Scholars have known that a variety of medieval theories on relation existed, but no full-length systematic study has been attempted until now. With this book Henninger fills an important gap in our knowledge of medieval philosophy. Dealing with such varied thinkers as Aquinas, Henry of Ghent, Richard of Mediavilla, John Duns Scotus, Henry of Harclay, William of Ockham, and Peter Aureoli, the book will interest anyone concerned with late medieval philosophy and the transition to the early modern period.