 But even in the case of international human rights law, various responses have been offered. One line of response calls into question the need for the “enforcement” of international law to be global in character. The seminal work of Beth Simmons on the effectiveness of human rights treaties has shown that, insofar as membership of such treaty regimes tends to enhance human rights compliance, the mechanisms through which this is achieved are primarily those of domestic politics rather than a “white knight” foreign state or international agents (Simmons 2009). More generally, as we saw above (§2.1), states in general tend to conform with their international legal obligations (Henkin 1979: 47). Another line of response appeals not to the effectiveness of international law, but its supposed epistemic superiority, deriving from its pooling of cross-cultural knowledge in identifying solutions to common problems, such as the content of human rights (Buchanan 2008). However, it is doubtful that a bare claim to epistemic superiority can justify a claim to practical, as opposed to theoretical, authority, i.e., a claim about what we have reason to do, as opposed to what we have reason to believe (Tasioulas 2013).