Full Idea
Kitcher says maths is an 'idealising theory', like some in physics; maths idealises features of the world, and practical operations, such as segregating and matching (numbering), measuring, cutting, moving, assembling (geometry), and collecting (sets).
Gist of Idea
Kitcher says maths is an idealisation of the world, and our operations in dealing with it
Source
report of Philip Kitcher (The Nature of Mathematical Knowledge [1984]) by Michael D. Resnik - Maths as a Science of Patterns One.4.2.2
Book Reference
Resnik,Michael D.: 'Mathematics as a Science of Patterns' [OUP 1999], p.64
A Reaction
This seems to be an interesting line, which is trying to be fairly empirical, and avoid basing mathematics on purely a priori understanding. Nevertheless, we do not learn idealisation from experience. Resnik labels Kitcher an anti-realist.