Axel Horns is discussing the relation between software patents and copyright here.
He says that there is a “myth” of software patents being used as a tool of dispossession against the copyright programmers earned by writing something. This is a “myth”, in his view, since programmers need to check for patents, just as someone who wants to build somewhere needs to check the property status of the real estate in question.
He then goes on, however, to explain that it is actually impossible for most software authors to do the patent check. That means he is refuting his own point.
I entered the following comment at his blog:
From your point of view, anyone who wants to write a program needs to check first if there any prohibitions on writing it. No one does that, since it would be much too expensive, as you explain convincingly above.
If software patents could be checked as easily as the ownership of some real estate, people would have much less reason to complain. That, however, is not reality. Your point of view that programmers need to check patents before writing something is refuted by your own analysis.