In Group Psychology and the Analysis of the Ego, (1922), Sigmund Freud based his preliminary description of group psychology on Le Bon's work, but went on to develop his own, original theory, related to what he had begun to elaborate in Totem and Taboo. Theodor Adorno reprised Freud's essay in 1951 with his Freudian Theory and the Pattern of Fascist Propaganda, and said that "It is not an overstatement if we say that Freud, though he was hardly interested in the political phase of the problem...

In his later work, Freud proposed that the human psyche could be divided into three parts: Id, ego and super-ego. Freud discussed this model in the 1920 essay Beyond the Pleasure Principle, and fully elaborated upon it in The Ego and the Id (1923), in which he developed it as an alternative to his previous topographic schema (i.e., conscious, unconscious and preconscious).

The id is the completely unconscious, impulsive, childlike portion of the psyche that operates on the "pleasure principle...