Here’s a good article on classical music. There are a lot of interesting issues here, but I liked this in particular:

Over the course of the nineteenth century, the concept of a musical canon emerged and displaced the zeal for new music in concert programming. Yet the updating of scores continued. Gustav Mahler added new parts for horns, trombones, and other instruments when he conducted Beethoven’s symphonies. An influential edition of Beethoven’s piano sonatas by the pianist and conductor Hans von Bülow recommended that pianists substitute Liszt’s ending of the Hammerklavier Sonata for Beethoven’s own, “to give the closing measures the requisite brilliancy.”

Even in the canon-revering twentieth century, the teleologists remained cheeky. Arnold Schoenberg explained his reorchestration of Handel’s Concerti Grossi, op. 6, as remedying an “insufficiency with respect to thematic invention and development [that] could satisfy no sincere contemporary of ours.” At the start of a 1927 recording of Chopin’s Black Key Étude, the pianist Vladimir de Pachmann announces: “The left hand of this étude is entirely altered from Chopin: it’s better, modernized, more melodic, you know.” A contemporary listener, drawn to Beethoven, Handel, and Chopin precisely for what is unique in their voice and sensibility, can only marvel at the confidence with which earlier generations declared such music in need of improvement…

The naysayers pointed out that the context of musical performance has changed so radically from the pre-Romantic era that we cannot hope to re-create its original meaning. For most of European history, music belonged to social ritual, whether it accompanied worship, paid homage to a king, or provided background for a feast. A large concert hall filled with silent listeners, focused intently on an ensemble of well-fed professionals still in possession of most of their teeth, has no counterpart in early-music history. Early-music proponents, the detractors added, are highly selective in their use of historical evidence. No one today conducts the operas of Jean-Baptiste Lully, for example, by pounding a staff on the floor, as conductors did in the court of Louis XIV to try to keep time in an ensemble of less-than-perfectly trained musicians.

These paragraph echo Foucault’s idea of the modern birth of the author. We seem to be very obsessed with originality, plagiarism, and the right interpretation of the original author. It is interesting that people in the past saw art more as craftsmanship belonging to the common deposit of society.