In this book, Martha Rust advances a new theory of what written lists are and how they work, arguing that they signify not only as collections of words but also as series of images and things. As a consequence, lists call upon mental skills associated not only with literacy but also with numeracy, competencies that verge upon each other in the semantic field of the word "reckoning": tallying, telling, counting, ordering, categorizing, and rendering account-whether with respect to affairs of the world or to the soul. Rust develops this theory of the list form in the context of late medieval English lists of sevens, lists of relics, lists of times (in the form of schedules), and lists of place names (in the form of itineraries). When taken as the material for poems or diagrams, these lists engage readers and viewers in interactive reckonings with the multi-modal potentials of the list form. Inevitably, Middle English examples of this poetics of reckoning open onto matters that are beyond reckoning. Although it focuses on medieval lists, this book will appeal to readers interested in the cognitive turn in literary criticism as well as to lovers of lists more generally.