To enter into and study the “external world,” psychoanalysis simply extends the principle of psychic or determinism into another realm of human experience. 
 

Just as human beings produce symptomatic acts and slips-of-the-tongue as an expression of unconscious forces, so are these forces and fantasies expressed in the external world, shaping ideas and ideologies, and structuring behavior in culture.

The first phase of the Freudian revolution was recognition that the psychic life and behavior of individual human beings is motivated by forces of which we are not aware.

The next phase of the Freudian revolution (that is in the process of coming into being) is recognition that entire societies are driven by forces of which human beings are not aware.

Entering the external world, psychoanalysis interprets fantasies enacted by the human race. Norman O. Brown states that psychoanalysis fulfills itself “only when it becomes historical and cultural analysis.” This task of cultural and historical interpretation may be described as the project of "making conscious the unconscious on the stage of social reality."  

Psychoanalysis expands the scope of its mission by focusing not only on events occurring within the clinical situation, but also upon events occurring outside the clinical situation—in social reality. Freud called dreams the “royal road to the (individual) unconscious.” I view political ideology as the royal road to the cultural unconscious.