[voidhorse]

I think you make a good point--there is probably a natural limit or reasonable degree of extension when it comes to using mathematics as an explanatory framework or domain language. The tendency to over-extend its application probably stems from its abstract nature--the more abstract your system or calculus, the more readily it's made to fit as a potential explanatory mechanism or language for expressing problems in a particular domain. Because mathematics is so darn abstract to begin with, it's difficult, if not impossible, to refute, a priori, someone attempting something like a Marxist topology or category theory or algebra or whatever. The application of mathematical concepts is really only refutable a posteriori, after we discover it wasn't actually a useful or sufficient explanatory mechanism for the domain. Because higher level mathematics often operates at a level in which it doesn't restrict the set of entities its variable terms could resolve to or reference, it's not possible to refute its application to anything as nonsense until we discover it as such in the process of applying it.

You also get into a bit of a tangle if you believe mathematics is not some separable set of properties or things 'in the world' but an expression of some fundamental laws of human reasoning--i.e. it captures the way in which, whether we like it or not we simply must reason, because that just happens to be how the brain is constructed. If this truly is the case, and mathematics captures some fundmanetal kernel of truth about 'proper' reasoning, it should, in theory, be widely applicable in many human endeavors. For example, someone might argue, from this perspective, that something like function application doesn't only express some property or rule of reasoning with numbers, but rather indicates a form of processing or mental operation that underlies many if not all forms of conceptual reasoning. (Frege and Leibniz are two historical figures who play with some of these ideas in their pursuit of a universal language for concepts).