 There are divergent approaches that have been taken within ethical theory for making sense of these salient features of moral reason. Kantians for instance, take rational agents to impose the moral law on themselves when they act, where the law in question functions as a limiting condition on their pursuit of their ends (Korsgaard 1996b, O’Neill 1989). Proponents of virtue theory take it that compliance with some agent-centered requirements is partly constitutive of being a good human being (Foot 2001). A still different class of approaches understands moral norms in essentially interpersonal terms: either as demands that are imposed by agents on each other (Darwall 2009), or as relational requirements that define what we owe to each other, and that make possible relations of mutual recognition or regard (Scanlon 1998, Wallace 2019). These are very disparate ways of conceptualizing morality as a sui genesis domain of agent-centered obligations. They have in common, however, a commitment to the idea that reflection on the nature of morality can bring to light structures of practical reason that would not otherwise be salient.