the example, Matthew has not yet developed full control of his Ego, so the Id dictates his behaviour.
