His ideas quickly solidified into doctrine and became, with the early essays of I. A. Richards, the basis of the most influential school of literary criticism in this century, the so-called New Criticism. Three of these essays--"Tradition and the Individual Talent," "Hamlet and His Problems," and "The Metaphysical Poets"--outline in canonical form such modern critical doctrines as "tradition," "impersonality," "irrelevancy of belief," "objective correlative," and "unified sensibility."
Through half a century of critical writing, Eliot's concerns remained more or less constant; his position regarding those concerns, however, was frequently refined, revised, or, occasionally, reversed. He discovered, though, that those early and tentative formulations had taken on a life of their own. Even today, most commentators seem to be unaware of the complexity of Eliot's developing critical mind and of the distortion which results from the assumption that those well-known phrases do justice to that mind. Beginning in the late 1920s. Eliot's literary criticism was supplemented by, at times supplanted by, religious and social criticism. Some of these writings, such as The Idea of a Christian Society (1939), are interesting as social commentary and elucidative in regard to his plays and to Four Quartets.