This book provides a close analysis of psychological motivation as it appears in the philosophies of Plato and Aristotle. Dealing initially with Plato's tripartite model of the soul in the Republic (mind, spirit, appetite), Lorenz goes on to show how this model is taken up and refined by Aristotle. He then, in great detail, shows how such a model can give a sophisticated and powerful account of psychological motivation.

As such, the book is too detailed for the general reader, and in fact will be of interest mainly to students of Plato, Aristotle or the history of psychology. However, within this scope, it is quite fascinating. I think it also shows just how important psychology is for philosophy, for it shapes approaches to ethics and the acquisition of knowledge. To be virtuous, for example, it is perhaps essential to 'know thyself' - that is, to understand specifically what is involved in virtuous actions, and also to avoid vicious ones. Understanding - for instance - how appetite can be controlled, how imagination can be used to serve reason, etc, provide a practical basis for ethical action. Thus Lorenz does a fine job of revealing just how sophisticated and well-observed the Platonic/Aristotelian concepts of the mind were - a fact that is perhaps not so hidden in Aristotle, but, I always feel, is more obscured in Plato by virtue of the dialogue form. Lorenz's analysis, however, reveals Plato's systematic and careful development of a working psychology that will certainly send interested students back to the dialogues with fresh eyes.

Gareth Southwell is a philosopher, writer and illustrator.