The thing is you cannot FORCE or even logic with some people to get them to understand REALITY when they din't want to. Sadly even actual proof usually doesn't phase people like that.
My dad had thinking like that. Luckily there weren't the scams there are today when he was alive.....but when he made his mind up to believing things were the way he knew they were, there was no rational talking to him & he would actually argue with others & make a fool out of himself (absolutely no alcohol involved).