Psychosis is one of three clinical structures. The others are neurosis and perversion. Psychosis is distinctly different from both through the mechanism of rejection, while neurosis is characterized by compulsion and perversion by denial. Through the rejection of an "original signifier," the psychotic loses control over language. Here, Lacan develops his theory of language, which includes the concepts of metonymy and metaphor, as well as the theory of stepping points, the special signifiers at which, under normal circumstances, language and things, signifiers and signifieds are linked, so that the psychotic sliding can be halted.