John is not a troll. He’s not here to enjoy himself by stirring things up (which is what a troll is, correct me if I’m wrong). He truly believes all this stuff, and he thinks he’s informing others.
So normally the correct response, in my opinion, would be to counter his claims with facts, evidence, reason and logic. Well, I’ve tried that and it doesn’t work on John. He believes whatever he wants, regardless of any and all evidence to the contrary. That’s true of an unfortunately large number of people.
To me, it’s an important lesson, and one I’ve learned from John: There are a lot of people who think like he does, and there’s nothing you can do about it.