The most important theme in The Interpretation of Dreams is Freud's concept of the unconscious versus the conscious mind. As the title indicates, Freud argues that the workings of the unconscious are accessible through dream interpretation. In particular, Freud thought that dreams revealed events from one's childhood, often including desires and wishes that were unfulfilled. People's conscious minds "censored" these desires, which were inappropriate or socially unacceptable. "Censorship," another important theme, was necessary to live a normal life, but it also disguised the deepest desires of an individual, the repression of which Freud thought could also lead to mental illness. Finally another crucial theme was that the interpretation of dreams could be used in an attempt to uncover the sources of psychological problems. The Interpretation of Dreams is not only a revolutionary treatise on the workings of the human mind, but also a manifesto for the use of psychoanalysis to treat mental illness, the origins of which were revealed in dreams.