<P> The concepts themselves arose at a late stage in the development of Freud's thought as the "structural model" (which succeeded his "economic model" and "topographical model") and was first discussed in his 1920 essay Beyond the Pleasure Principle and was formalized and elaborated upon three years later in his The Ego and the Id . Freud's proposal was influenced by the ambiguity of the term "unconscious" and its many conflicting uses . </P> <P> The id (Latin for "it", German: Es) is the disorganized part of the personality structure that contains a human's basic, instinctual drives . Id is the only component of personality that is present from birth . It is the source of our bodily needs, wants, desires, and impulses, particularly our sexual and aggressive drives . The id contains the libido, which is the primary source of instinctual force that is unresponsive to the demands of reality . The id acts according to the "pleasure principle"--the psychic force that motivates the tendency to seek immediate gratification of any impulse--defined as seeking to avoid pain or unpleasure (not "displeasure") aroused by increases in instinctual tension . According to Freud the id is unconscious by definition: </P> <P> It is the dark, inaccessible part of our personality, what little we know of it we have learned from our study of the dreamwork and of course the construction of neurotic symptoms, and most of that is of a negative character and can be described only as a contrast to the ego . We approach the id with analogies: we call it a chaos, a cauldron full of seething excitations...It is filled with energy reaching it from the instincts, but it has no organization, produces no collective will, but only a striving to bring about the satisfaction of the instinctual needs subject to the observance of the pleasure principle . </P> <P> In the id: </P>

Where are the id ego and superego located