Medicine has been a very fruitful source of significant issues for philosophy over the last 30 years. The vast majority of the issues discussed have been normative – they have been problems in morality and political philosophy that now make up the field called bioethics. However, biomedical science presents many other philosophical questions that have gotten relatively little attention, particularly topics in metaphysics, epistemology and philosophy of science. This volume focuses on problems in these areas as they surface in biomedical science. Important changes in philosophy make biomedical science an especially int- esting area of inquiry. Contemporary philosophy is largely naturalistic in approach – it takes philosophy to be constrained by the results of the natural sciences and able to contribute to the natural sciences as well. Exactly what those constraints and contributions should be is a matter of controversy. What is not controversial is that important questions in philosophy of science and metaphysics are raised by the practice of science. Physics, biology, and economics have all drawn extensive phi- sophical analysis, so much so that philosophical study of these areas have become specialized subdisciplines within philosophy of science. Philosophy of medicine approached from the perspective of philosophy of science – with important exc- tions (Schaffner, 1993; Thagard, 2000) – has been relatively undeveloped. Nonetheless, medicine should have a central place in epistemological and metaphysical debates over science.