Does copyright protection offer the best means of stimulating the production of expressive works? Maybe it does now. If so, however, copyright will probably over-protect expressive works in coming years. We should hope that it will, at any rate, given that human progress will render copyright obsolete.
It costs a great deal to produce the first copy of many expressive works, including such notably valuable ones as movies, books, and software. Copyright law helps to reassure would-be authors that they will recover those fixed, up-front costs. Alternative mechanisms—such as tips, patronage, automated rights management, and contracts—risk providing too little protection against unauthorized copying, leading to market failure. Hence the case for copyright.
As the market in expressive works grows, however, it promises to outgrow copyright law. As people join that market, whether by entering by the world or by escaping isolation, they offer authors new sources of revenue. Given the low marginal costs of reproducing and distributing expressive works, those larger audiences will tend to reward authors with larger profits. Holding all else equal, copyright will at some point give more protection than necessary, and its costs will outweigh its benefits.
Perhaps a lightly populated, large, and semi-agricultural nation, with slow and costly communications, required copyright law to encourage an adequate production of expressive works. It seems that those who wrote and ratified the U.S. Constitution thought as much. But however well that justification for copyright worked in years past, it works decreasingly well now. Looking forward, we can easily imagine a world where generosity, technology, and common law rights improve on, and thus replace, copyright law.
[Crossposted to The Technology Liberation Front.]