Erik H. Erikson (1902-1994) developed a modern way of rule-order model of linear development patterns, where continuity and predictability of business conditions are assumed, so that subjective self-discovery can succeed. In his theory of psychosocial stages of personality development, Erikson considered the integration of the personality as the ultimate stage of development. He conceived the process of forming a personal identity as an intermediate stage of adolescence, and a pathway for achieving it. For him, the personality of the individual is born of the relationship between personal expectations and limitations of the cultural environment. For Erikson, life revolves around the person and the environment. Thus, each step is a step forward, stagnation or retrogression compared with the other stages.
His idea of ego identities have stands for continuity and coherence. "The feeling of self-identity is the accumulated confidence that the unity and continuity that we have in the eyes of others, a capacity equivalent to maintain internal consistency and continuity."
"The conscious feeling of having a personal identity is based on two simultaneous observations: the immediate perception of one's sameness and continuity in time, and recognizes the related perception about such equality and continuity (Erikson, 1950). What we propose to call is ego-identity, that means more than the mere fact of existence, mediated by personal identity, it is the ego quality of this existence. So identity is under this subjective aspect of becoming aware of the fact that in the synthesizing method of the self is an equality and continuity prevails, and that these methods are effective to ensure their own equality and continuity in the eyes of others. Erikson has developed a stage theory of psychosocial development, because in his eyes and identity management arises precisely because of the development tasks. ...