The historical and philosophical quest for the origin of the work-concept must not bypass or neglect the phenomenon – prevalent in the seventeenth and eighteenth centuries – of multiple versions or configurations of one and the same musical work. It is, in fact, this very phenomenon that confirms the existence of the work-concept in the eighteenth century and even earlier. For why should a composer like Heinrich Schutz revise his German Magnificat swv 494 in order to make it suitable for publication in his opus ultimum? Why should Johann Sebastian Bach undertake the trouble of polishing and transposing his C minor Partita bwv 831 for inclusion in the Second Part of his Clavier-Übung, an exemplary juxtaposition of Italian and French style models? These two randomly chosen examples could be expanded in several directions.

Considerations made by composers in conjunction with publication projects may shed light on and help us understand significant constituent elements of the work-concept. A particular case in point is offered by two works that figure most prominently in Mozart’s publication plans in 1785 and 1788 respectively, his newest and most ambitious piano sonatas. The works in question represent the first such works composed and published in Vienna, one in C minor, k. 475+457, and one in F major, k. 533+494. All previous piano sonatas had been written before Mozart established residence there in 1781. However, it was in Vienna where he decided to offer the interested public two sets of earlier keyboard sonatas, k. 330–332 as Op. vi (Artaria, 1784) and k. 333 along with k. 284 and k. 454 for piano and violin as Op. vii (Torricella, 1784). We do not know whether it was the success of and response to these publications or a renewed interest in the sonata genre resulting from his intense engagement with composing six string quartets between late 1782 and early 1785 that may have encouraged Mozart to resume writing piano sonatas. At any rate, the two works in question, k. 475+457 and k. 533+494, stand out in a several ways, not only in terms of unprecedented musical weight in the realm of piano sonatas but also with regard to their mode of publication as single works. Mozart’s previous sonata publications followed the widely established pattern of printing a set of preferably three or six works rather than a single piece.