Full Idea
§62 of Frege's 'Grundlagen' is arguably the most pregnant philosophical paragraph ever written; ..it is the very first example of what has become known as the 'linguistic turn' in philosophy. His enquiry into numbers focuses on the sense of sentences.
Gist of Idea
Frege initiated linguistic philosophy, studying number through the sense of sentences
Source
report of Gottlob Frege (Grundlagen der Arithmetik (Foundations) [1884], §62) by Michael Dummett - Frege philosophy of mathematics
Book Reference
Dummett,Michael: 'Frege: philosophy of mathematics' [Duckworth 1991], p.111
A Reaction
Dummett is a great fan of this, possibly the last great fan. It is undeniable that Frege has found one way to get at the problem, but I doubt if it is the only way.