Theorists of health have, to this point, focused exclusively on trying to define a state—health—that an organism might be in. I argue that they have overlooked the possibility of a comparativist theory of health, which would begin by defining a relation—healthier than—that holds between two organisms or two possible states of the same organism. I show that a comparativist approach to health has a number of attractive features, and has important implications for philosophers of medicine, bioethicists, health economists, and policy (...) makers. (shrink)