This is a book about Thomas Aquinas as a philosopher, written for readers who may not necessarily share his theological interests and beliefs. Apart from his commentaries on Aristotle, Aquinas wrote little of an explicitly philosophical nature; but his theological works contain philosophical insights which entitle him to be considered as one of the world's great philosophers. The book is divided into three chapters. The first is an account of Aquinas's life and works, and as assessment of his significance for contemporary philosophy. The second is a sketch of the major concepts of Aquinas's metaphysical system: it includes a discussion of the doctrine of Being, which is one of the most famous but also, Anthony Kenny argues, the most overrated elements in his philosophy. The third chapter is devoted to Aquinas's philosophy of mind, which is less well known but far more rewarding to study.