 Freud’s metapsychology of the libidinal economy, of the underlying motivational mechanisms of psychical life, is grounded on his theory of drive (Trieb, and not Instinkt, despite many English mistranslations of Trieb as “instinct”). Lacan elaborates upon and extends this Freudian theoretical framework. In the process, he reworks some of Freud’s concepts and adds other concepts of his own.