Biologists study living things, but what do philosophers of biology study? A cynic might say “their own navels,” but I am no cynic. A better answer is that philosophers of biology, and philosophers of science generally, study science. Ours is a second-order, not a first-order, subject. In this respect, philosophy of science is similar to history and sociology of science. A difference may be found in the fact that historians and sociologists study science as it is, whereas philosophers of science study science as it ought to be. Philosophy of science is a normative discipline, its goal being to distinguish good science from bad, better scientific practices from worse
