With regard to the scientic realism/anti-realism debate (which I was talking about at the LSE recently), one of the positions in-between standard scientific realism and scientific anti-realism is the position called structural realism. I just came across an interesting quote from physicist Steven Weinberg that provides some support for structural realism:

So the mathematical structures that physicists develop in obedience to physical principles have an odd kind of portability. They can be carried over from one conceptual environment to another and serve many different purposes… . We are led to these beautiful structures by physical principles, but the beauty sometimes survives when the principles themselves do not. 

That’s from his 1992 book Dreams of a Final Theory, p. 152 in the Vintage paperback edition.