Freud distinguishes between conscious, unconscious and preconscious systems (designated as Cs., Ucs., and Pcs.). The preconscious is really a sub-division of consciousness but cannot be classified along with consciousness because it consists largely of memory, including things we do without thinking about them, such as walking and driving a car. Something you actually have in your mind now obviously is conscious. Something you know but are not actually thinking about has to be somewhere else, where you can get hold of it when you want—the preconscious. Ideas from the preconscious can slip into the unconscious, though unconscious thoughts can only enter the preconscious if subject to the usual censorship. For example, if you can’t remember the name of someone you know, it has temporarily slipped from the preconscious into the unconscious.
Already, in his 1896 letters to Wilhelm Fleiss ("Extracts from the Fliess Papers," 1950a), Freud connected the pre-conscious associated with verbal representations as being the ego. The full definition of the preconscious emerged only within the delineation of the first topographical theory, although it was never precisely formulated. The preconscious (Pcs.) can only be conceived in opposition to the unconscious (Ucs.): It is the very differentiation between the two that makes it possible to think of a topography of the...
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- Muller, John P. and William J. Richardson. Lacan and Language: A Reader's Guide to Ecrits. New York: International Universiites Press, Inc., 1982.