Although psychological approaches to literature have been encouraged by Freud's psychoanalytic theory, they have always existed. Aristotle's description of the catharsis (literally "purification") of human emotions that a tragedy causes in the audiences is a classic example. Romantic authors such as Coleridge and Shelley revealed, decades before Freud's work, an interest for the workings of the unconscious and how this influences literary imagination.
Freud's most revolutionary and influential argument was that a large part of the human mind, where all the subjects' experiences are stored in layers upon layers, is not directly under the individuals' control. This part forms the unconscious and, because it emerges through linguistic expressions, the concept has a clear relevance for literary production and imagination. According to Freud, language has a double structure: we assume that we know what we are communicating, but actually there is always something else that we are communicating of which we are not completely aware. Thus, psychoanalytic criticism uses the tecnique of the close readings of texts to unconver hidden, unconscious meanings.
In the 1960s, the combination of psychoanalysis and structuralism has given rise to a series of studies that interrogate how literature relates to power, and, from a feminist point of view, to patriarchy. These studies were stimulated by Jacques Lacan's insights that language structures the individual and that the subject's emergence from undifferentiation (the mirror phase) represents the acquisition of language and the concurrent submission to social authority.