George Engel designed his biopsychosocial model to be a broad framework for medicine and psychiatry. Although the model met with great initial success, it now needs conceptual attention to make it relevant for future generations. Engel articulated the model as a version of biological systems theory, but his work is better interpreted as the beginnings of a richly nuanced philosophy of medicine. We can make this reinterpretation by connecting Engel’s work with the tradition of American pragmatism. Engel initiates inquiry like a pragmatist, he understands theory and philosophy like a pragmatist, he justifies beliefs like a pragmatist, and he understands the world like a pragmatist. By drawing out these similarities, medical and psychiatric scholars can revitalize the biopsychosocial model, and they can open medicine and psychiatry to a rich philosophic heritage and a flourishing interdisciplinary tradition.