 Not surprisingly, proponents of intrinsic attribute accounts, such as McMahan, are unsympathetic with the claim that “facts about the nature of some individuals could determine how other individuals that lack that nature ought to be treated” (McMahan 2008, 85). Like other critics, McMahan sees this claim as requiring a kind of “moral alchemy” that transmutes factual claims about some individuals into moral demands concerning others. But for those who regard humanity as a “thick” concept  (5.2),  no alchemy is required. The concept of a human being is a normative one, conferring rights on all those who fall under it and imposing moral demands on those who understand and apply it.