In psychoanalysis and other psychological theories, the unconscious mind (or the unconscious) is the part of the psyche that is not available to introspection. Although these processes exist beneath the surface of conscious awareness, they are thought to exert an effect on conscious thought processes and behavior. The term was coined by the 18th-century German Romantic philosopher Friedrich Schelling and later introduced into English by the poet and essayist Samuel Taylor Coleridge.

The emergence of the concept of the unconscious in psychology and general culture was mainly due to the work of Austrian neurologist and psychoanalyst Sigmund Freud. In psychoanalytic theory, the unconscious mind consists of ideas and drives that have been subject to the mechanism of repression: anxiety-producing impulses in childhood are barred from consciousness, but do not cease to exist, and exert a constant pressure in the direction of consciousness. However, the content of the unconscious is only knowable to consciousness through its representation in a disguised or distorted form, by way of dreams and neurotic symptoms, as well as in slips of the tongue and jokes. The psychoanalyst seeks to interpret these conscious manifestations in order to understand the nature of the repressed.

The unconscious mind can be seen as the source of dreams and automatic thoughts (those that appear without any apparent cause), the repository of forgotten memories (that may still be accessible to consciousness at some later time), and the locus of implicit knowledge (the things that we have learned so well that we do them without thinking). Phenomena related to semi-consciousness include awakening, implicit memory, subliminal messages, trances, hypnagogia and hypnosis. While sleep, sleepwalking, dreaming, delirium and comas may signal the presence of unconscious processes, these processes are seen as symptoms rather than the unconscious mind itself.

Some critics have doubted the existence of the unconscious altogether.

Historical overview German The term "unconscious" () was coined by the 18th-century German Romantic philosopher Friedrich Schelling (in his System of Transcendental Idealism, ch. 6, § 3) and later introduced into English by the poet and essayist Samuel Taylor Coleridge (in his Biographia Literaria).Murray, Christopher John. Encyclopedia of the Romantic Era, 1760-1850. Taylor & Francis, 2004: , pp. 1001–1002. Some rare earlier instances of the term "unconsciousness" () can be found in the work of the 18th-century German physician and philosopher Ernst Platner.Platner, Ernst. Philosophische Aphorismen nebst einigen Anleitungen zur philosophischen Geschichte, Vol. 1 (Leipzig: Schwickertscher Verlag, 1793 ), p. 86.Nicholls, Angus and Martin Liebscher (2010). Thinking the Unconscious: Nineteenth-Century German Thought. Cambridge University Press, p. 9.

Vedas Influences on thinking that originate from outside an individual's consciousness were reflected in the ancient ideas of temptation, divine inspiration, and the predominant role of the gods in affecting motives and actions. The idea of internalised unconscious processes in the mind was present in antiquity, and has been explored across a wide variety of cultures. Unconscious aspects of mentality were referred to between 2,500 and 600 BC in the Hindu texts known as the Vedas, found today in Ayurvedic medicine.Alexander, C. N. (1990). "Growth of Higher Stages of Consciousness: Maharishi's Vedic Psychology of Human Development". C. N. Alexander and E. J. Langer (eds.). Higher Stages of Human Development. Perspectives on Human Growth. New York, Oxford: Oxford University Press.

Paracelsus Paracelsus is credited as the first to make mention of an unconscious aspect of cognition in his work Von den Krankheiten (translates as "About illnesses", 1567), and his clinical methodology created a cogent system that is regarded by some as the beginning of modern scientific psychology.Harms, Ernest., Origins of Modern Psychiatry, Thomas 1967 ASIN: B000NR852U, p. 20.

Shakespeare William Shakespeare explored the role of the unconsciousThe Design Within: Psychoanalytic Approaches to Shakespeare: Edited by M. D. Faber. New York: Science House. 1970 An anthology of 33 papers on Shakespearean plays by psychoanalysts and literary critics whose work has been influenced by psychoanalysis. in many of his plays, without naming it as such.Meyer-Dinkgräfe, Daniel "Hamlet's Procrastination: A Parallel to the Bhagavad-Gita, in Hamlet East West, edited by. Marta Gibinska and Jerzy Limon. Gdansk: Theatrum Gedanese Foundation, 1998e, pp. 187–195.Meyer-Dinkgräfe, Daniel 'Consciousness and the Actor: A Reassessment of Western and Indian Approaches to the Actor's Emotional Involvement from the Perspective of Vedic Psychology.' Frankfurt am Main: Peter Lang, 1996a. (Series 30: Theatre, Film and Television, Vol. 67).

Philosophy In his work Anthropology from a Pragmatic Point of View, philosopher Immanuel Kant was one of the first to discuss the subject of unconscious ideas.

Western philosophers such as Arthur Schopenhauer,Ellenberger, H. (1970) The Discovery of the Unconscious: The History and Evolution of Dynamic Psychiatry New York: Basic Books, p. 542.Young, Christopher and Brook, Andrew (1994) Schopenhauer and Freud quotation: Baruch Spinoza, Gottfried Wilhelm Leibniz, Johann Gottlieb Fichte, Georg Wilhelm Friedrich Hegel, Karl Robert Eduard von Hartmann, Carl Gustav Carus, Søren Aabye Kierkegaard, Friedrich Wilhelm NietzscheFriedrich Nietzsche, Preface to the second edition of "The Gay Science" 1886. and Thomas Carlyle used the word unconscious.

In 1880 at the University of Paris, Edmond Colsenet defended a philosophy thesis (PhD) on the unconscious."Un débat sur l'inconscient avant Freud: la réception de Eduard von Hartmann chez les psychologues et philosophes français". de Serge Nicolas et Laurent Fedi, L'Harmattan, 2008, p. 8. Élie Rabier and Alfred Fouillée performed syntheses of the unconscious "at a time when Freud was not interested in the concept"."Un débat sur l'inconscient avant Freud: la réception de Eduard von Hartmann chez les psychologues et philosophes français". de Serge Nicolas et Laurent Fedi, L'Harmattan, Paris, 2008, p. 8.

Psychology

Nineteenth century

According to historian of psychology Mark Altschule, "It is difficult—or perhaps impossible—to find a nineteenth-century psychologist or psychiatrist who did not recognize unconscious cerebration as not only real but of the highest importance."Altschule, Mark. Origins of Concepts in Human Behavior. New York: Wiley, 1977, p.199 In 1890, when psychoanalysis was still unheard of, William James, in his monumental treatise on psychology (The Principles of Psychology), examined the way Schopenhauer, von Hartmann, Janet, Binet and others had used the term 'unconscious' and 'subconscious.'"Meyer, Catherine (edited by). Le livre noir de la psychanalyse: Vivre, penser et aller mieux sans Freud. Paris: Les Arènes, 2005, p.217 German psychologists, Gustav Fechner and Wilhelm Wundt, had begun to use the term in their experimental psychology, in the context of manifold, jumbled sense data that the mind organizes at an unconscious level before revealing it as a cogent totality in conscious form."Wozniak, Robert H. Mind and Body: Rene Déscartes to William James. Washington DC: American Psychological Association, 1992 Eduard von Hartmann published a book dedicated to the topic, Philosophy of the Unconscious, in 1869.

Freud

Sigmund Freud and his followers developed an account of the unconscious mind. He worked with the unconscious mind to develop an explanation for mental illness.Freud, S. (1940). An outline of psycho-analysis. The International Journal of Psychoanalysis, 21, 27–84.

For Freud, the unconscious is not merely that which is not conscious. He refers to that as the descriptive unconscious and it is only the starting postulate for real investigation into the psyche. He further distinguishes the unconscious from the pre-conscious: the pre-conscious is merely latent – thoughts, memories, etc. that are not present to consciousness but are capable of becoming so; the unconscious consists of psychic material that is made completely inaccessible to consciousness by the act of repression. The distinctions and inter-relationships between these three regions of the psyche—the conscious, the pre-conscious, and the unconscious—form what Freud calls the topographical model of the psyche. He later sought to respond to the perceived ambiguity of the term "unconscious" by developing what he called the structural model of the psyche, in which unconscious processes were described in terms of the id and the superego in their relation to the ego.

In the psychoanalytic view, unconscious mental processes can only be recognized through analysis of their effects in consciousness. Unconscious thoughts are not directly accessible to ordinary introspection, but they are capable of partially evading the censorship mechanism of repression in a disguised form, manifesting, for example, as dream elements or neurotic symptoms. Such symptoms are supposed to be capable of being "interpreted" during psychoanalysis, with the help of methods such as free association, dream analysis, and analysis of verbal slips and other unintentional manifestations in conscious life.

Jung

Carl Gustav Jung agreed with Freud that the unconscious is a determinant of personality, but he proposed that the unconscious be divided into two layers: the personal unconscious and the collective unconscious. The personal unconscious is a reservoir of material that was once conscious but has been forgotten or suppressed, much like Freud's notion. The collective unconscious, however, is the deepest level of the psyche, containing the accumulation of inherited psychic structures and archetypal experiences. Archetypes are not memories but energy centers or psychological functions that are apparent in the culture's use of symbols. The collective unconscious is therefore said to be inherited and to contain material of an entire species rather than of an individual."collective unconscious (psychology) -- Britannica Online Encyclopedia." Encyclopedia - Britannica Online Encyclopedia. N.p., n.d. Web. 4 Dec. 2011. <http://www.britannica.com/EBchecked/topic/125572/collective-unconscious>. The collective unconscious is, according to Jung, "[the] whole spiritual heritage of mankind's evolution, born anew in the brain structure of every individual".Campbell, J. (1971). Hero with a thousand faces. New York, NY: Harcourt Brace Jovanovich

In addition to the structure of the unconscious, Jung differed from Freud in that he did not believe that sexuality was at the base of all unconscious thoughts."Jung, Carl Gustav." The Columbia encyclopedia. 6th. ed. Columbia: Columbia University Press, 2000. 1490. Print.

Dreams

Freud The purpose of dreams, according to Freud, is to fulfill repressed wishes while simultaneously allowing the dreamer to remain asleep. The dream is a disguised fulfillment of the wish because the unconscious desire in its raw form would disturb the sleeper and can only avoid censorship by associating itself with elements that are not subject to repression. Thus, Freud distinguished between the manifest content and latent content of the dream. The manifest content consists of the plot and elements of a dream as they appear to consciousness, particularly upon waking, as the dream is recalled. The latent content refers to the hidden or disguised meaning of the events and elements of the dream. It represents the unconscious psychic realities of the dreamer's current issues and childhood conflicts, the nature of which the analyst is seeking to understand through interpretation of the manifest content.