Ike Elliott offers a great analogy:
Tim asserts that copyright should be adequate protection for software, and that patents for software are harmful because they inhibit innovation. I find that argument far more fascinating. I found myself comparing software to music. Music is not patentable, but it is subject to copyright. So, at the risk of oversimplifying, Tim is proposing that we treat software in the same way that we treat music. Imagine if music were patentable…what kind of changes would it have caused in the music industry? I imagine that somebody along the way would have patented the twelve-bar blues, the classic blues form that frames so many great blues songs. For the ensuing twenty years, nobody else could have written a twelve-bar blues song without “licensing the blues” from the patent holder. To me, the patentability of music would have created a grave inhibitor to creative expression, and would have deprived the world of many great musical works. I would definitely not favor patenting music.
Don Marti has drawn a similar analogy to literary patents. One can imagine a world in which novelists file patents describing the plot twists and other literary techniques they use in their novels, requiring other novelists to license the patent if they want to use that particular literary technique in their own novels. Needless to say, I don’t think very many novelists would be in favor of this plan, although the patent bar and some large book publishers might be.