This is the first complete English translation of On the Purity of the Art of Logic, a handbook of logic written in Latin by English philosopher Walter Burley (c. 1275-1344/5). The work circulated in the Middle Ages in two versions, a shorter and a longer one, both translated here by Paul Vincent Spade. The translations arc based on the only complete edition of Burley's treatises, corrected by Spade on the basis of one of the surviving manuscripts. The book also includes an extensive introduction, explanatory notes, a table of corresponding passages between the two versions, a select annotated bibliography, and three indexes.

A contemporary of John Duns Scotus and William of Ockham, Burley was active at the universities of both Paris and Oxford. He became one of the most important figures in the transformation of medieval logic and semantics that took place in the early fourteenth century. Burley used new tools and techniques of logical and semantical analysis, yet in many cases he used them in defense of traditional views, such as a realist metaphysical theory of "universals". On the Purity of the Art of Logic shows both these sides of Burley -- the innovator and the conservative -- as well as some of the ways in which his views corresponded or clashed with those of William of Ockham.

The Franciscan William of Ockham was an English medieval philosopher, theologian, and political theorist. Ockham is important not only in the history of philosophy and theology, but also in the development of early modern science and of modern notions of property rights and church-state relations. This volume offers a full discussion of all significant aspects of Ockham's thought: logic, philosophy of language, metaphysics and natural philosophy, epistemology, ethics, action theory, political thought and theology. It is the first study of Ockham in any language to make full use of the new critical editions of his works, and to consider recent discoveries concerning his life, education, and influences.

'This sentence is false' - is that true? The 'Liar paradox' embodied in those words exerted a particular fascination on the logicians of the Western later Middle Ages, and, along with similar 'insoluble' problems, forms the subject of the first group of articles in this volume. In the following parts Professor Spade turns to medieval semantic theory, views on the relationship between language and thought, and to a study of one particular genre of disputation, that known as 'obligationes'. The focus is on the Oxford scholastics of the first half of the 14th century, and it is the name of William of Ockham which dominates these pages - a thinker with whom Professor Spade finds himself in considerable philosophical sympathy, and whose work on logic and semantic theory has a depth and richness that have not always been sufficiently appreciated.

The Franciscan William of Ockham was an English medieval philosopher, theologian, and political theorist. Ockham is important not only in the history of philosophy and theology, but also in the development of early modern science and of modern notions of property rights and church-state relations. This volume offers a full discussion of all significant aspects of Ockham's thought: logic, philosophy of language, metaphysics and natural philosophy, epistemology, ethics, action theory, political thought and theology. It is the first study of Ockham in any language to make full use of the new critical editions of his works, and to consider recent discoveries concerning his life, education, and influences.