Melanie Klein has described the earliest stages of infantile psychic life in terms of a successful completion of development through certain "positions". A position, for Klein, is a set of psychic functions that correspond to a given phase of development, always appearing during the first year of life, but which are present at all times thereafter and can be reactivated at any time. There are two major positions: the paranoid-schizoid position and the subsequent depressive position. The earlier more primitive position is the paranoid-schizoid position and if an individual's environment and up-bringing are satisfactory, she or he will progress through the depressive position.