Charles Rosen Quote

The musical language which made the classical style possible is that of tonality, which was not a massive, immobile system but a living, gradually changing language from its beginning. It had reached a new and important turning point just before the style of Haydn and Mozart took shape.

Part I. Introduction. 1. The Musical Language of the Late Eighteenth Century - Classical Style: Haydn, Mozart, Beethoven (Expanded edition, 1997)