German psychoanalyst Erik H. Erikson contributed greatly to the field of psychology with his theories on child development, which organized the sequence of development into eight distinct stages. This theory does not boil down to a single “aha” moment in Erikson's life; instead, its origins lie in the personal influence of Erikson's own experiences and the inspiration he took from other prominent psychoanalysts of his time.

An Identity Crisis

Erikson's theories revolve around the development of identity and were integral to the popular notion of the “identity crisis” as explored in his 1968 book, “Identity: Youth and Crisis.” His own life likely served as inspiration for this theory; he was born as Erik Homberger in Germany to an unknown Danish father, and -- though he looked distinctly Nordic -- was raised by a Jewish mother. As a child, he was teased for being both Nordic and Jewish, and as a wandering youth he aspired to become an artist. The advent of World War II forced Erikson and his wife to flee numerous times, until they eventually ended up in Boston, where he changed his name. In his personal experience, Erikson's identity was constantly evolving, just as his theories teach ongoing identity development.

Following Freud

Erikson kept company with numerous anthropologists, including Gregory Bateson, Ruth Benedict and Margaret Mead. He took inspiration from his colleagues, but none influenced him so greatly as Sigmund Freud. Erikson's theories have a Freudian core, but they expand on Freud's concepts. While Freud presents five stages of development ending at adolescence, Erikson presents eight. Freud focuses heavily on childhood forming the basis of identity, whereas Erikson teaches that development continues to change and evolve throughout a person's entire lifespan, reaching well into late adulthood.

In the Field

Prior to the publication of his first book, 1950's “Childhood and Society,” Erikson spent time among Native American peoples, such as the Oglala Lakota. There, he learned of the concept of the dream quest -- a young boy's grueling coming-of-age hunting journey -- and witnessed the tribe losing their traditional identity to modern white customs. These experiences, which illustrate the effect of culture on personality, strongly informed Erikson's theories; he summarizes them in “Childhood,” which lays the basic groundwork for his developmental theories.

Life Influences Theory

Erik Erikson lived until 1994 and continued to publish throughout his life, presenting expansions of his childhood development theories as well as new psychoanalytic ideas. As he did with the Lakota, Erikson continued to look to real-world experiences to shape his theories. In his work at institutions including Yale, Berkeley, Harvard and Mount Zion Hospital, he reported on experiences with child-rearing practices among the Sioux and Yurok, the play activities of disturbed and healthy children and social behavior in India, among other subjects, and these experiences continued to inform his writings.