Full Idea
Insofar as we can honor claims about the aesthetic qualities or the interest of mathematical inquiries, we should do so by pointing to their explanatory power.
Gist of Idea
The 'beauty' or 'interest' of mathematics is just explanatory power
Source
Philip Kitcher (The Nature of Mathematical Knowledge [1984], 09.4)
Book Reference
Kitcher,Philip: 'The Nature of Mathematical Knowledge' [OUP 1984], p.212
A Reaction
I think this is a good enough account for me (but probably not for my friend Carl!). Beautiful cars are particularly streamlined. Beautiful people look particularly healthy. A beautiful idea is usually wide-ranging.
Related Idea
Idea 18078 The interest or beauty of mathematics is when it uses current knowledge to advance undestanding [Kitcher]