 Cultural variation in norms and persistent disputes over right and wrong have been thought to have significant implications for metaethics as well. The “argument from disagreement” (Loeb 1998) holds that if dispute over the permissibility of some activity or practice persists even after reasoning errors and non-moral factual disagreements have been resolved, such intractable disagreement would militate against moral realism (Mackie 1977). Empirically establishing the existence of persistent disagreement is difficult (Doris &amp; Plakias 2008), but the character of the norm system and its influence on judgment may speak to whether or not it is likely. Consider two individuals from different cultures, who have internalized divergent families of norms (individualistic and collectivist, honor based and shame based, divinity and autonomy, tight and loose, etc.) Such individuals are likely to disagree about the permissibility of a range of activities and practices, such as what counts as a fair division of resources, or whether people should get to choose who they marry, or what is and is not an appropriate way to respond to an insult. This disagreement may very well endure even in the face of agreement about the non-moral facts of the matter, and even when neither side of the dispute is being partial or making any reasoning errors. Such persistent disagreement may be explainable by appeal to differences in the individual’s respective norm systems, and to the different norms each has internalized from his or her culture (Machery et al. 2005). Empirical details of the operational principles of normative cognition—especially knowing whether and the extent to which it is informationally encapsulated, cognitively impenetrable, or otherwise recalcitrant and insensitive to other psychological processes—can help assess the plausibility of this argument.