Here, in the last pages of the "Abegg" Variations, Schumann plays the motto theme A-B-E-G-G (B in German notation is the English Bb) not by sounding the last four notes but by taking them away, one by one, from, the chord of Bb-E-G. This is the first time in history that a melody is signified not by the attack but by the release of a series of notes. The motto, however, ends with a repeated final G. If the motto is played by releasing each successive note, we are faced with a paradox: when the G is released once on the piano, it is no longer there to be released again-the motto is not only unplayable as conceived but unimaginable. Schumann signifies as much by another paradox: he adds accents to the sustained notes.

Ch. 1 : Music and Sound - The Romantic Generation (1995)