This anthology of texts in translation, here presented in a fully revised and updated form, covers the single most important branch of medieval literary theory and criticism, the commentary tradition, in one of the most significant periods of its development. The majority of the texts are here translated for the first time; most of the translations have been prepared specially for this edition. They offer discussion of such topics as fiction and fable (in classical poetry and in the Bible); the ethical effects and purpose of literature; authorship and authority; the function of biography in literary interpretation; stylistic and didactic modes of writing; literary form and structure; allegory and literal-historical sense; symbolism; imagination and imagery; the semiotics of words and things, the moralization of classical texts; the status of poetry within the hierarchy of the human arts and sciences; and the prestige and purpose of vernacular literature. The selections are fully annotated and provided with introductions which form a linked series of essays towards the history of medieval literary theory and criticism.