Plato was more than a philosopher; he was a master of literary composition who frequently wrote in colourful style. His works are not treatises; instead they range with nimble wit over many topics, only some of which are in any sense philosophical. But at the heart of his work there is material that is as definitely philosophical as anything in the most technical academic products in the twenty-four centuries that have followed his pioneering labours. So this book is about Plato and his philosophy. I shall extract arguments and ideas from a variety of his texts, written at various stages over his long literary career, and shall group them according to the philosophical topic areas on which they impinge. It is certainly worth reading Plato's works as he wrote them, so that you can savour the appetizing surrounds in which he wraps his arguments. But it is the arguments that count.

Philosophy today is divided into many sub-specialisms: metaphysics, epistemology, logic, ethics, philosophy of mind, philosophy of language, to name just a few. We owe this contemporary academic division – as also the larger divisions between different fields of intellectual study – to Aristotle; and perhaps that process of division starts with Plato. He was given to classification and applied it to some cases of intellectual and sub-intellectual skills, although his own philosophizing does not deal in the modern distinctions within the activity.