It is arguable that some of the most profound and perennial issues and problems of philosophy concerning the nature of human agency, the role of reason and knowledge in such agency and the moral status and place of responsibility in human action and conduct receive their sharpest definition in Plato's specific discussion in the Republic of the human value of physical activities. From this viewpoint alone, Plato's exploration of this issue might be considered a locus classicus in the philosophy of (...) sport. Indeed, it is in this place that Plato offers a highly distinctive account of the value of physical education in terms of its vital contribution to the development of a part of the soul that he characterises in terms of ?spirit?, ?energy? and/or ?initiative?. Drawing on more recent work in ethics and philosophy of action, this paper sets out to revisit and evaluate Plato's argument. While concluding that Plato's case ultimately flounders on fundamental uncertainty regarding the logical role of spirit in the explanation of agency, the paper concludes that there is much to be learned ? in the philosophy of sport and elsewhere ? from the instructive failures of Plato's argument. (shrink)