Psychoanalysis, as formulated by its developer, Dr. Sigmund Freud, is a treatment of psychological disorder and treatments. It is based on the assumption that the majority of mental activity is unconscious. And, as such, understanding the workings of the mind requires uncovering the unconscious meaning behind or influencing their behavior. Tools in this search for understanding and clarity include looking at repressed impulses, internalized conflicts and early traumas experienced by the individual. Several concepts are assumed in this search: infantile sexuality, the Oedipus complex, instincts, the pleasure and reality principles , the distinction between id, ego and superego and finally, the anxiety and defense mechanism. Analysis is directed primarily at the composition of psychoneuroses which, the theory states, can be brought about by modification of and in the personality.