Sigmund Freud’s personality theory is commonly called the iceberg theory. Freud suggests that the id is present at birth. The id never goes outside of the unconscious level, and follows the pleasure principle. It demands instant gratification of instincts without consideration of needs of others, law, or social custom. The ego begins at the age of one. The ego stands for good sense and reason. The ego curbs that appetite of the id, so it fits social conventions. The ego is guided by the reality principle; it takes account what is practical with what is urged by the id. The super ego develops during the early childhood. During this stage the child incorporates the moral values and standards modeled by the parents, which is the identification process.
Freud’s theory is composed of five stages. The first stage is oral; the stage where gratification is obtained through oral activities, in the first year of life. The second stage is anal; the stage where sexual gratification is met through contraction and relaxation of muscles that control the elimination of waste products in the second year of life. The third stage is phallic; a shift of libido to the phallic region, in the third year of life. The fourth stage is latency; sexual feelings remain unconscious in the fifth or sixth year of life. The fifth stage is the genital stage; expression of libido through intercourse, attained in the adolescence stage.
Erick Erickson’s personality theory is proposed of psychosocial development. The stages start during infancy, with trust vs. mistrust; early childhood, with autonomy vs. shame and doubt; preschool, with Initiative vs. guilt; elementary, with Industry vs. inferiority; Adolescence with, Ego Identity vs. Role Diffusion; Young Adulthood with, Intimacy vs. Isolation; Middle Adulthood with, Generativity vs. Stagnation; and Late Adulthood with, Integrity vs. Despair. Erickson suggests that the goal of adolescence is to attain ego identity.