 However, this raised an important question: Can one tell a story bridging the models at the atomic scale and those at the continuum scale of centimeters and greater? Reductionists typically believe that it is possible to connect, and presumably to derive, the continuum models starting from atomic scale details. There has been a battle for two centuries, at least, between those who are persuaded that such a bottom-up story can be told, and those such as Duhem, Mach, and others who have championed a top-down modeling strategies. In the 19th century this took the form of a heated dispute between so-called rari-constancy and multi-constancy theorists who, respectively, tried to determine the continuum equations from top-down (ignoring unknown micro details) considerations, and theorists trying to determine the continuum equations with small scale atomic assumptions guiding the constructions. In fact, surprisingly, the former prevailed. (Todhunter and Pearson 1960; Batterman 2012) 