literary criticism, Discipline concerned with philosophical, descriptive, and evaluative inquiries about literature, including what literature is, what it does, and what it is worth. The Western critical tradition began with Plato’s Republic (4th century bce). A generation later, Aristotle, in his Poetics, developed a set of principles of composition that had a lasting influence. European criticism since the Renaissance has primarily focused on the moral worth of literature and the nature of its relationship to reality. At the end of the 16th century, Sir Philip Sidney argued that it is the special property of literature to offer an imagined world that is in some respects superior to the real one. A century later John Dryden proposed the less idealistic view that literature must primarily offer an accurate representation of the world for “the delight and instruction of mankind,” an assumption that underlies the great critical works of Alexander Pope and Samuel Johnson. A departure from these ideas appeared in the criticism of the Romantic period, epitomized by William Wordsworth’s assertion that the object of poetry is “truth…carried alive into the heart by passion.” The later 19th century saw two divergent developments: an aesthetic theory of “art for art’s sake,” and the view (expressed by Matthew Arnold) that literature must assume the moral and philosophical functions previously filled by religion. The volume of literary criticism increased greatly in the 20th century, and its later years saw a radical reappraisal of traditional critical modes and the development of a multiplicity of critical factions (see deconstruction; poststructuralism; structuralism).