The man that hath no music in himself, Nor is not moved with concord of sweet sounds, Is fit for treasons, stratagems and spoils; The motions of his spirit are dull as night And his affections dark as Erebus: Let no such man be trusted.................Shakespeare, Merchant of Venice, Act V, Scene 1
Yond Cassius has a lean and hungry look. He thinks too much: such men are dangerous......Shakespeare, Julius Caesar Act I, Scene 2.
For me, mathematics and music are two of the most enigmatic and interesting human creations. Neither one has an obvious connection to the business of survival in a Darwinian world. Language is probably the connecting thread. Music and math each have their intricate vocabularies and grammars. Of course appreciation of music is a lot more common than regard for the more austere beauties of mathematics.
And Cassius probably wasn't thinking about mathematics.