Abstract
This paper pursues Ernan McMullin‘s claim ("Virtues of a Good Theory" and related papers on theory-choice) that talk of theory virtues exposes a fault-line in philosophy of science separating "very different visions" of scientific theorizing. It argues that connections between theory virtues and virtue epistemology are substantive rather than ornamental, since both address underdetermination problems in science, helping us to understand the objectivity of theory choice and more specifically what I term the ampliative adequacy of scientific theories. The paper argues therefore that virtue epistemologies can make substantial contributions to the epistemology and methodology of the sciences, helping to bridge the gulf between realists and anti-realists, and to re-enforce moderation over claims about the implications of underdetermination problems for scientific inquiry. It finally makes and develops the suggestion that virtue epistemologies, at least of the kind developed here, offer support to the position that philosophers of science know as normative naturalism.