Noun | 1. | pleasure-unpleasure principle - (psychoanalysis) the governing principle of the id; the principle that an infant seeks gratification and fails to distinguish fantasy from reality depth psychology, psychoanalysis, analysis - a set of techniques for exploring underlying motives and a method of treating various mental disorders; based on the theories of Sigmund Freud; "his physician recommended psychoanalysis" principle - a basic truth or law or assumption; "the principles of democracy" |