 The case for Humean constructivism rests on the alleged inadequacy of competing views: “it is what we are forced to by the untenability of realism plus the failure of Kantian versions of metaethical constructivism” (Street 2010: 371). Humean constructivism denies that normative truths are independent of the deliverances of practical reasoning (Bagnoli 2002: 131; Street 2008a, 2010, 2012; Velleman 2009; Lenman 2010, 2012). To this extent, Humean constructivism builds on the Kantian insight that normative truths are not simply “out there”, as realists suppose. In contrast to Kantian constructivism, however, Humean constructivists abandon the claim that moral obligations are requirements of practical reason. The constitutive norms of practical reason may favor morality, but do not require it (Street 2012; Velleman 2009: 150–154; Lenman 2010: 192). Thus, Humeans maintain that an ideally coherent Caligula who values torturing people for fun is conceivable. Such a person would have reasons for torturing people, which is just to say that the value of humanity is not a constitutive norm of reasoning (Street 2010: 371; Street 2009, 2012). Humean constructivism also rejects the Kantian claim that there are universal rational norms that bind all rational agents. For instance, Street argues that “the substantive content of a given agent’s reasons is a function of his or her particular, contingently given, evaluative starting points” (Street 2010, see also Lenman 2010: 180–181). Consequently, “truth and falsity in the normative domain must always be relativized to a particular practical point of view” (Street 2008a: 224). Agreement among various practical standpoints is possible but it is not guaranteed by facts about the nature of reason or the principles of reason that are authoritative for all rational agents. Humeans hold that there is nothing alarming about the sort of relativism that their position implies (Street 2008a: 245). Even though moral norms are not necessary requirements of reason, there is a sense in which they are not contingent because they play a large role in our lives. Furthermore, by analogy with attitudes such as love, which is both contingent and compelling, Street argues that the fact that moral commitments are contingent does not weaken their normative force. The latter claim has been disputed on the ground that the driving force of love should be distinguished from its normative authority (Bratman 2012).