Published online by Cambridge University Press: 01 April 2022
In this paper, I examine the claim that any physical theory will have an extremely limited domain of application because 1) we have to use distinct theories to model different situations in the world and 2) no theory has enough textbook models to handle anything beyond a highly simplified situation. Against the first claim, I show that many examples used to bolster it are actually instances of application of the very same classical theory rather than disjoint theories. Thus, there is a hidden unity to the world of classical physics that is usually overlooked (by, for example, Nancy Cartwright who argues for the claims above). Against the second claim, I show that the practice of classical physics involves an enormous (infinite) number of models the use of which cannot be written off as merely ad hoc. Thus, although classical physics cannot, of course, model every situation in nature, it has a much larger domain than some would have us believe.
I would like to thank Robert Batterman for reading a previous draft of this paper and an anonymous reviewer for this journal for giving extremely helpful comments. I would especially like to thank Mark Wilson both for generous help with previous drafts and for getting me interested in the structure of classical physics in the first place. All errors that remain are, of course, my own.