If I could only impress on the soul of every friend of music, and on high personages in particular, how inimitable are Mozart's works, how profound, how musically intelligent, how extraordinarily sensitive! (for this is how I understand them, how I feel them) — why then the nations would vie with each other to possess such a jewel within their frontiers. Prague should hold him fast — but should reward him, too: for without this, the history of great geniuses is sad indeed, and gives but little encouragement to posterity to further exertions; and unfortunately this is why so many promising intellects fall by the wayside.
Letter to Franz Rott (December 1787), from The collected correspondence, and London notebooks of Joseph Haydn, ed. H.C. Robbins Landon (1959), p. 73