Although I don't share his distaste for the moderns, I recently enjoyed rereading Bernard Berenson's essay Seeing and Knowing. Interesting for a number of reasons, here I wanted to mention it for what it says (in passing) about mathematics and formalism.
Representation is a compromise with chaos wheter visual, verbal, or musical. The compromise prolonged becomes a convention... Conventions that outlast the ages are habitual shortcuts to effective communication, whether the need be practical or representational.. . .
The alphabet is a convention. So is all arithmetical notation. So is mathematics, even the highest. Indeed it may be the most absolute of conventions, without validity outside the mind, if indeed validity exists anywhere outside our so-human minds... Our entire being and doing consists of a series of conventions permanent or succesive.
. . .
A tradition, a convention, needs constant manipulation to vivify it, to enlarge it, to keep it fresh and supple, and capable of generating problems and producing their solution. To keep a convention alive and growing fruitfully requires creative genius...
. . .
A convention is largely a matter of notation...
Bernard Berenson, Seeing and Knowing, (New York Graphic Society Art Library) 1953 (68-13052)