This book is the first full-scale account of the growth of Wordsworth’s thinking about the theory of poetry. It draws mainly on his formal critical essays but also on unpublished material and personal statements about poetics and the growth and constitution of the poet’s mind in The Prelude, in other verse, and in letters. The foundation of the discussion is an account of the Preface to Lyrical Ballads, based on Professor Owen’s edition of that text published in 1957. The chapters on the Essays upon Epitaphs, the Preface or 1815, and the Essay, Supplementary to the Preface, trace a process of development in which the critic silently abandons the more embarrassingly controversial elements of his earliest argument (such as his advocacy of the language of rustics and the language of prose), confirms its more satisfactory features, and progresses to a subtle, intricate, and rewarding account of his psychology of literary creation and of the audience’s reaction to literature. This study reveals, on the one hand, Wordsworth’s familiarity with the general drift of eighteenth-century of theorizing on aesthetics, especially as it dealt with the concepts of primitivism and of the sublime; and on the other, his increasing grasp of a psychological definition of the poet’s making, and the reader’s reception of literature such as is more usually associated with Coleridge. Professor Owen’s understanding of the documents and his wide knowledge of the background of the theories emerge in this important contribution to Romantic Studies.