
Letter to Leopold Mozart (11 September 1778), from Wolfgang Amadé Mozart by Georg Knepler (1991), trans. J. Bradford Robinson [Cambridge University Press, 1994, ], p. 12.
Variant: A fellow of mediocre talent will remain a mediocrity, whether he travels or not; but one of superior talent (which without impiety I cannot deny that I possess) will go to seed if he always remains in the same place.