Reasons for the Discourse Transformation of Western Literary Theories in the 20th Century

In the 20th century,western literary theories flourished and the collision,blend and transformation of pluralistic literary theories became the developing trend of western literary theories.This paper sorts out the sequence of western literary theories in the 20th century and analyzes the effects of social development and changes,trend of thought in philosophy and aesthetics,linguistics and philosophy of language on the evolution of literary theories so that we can use the meaningful component parts in evolution for reference to develop and enrich Chinese literary theories.