I don't think I follow what you're trying to say. My point is that whether something can be accidentally infringed or not is a weird criterion to use to separate ethical and unethical restraints on free expression. We create civil liability for lots of things that happen on accident. I think the ethical discussion, if there is one, centers on whether these restraints on free expression or valid in the first place.

> Second, I am not referring to trademarks as presently defined.

You said that trademarks/copyright could be distinguished from patent based on accidental infringement. You could define trademarks in a way where accidental infringement didn't create liability, but you could define patents that way too. Neither are defined that way presently.

> Third, requiring someone to prove their innocence violates one of the most basic principles of ethical justice.

I'm not sure what 3rd grade reading level principles of ethical justice you're talking about. We require defendants to prove certain affirmative defenses all the time, generally in cases where something is unlikely to have occurred without wrongdoing. E.g. if you kill somebody in self defense, you're obligated to at least present evidence that it was in self-defense. And of course we're talking about civil litigation here, not criminal litigation. "Innocence" is the wrong terminology.

> Fourth, it is irrelevant to this discussion how often it is, but clearly, 40,000 software patents filed per year constitutes a lot of opportunity for infringement. If you are doing something meaningful and interesting, you are likely violating a patent. But again, this point is not essential to the main issue.

I'm not the one who said that people "often" accidentally infringe patents, you were.