 Blackburn's thought is that though relativists and realists can agree that certain statements are true within a certain discourse, a quasi-realist investigates why such discourses have the structures that they do.The coherence of Blackburn's quasi-realism has been challenged most notably by the Frege–Geach problem, which assert Blackburn's position is self-contradictory.Advocates of Blackburn's view, however, would contend that quasi-realism in fact provides an antidote to the Frege–Geach problem by placing different moral claims in context.