For some time, a spirited debate has been raging over what to make of the physics of phase transitions---for instance, the steam rising from the surface of my (all-too-finite) cup of coffee. One party to the debate maintains that my coffee must be idealized as infinite in order to accommodate phase transition phenomena. Another maintains that de-idealized finite models of statistical physics should be adequate to those phenomena. Rather than taking sides, Ruetsche will offer the speculative diagnosis that what's really at stake in the debate is the status of "fundamental" physics.  Suggesting, perhaps heretically, that the physics at hand is not fundamental, she will try to shift attention to something we, as philosophers and historians of science, might do other than taking sides. That something is thinking about ways aspects of our current theories might be surrogates for future physics.