Is the intent to provide incentive to create, or to provide opportunity to create? To me, providing incentive is the equivalent of dangling a carrot in front of the hitherto idle musician. He will only create when the reward is sufficient. Is that a philosophy within which great art is created?
The opportunistic musician, on the other hand, creates constantly without needing any incentive to do so – the copyright privilege, when invoked, lends to him the economic opportunity to devote his time exclusively to artistic pursuit.
I believe there is a fine distinction here that is missed by both sides of the copyright debate. Incentive is a nice thing economically, but pure incentive, like the ownership metaphor, should not be the end goal of copyright – copyright should be viewed first and foremost as a mechanism to provide _opportunity_ to advance the sciences and useful arts. Would-be artists who only cash in and create something when the incentive is sufficient were not who the framers had in mind… and since they are only pandering and not advancing the state of the art, we shouldn't pay them much heed when they demand more and more protection in order to continue creating.
“The primary objective of copyright is not to reward the labor of authors, but '[t]o promote the Progress of Science and useful Arts.'” – Justice Sandra Day O'Connor, writing for the majority in Feist v. Rural Telephone Service Company, Inc. (1991)