Critics and their fancy interpretive fashions may come and go, but literary works remain changeless and pristine, untouched by the vagaries and excesses of critical theory. Criticism in the form of source study helps us fill in the background to Chaucer's poetry; the study of the manuscripts in which his work appears helps to illuminate the contexts of textual production, circulation and contemporary reception of his work. For literary critics and theorists, the fact that different generations of critics have found different things to admire in Chaucer's poetry is testimony not to our own inconsistencies or failures, but rather to the welcome and lively sense that our relationship to the past is dynamic and, at best, interrogative and critical. Chaucer himself seems often to refuse to make a determination, though he appears comfortable enough rehearsing other people's opinions and deferring judgment.