Legal philosophers have been preoccupied with specifying the differences between two systems of normative guidance that are omnipresent in all modern human societies: law and morality. Positivists such as Kelsen, Hart, and Raz propose a solution to this “Demarcation Problem” according to which the legal validity of a norm can not depend on its being morally valid, either in all or at least some possible legal systems. The proposed analysis purports to specify the essential and necessary features of law in virtue of which this is true. Yet the concept of law is an “artifact concept,” that is, a concept that picks out a phenomenon that owes its existence to human activities. Artifact concepts, even simple ones like “chair,” are notoriously resistant to analyses in terms of their essential attributes, precisely because they are hostage to human ends and purposes, and also can not be individuated by their natural properties. 20th-century philosophy of science dealt with a kindred Demarcation Problem: how to demarcate epistemically reliable forms of inquiry from epistemically unreliable ones, that is, how to demarcate science from pseudo-science or nonsense. Like the legal philosophers, they sought to identify the essential properties of a human artifact (namely, science). They failed, and spectacularly so, which led some philosopher to wonder, “Why does solving the Demarcation Problem matter?” This essay develops the lessons for legal philosophy from this episode and its philosophical aftermath, and concludes that, lest we want to become embroiled in pointless Fullerian speculations about the effects of jurisprudential doctrines on behavior, it is time to abandon the Demarcation Problem in jurisprudence.