Science lies at the intersection of ideas and society, at the heart of the modern human experience. The study of past science should therefore be central to our humanistic attempt to know ourselves. Nevertheless, past science is not studied as an integral whole, but from two very different and divergent perspectives: the intellectual history of science, which focuses on the development of ideas and arguments, and the social history of science, which focuses on the development of science as a social undertaking within its broader contexts. There is almost universal agreement that this bifurcation of the field is lamentable, and nearly universal disagreement about where, exactly, the problem lies. In order to identify the difficulty, this paper examines the institutional histories and disciplinary philosophies that have constituted the study of past science. I argue that science history, eventually allied itself with either History or Philosophy in order to find institutional support, thereby suffering the artificial imposition of the disciplinary prejudices of its allied fields, which lead science historians to adopt either the intellectual or the social perspective. Science history must reconcile its distinctions on its own terms, as an integrated unity with its own disciplinary bounds, and apart from History and Philosophy. As a catalyst for rapprochement, the historical and philosophical examination also yields a mapping of the field of science history that can be used to locate the problematic divisions in present scholarship and to draw new disciplinary bounds.