This chapter seeks an attitude to medicine that does not commit the error of EBM in committing to an unjustifiably rigid notion of evidence, nor the reaction of Medical Nihilism of adopting EBM’s standards of evidence and then raising the bar even higher. Cosmopolitanism is a position developed by Appiah in the context of ethical disagreement, designed to facilitate conversation without falling into epistemic relativism. The chapter unpacks Cosmopolitanism into four stances: metaphysical, epistemic, moral, and practical. It applies these stances to medicine to yield Medical Cosmopolitanism. On this realist view, medical facts (e.g., whether an intervention works, whether someone is sick) are not dependent on the perceiver. Nonetheless Cosmopolitanism promotes epistemic humility: the attitude that one has limited confidence in one’s medical beliefs (both of efficacy and of the inefficacy of someone else’s favored intervention). And it promotes Primacy of Practice: settle cases first, principles later.