Full Idea
Experience with nature is undoubtedly the source of our most basic 'mathematical intuitions', even if it is unfashionable to say so.
Gist of Idea
It is unfashionable, but most mathematical intuitions come from nature
Source
Hilary Putnam (Models and Reality [1977], p.424)
Book Reference
'Philosophy of Mathematics: readings (2nd)', ed/tr. Benacerraf/Putnam [CUP 1983], p.424
A Reaction
Correct. I find it quite bewildering how Frege has managed to so discredit all empirical and psychological approaches to mathematics that it has become a heresy to say such things.