Me> Copyright is a trade that the public makes: the right to copy art for an increase in the art output.
yfdp> I thought that the idea for copyrights is that they help stimulate innovation
I think we're agreeing here, but using different words; you seem to agree that innovation would drop off if copyright did not exist. You also seem to agree that innovation increases with copyright. Therefore a proportional, non-linear relationship exists between copyright term and innovation.
I claim that, without an artificial law in place to give artists a chance to market a unique piece of art -- copyright -- that innovation would fall off, and that innovation increases with copyright.
These statements are essentially duplicates except for one tenet -- I say that copyright is artificial, you appear to maintain that copyright is a basic, natural right. I don't think we disagree on whether or not the current implementation is flawed.
Before the advent of the copy machine (and, for music, the cassette tape), most Americans had no easily accessible method through which they could copy recording media, whether the recorded data was text, music, or anything else, for that matter. In the day of the 8-track, your average Joe HAD to buy, as he had no way to duplicate.
Looking even further back in time, there WAS no way to record certain art forms, most notably aural forms. Did this fact make every bard who played "Scarborough Fair" on his lute a criminal? No, because his society had not made the duplication of an art form -- a live duplication, but one nonetheless -- a crime. Without copyright legislation, art which could be duplicated was duplicated.
I believe that this is the base state -- no protection for the artist. When the artist creates, he is not guaranteed protection from those who wish to copy, duplicate, or take any other liberty with his work. That doesn't mean that this is the optimal state, though, any more than chaos and anarchy are the optimal state of government.
In other words, copyright is a trade. Individuals in the enacting society are giving up a portion of the freedom of expression -- the right to express something that somebody else already expressed -- in return for an increase in artistic output.
I'm interested to hear what other have to say about this.