Erikson's stages of psychosocial development, as articulated in the second half of the 20th century by Erik Erikson in collaboration with Joan Erikson, is a comprehensive psychoanalytic theory that identifies a series of eight stages that a healthy developing individual should pass through from infancy to late adulthood. According to Erikson’s theory the results from each stage, whether positive or negative, influences the results of succeeding stages. Erikson published a book called "Childhood and Society" around the 1950’s that made his research well known on the eight stages of psychosocial development. Erikson was originally influenced by Sigmund Freud’s psychosexual stages of development. He began by working with Freuds theories specifically. However, as he began to dive deeper into biopsychosocial development and how other environmental factors affect human development, he soon progressed past Freud’s theories and developed his own ideas.