 Models involve abstraction and idealization, but they do more than that: they help us see what our key assumptions are, identify the factors that we see as relevant (Gaus 2016, xv-xvii). Models, as techniques of idealization, do more than abstract (Weisberg 2007a, 2013). Consider the periodic table of the elements. It is an abstraction, but not a model according to Michael Weisberg. He calls abstractions like the periodic table abstract direct representations to distinguish them from models (2007b). Modeling seeks to isolate the important features of the target phenomena, allowing the modeler to understand and manipulate important elements of the phenomena in simulations. John Rawls’s representatives to the original position, for instance, are not only abstractions of real persons. They are idealizations that isolate particular aspects of persons that are relevant to justification as a choice, specifically their thin theory of rationality, and their values (in the form of primary goods). Isolating these features is important for modeling the agreement procedure in Rawls’s theory.