The article offers an approach to inquiry about, the foundation of medical ethics by addressing three areas of conceptual presupposition basic to medical ethical theory. First, medical ethics must presuppose a view about the nature of medicine. it is argued that the view required by a cogent medical morality entails that medicine be seen both as a healing relationship and as a practical art. Three ways in which medicine inherently involves values and valuation are presented as important, i.e., in being aimed at the good of health, in being a cognitive art evaluating towards that good, and as a manifestation of a virtuous disposition concerning that good. Finally, a value ontology drawn from these considerations is seen as necessarily underlying medical ethics. A set of three such basic values are promoted as crucial: the value of health; the value of the individual patient; and the value of altruism that mediates the class of potential patients.