The Bedford Glossary of Critical and Literary Terms - Ross Murfin 2018
Theoretical criticism: A type of literary criticism that emphasizes the formulation of general principles for all texts rather than the explication of individual works, as in practical criticism. Theoretical critics postulate a set of aesthetic principles that can be used to analyze and evaluate literary works in general. Aristotle’s Poetics (c. 330 B.C.) is perhaps the best-known example of theoretical criticism; other noted examples include I. A. Richards’s Principles of Literary Criticism (1924) and Wayne Booth’s The Rhetoric of Fiction (1961).
American critics by and large engaged in practical rather than theoretical criticism during the first half of the twentieth century. However, with the advent of the Chicago school, which emphasized theory and method, theoretical criticism came into vogue. Theoretical criticism has since been written by practitioners of approaches ranging from formalism and structuralism to cultural criticism, feminist criticism, the new historicism, and queer theory. Poststructuralists in particular have placed a premium on theory, insisting that critics theorize their critical practices.