Supported by the end of P2 and the middle of P3. The author states that patent protection is available only for products of invention, which things such as a law of nature are not. This supports the claim that scientific principles are not patentable. The author also states that copyright law protects only the particular way in which underlying ideas are expressed. Scientific principles aren’t a particular expressions of ideas.

We don’t know the “primary” value of patents. In addition, generic principles are not patentable. So it wouldn’t make sense for the value of patents to lie in their protection of generic principles, because this protection doesn’t exist for generic principles.

We don’t know whether items that get patent protection “usually” also get copyright protection. The only things that are mentioned as patentable are things that are products of invention, such as a design of a process. But are most of these things also considered expressions of an underlying principle, such that they also get copyright protection? We don’t know.

Actually, the author suggests that the algorithm underlying a software program does not currently have any legal protection. This is why proponents of patents want algorithms to be protected. But currently, we have no reason to think that using an algorithm requires permission from the copyright holder, since the algorithm can’t be copyrighted.

We don’t know what proportion of commercially available software has illegally copycatted code. Although the author notes that it’s easy and expensive to produce copycat computer programs, this doesn’t imply that most software that’s commercially available involves copycatting.