Full Idea
As, in the logicist view, mathematics is about nothing particular, it is little wonder that nothing in particular needs to be observed in order to acquire mathematical knowledge.
Gist of Idea
If mathematics is not about particulars, observing particulars must be irrelevant
Source
A.George / D.J.Velleman (Philosophies of Mathematics [2002])
Book Reference
George,A/Velleman D.J.: 'Philosophies of Mathematics' [Blackwell 2002], p.214
A Reaction
At the very least we can say that no one would have even dreamt of the general system of arithmetic is they hadn't had experience of the particulars. Frege thought generality ensured applicability, but extreme generality might entail irrelevance.