 Pure relative identity trinitarianism depends on the controversial claim that there’s no such relation as (non-sortal-relative, absolute) identity. Most philosophers hold, to the contrary, that the identity relation and its logic are well-understood; such are expounded in recent logic text-books, and philosophers frequently argue in ways that assume there is such a relation as identity (Baber 2015, 165; Layman 2016, 141). One might turn to a weaker relative identity doctrine; outside the context of the Trinity, philosopher Nicholas Griffin (1977; cf. Rea 2003, 435–6) has argued that while there are identity relations, they are not basic, but must be understood in terms of relative identity relations. On either view, relative identity relations are fundamental.