When I was an undergraduate I barely missed taking a course from Brian Tierney—he was on leave the year I studied medieval history—but I have been instructed by him ever since. His work on the medieval origins of the concept of rights has changed the landscape of thinking about rights. In this present essay he continues his role as chief archaeologist of the doctrine of rights, laying bare here the shards of a version of natural law that, he argues, naturally grew into, or grounded the notion of rights.