Jeroen Hellingman (Mailing List Account) wrote:
I've been studying this idea a bit further, and think there is a fallacy in this reasoning, that is, you are giving the author his present value at publication, but you are not giving it at the present, but spread out of N years.... Under your assumptions, he can consume A forever from day zero with perpeptual copyright, but he will have to wait for N years (and save everything, except interest) before he can consume A forever after this deal. Since most people don't life forever, this isn't a very good deal.
I think you can still make a good economical case for a copyright lasting in the order of 28 years, but that will require some more math, and statistics about sales patterns of common copyrighted works. That's why I wanted to throw in the VAT, or even some arbitrary valuation of elements borrowed from the public domain, so that we can claim a work for the public when the author has earned roughly 85 % of its value according to very conservative estimates.
The assumption is this style of scheme is that the creator should retain the right to a work as long as there remains significant value in the work. No matter where you draw the line, though, there exist some works of enduring value, which happen to be those works which are most cared about. While you would say, the collective value of free use of old ephemera is worth the value lost to the creators of enduring works, it could just as easily be said that the value lost to the creators of enduring works cannot possibly be worth the use of those works that have lost all value. The same assumption you start with can be used to justify perpetual copyright! If we instead say that the public should invest in a work the value of that work, but no more than the value of that work, then you reach my result. After N years, the value of the public's investment in the work, plus interest on that investment, has reached the value of that work. Causing the public to invest still more in the work is inefficient, because the public cannot both invest in the old work and new work. -- RS