Why should modern psychotherapists be interested in philosophy, especially ancient philosophy? Why should philosophers be interested in psychotherapy? There is a sense of mutual attraction between what are today two thoroughly distinct disciplines. However, arguably it was not always the case that they were distinct. This book traces the origins of modern cognitive-behavioural therapy, noting a clear analogy with ancient philosophy. Donald Robertson skillfully combines the clinical experience of therapy and the academic grasp of philosophy to write in depth.