Historically, depth psychology (from the German term Tiefenpsychologie), was coined by Eugen Bleuler to refer to psychoanalytic approaches to therapy and research which take the unconscious into account. The term was rapidly accepted in the year of its proposal (1914) by Sigmund Freud, to cover a topographical view of the mind in terms of different psychic systems.
Depth psychology has since come to refer to the ongoing development of theories and therapies pioneered by Pierre Janet, William James, and Carl Jung as well as Freud, which explore the relationship between the conscious and the unconscious (thus including both psychoanalysis and Jungian psychology).
Depth psychology states that psyche is a process that is partly conscious and partly unconscious and partly semi-conscious. In practice, depth psychology seeks to explore underlying motives as an approach to various mental disorders, with the belief that the uncovering of these motives is intrinsically healing. It seeks the deep layers underlying behavioral and cognitive processes. The initial work and development of the theories and therapies by Sigmund Freud, Carl Jung, Alfred Adler and Otto Rank have resulted in three main perspectives on depth psychology in modern times:
Ken Wilbur Integral Psychology (2000)