 Proposals by other philosophers are related to Carnap’s view. Resnik (1997, Part Two) has put forward a postulational epistemology for the existence of mathematical objects. According to this view, all one has to do to ensure the existence of mathematical objects is to use a language to posit mathematical objects and to establish a consistent mathematical theory for  them.[16]  Nevertheless, their existence does not result from their being posited. Instead, we recognize those objects as existent because a consistent mathematical theory for them has been developed. Resnik requires both a linguistic stipulation for considering mathematical objects and a coherency condition for recognizing them as existent. Thomasson (2015, 30–34) advocates for an approach which she takes to be inherited from Carnap. She calls it easy ontology. Since she is not trying to find ultimate categories or a definitive list of basic (abstract or concrete) objects, she prefers a simpler kind of realism (see Thomasson 2015, 145–158). She argues that everyday uses of existential statements provide acceptable ontological commitments when those assertions are supported either by empirical evidence or merely by the rules of use that govern general terms (e.g., sortal terms); in both cases she says that “application conditions” for a general term are fulfilled (see Thomasson 2015, 86, 89–95). She, too, therefore offers a criterion of linguistic rules for accepting abstract objects. Given her defense of simple realism, it appears that she takes both observable objects and theoretical entities in science as concrete.