 A number of philosophers explicitly reject the requirement that a good characterization of logical truth should provide a conceptual analysis, and (at least for the sake of argument) do not question the usual view of set-theoretic claims as non-modal, but have argued that the universe of set-theoretic structures somehow models the universe of possible structures (or at least the universe of possible set-theoretic structures; see McGee 1992, Shapiro 1998, Sagi 2014). In this indirect sense, the characterization in terms of model-theoretic validity would grasp part of the strong modal force that logical truths are often perceived to possess. McGee (1992) gives an elegant argument for this idea: it is reasonable to think that given any set-theoretic structure, even one construed out of non-mathematical individuals, actualized or not, there is a set-theoretic structure isomorphic to it but construed exclusively out of pure sets; but any such pure set-theoretic structure is, on the usual view, an actualized existent; so every possible set-theoretic structure is modeled by a set-theoretic structure, as desired. (The significance of this relies on the fact that in Fregean languages a formula is true in a structure if and only if it is true in all the structures isomorphic to it.)