Literary theory is the development of ideas and methods used in the practical reading of fiction, which can reveal the underlying themes and meanings of the text. It is defined as the principles or tools which can be used to understand literature. Literary theory formulates the relationship between author and work, and develops the significance of race, class, and gender for literary study, both from the standpoint of the biography of the author and an analysis of their themes present in the text. It can also be used to understand the role of historical context in interpretation as well as the relevance of linguistic and unconscious elements of the text, and explaining the degree to which the text is the product of a culture as much as an individual author, and vice versa.
There are several types of literary theory. These include contextualism, a school of thought focusing on the work as an autonomous entity. There is also textual criticism, which is the close study of a work in order to establish its original text, which may have been altered over time. Theoretical criticism is the critical approach or doctrine used to examine a work in the light of certain theories of literature, or uses the text as a support for the development of literary theory. Platonic criticism is an approach analysing the external value of a work, its non-artistic usefulness and historical context. Aristotelian criticism applies a formal, logical approach to literary analysis. Practical criticism is the analysis of the text itself and is a popular approach throughout mainstream education.
Chris Baldick, a professor of English at Goldsmiths' College, University of London, analyzed the social functions of criticism and broadly categorized critics into three groups: the poet-critics (like Whitman, James, Eliot, Pound, and Lawrence), the men of letters (like Carlyle, Emerson, Woolf, and Middleton Murry), and the academic critics (like Saintsbury, Bradley, Richards, Leavis, and Knight) in his book Criticism and Literary Theory 1890 to the Present. He also concluded from the 1890s to the 1990s the study of literary theory underwent many changes. From 1890 to 1918, it dealt with the descent from decadent estheticism to treating concepts like omniscience, modernism, and realism. The period of 1918 to 1945 marked the beginning of the modernist revolution with the wave of New Criticism started by T. S. Eliot. From 1945 to 1968, the examination of various literary tendencies and alternatives to New Criticism emerged as a popular way to study literary theory. Then, from 1968 to the 1990s, literary theory dealt with the implications of textual politics.
Hazard Adams' Critical Theory Since Plato (1971) described the rather formless mass of critical theory as a four-fold idea which can be classified as containing the following ideas. The first idea focused on the ‘nature of being and existence' in writing and how that related to literary theory. He also examined the linguistic approaches in literary theory, which means looking at the emphasis on the language in the work. Adams also addressed the issue of political or cultural criticism of literary work and before lastly examining the limitations of knowledge (which is known as Epistemology). This encompasses the theories focusing on the study of how we come to know what we know.
His study was based on the theories of Meyer Abrams as published in The Mirror and the Lamp in 1953. In this work, Abrams also classified literary theory as being four-fold: He explored the themes of mimetic theory, the assumption art is an imitation of nature. He also discussed the pragmatic theory which focuses on the practical value of what a work of art should do for the reader. Abrams also looked at expressive theory, which is the viewing of art as the product of an inner creative process, and the objectivist theory, which is the isolation of work from its socio-cultural meaning and purely concentrating on the language used in the text. However, both Abrams and Adams acknowledged these approaches have the tendency to recycle themselves endlessly, and Adams stated a "case can be made that the history of critical theory is one of cyclical error."