whether one agrees with Freud's conclusions or adopts the view that any of a variety of biases and emerging neuroscience research into the brain weaken his theories of the mind (e.g., Leland, 1995), Freud, the founder of the psychoanalytic discipline, is difficult to trivialize and even more difficult to overlook. This is an important point because Freud's personality theory is laden with terminology that may seem familiar but that reaches and retains technical clinical meanings that are fundamental to and that inform virtually all subsequent personality theory.
Freud arrives at the structural hypothesis, also called structural theory (Boesky, 1995), in The Interpretation of Dreams (first published in 1900) and further develops his views, not only in The Ego and the Id (1923) but also in multiple commentaries on a whole range of human experience; as a group, these commentaries appear intended to reinforce the validity of the original hypothesis. Freud cites the conceptual leap he made from working with hysterical patients to describing "normal" psychology by way of dreams, which are characterized by unconscious, nonvolitional mental processes and narrative and mental disarray, much in the manner of the skewed psychological state of hysterics. He justifies that leap based on "the discovery that the dreams and mistakes ('parapraxes,' such as slips of the tongue, etc.) of normal men have the same mechanism as neurotic symptoms" (Freud, 2000).
Freud describes three states of being: preconscious (Pcs), unconscious (Ucs), and conscious (Cs). The unconscious processes of the mind, which are highly complex, are identified in general terms as the locus of personality control. The Ucs is the source of "the impetus to dream formation" (Freud, 1978, p. 397), and decoding dreams is a mechanism of decoding the Ucs itself. The role of the Ucs is decisive for Freud, who describes psychoanalysis, as "the science of unconscious mental processes, wh...