In the philosophical tradition that runs from Aristotle to the Renaissance, human nature, thought and life were studied as an integrated whole. After Descartes there were much sharper distinctions between epistemology, philosophy of mind, and ethics. In these essays, written over a number of years, the author illustrates the two traditions, bringing out the contrasts between them but also laying bare the medieval origins of modern philosophy of mind. He not only reviews the work of some of the greatest thinkers of the past, but also draws on their thought to contribute insights to problems which are still debated today.