Introduction

Ockham's Summa logicae (The Logic Handbook), written c. 1323, is a manifesto masquerading as a textbook. Its aim, Ockham disingenuously declares in his Preface, is merely to help beginning students in theology avoid elementary difficulties in logic. His undeclared aim is far more ambitious. In the Summa logicae Ockham puts forward a new philosophical programme designed to supersede the views of his contemporaries and predecessors, views that come in for extensive and trenchant criticism in the course of its many pages. We call that programme and the movement it engendered “nominalism”. Its guiding principle is the conviction that only concrete individuals exist, and hence that any other purported entities are no more than names (nomina), traditionally expressed as the maxim not to multiply entities beyond necessity, a formulation known as “Ockham's razor”. This principle has a wide range of application, and it has deep theological as well as philosophical consequences. The Summa logicae lays out in systematic detail Ockham's account of logic and language, providing him with the necessary groundwork for applying his razor.

Ockham's goal in the Summa logicae, then, is to expound and promote his nominalist programme in the context of developing a rigorous account of logic and language.