"What is the definition of that which is named ‘soul?’ Can we give it any other definition than that stated just now: ‘the motion able to move itself?’" (Laws 895e). The essays in this volume touch upon the central theme in Plato’s late dialogues of the soul as the principle of self-motion and vitality. They discuss in particular the soul’s relation to the intelligible world and understanding, as well as its cosmic and socio-political dimensions.