Queen Michael said:
Do you ever hear someone express views that you think that at some level they should understand don't make any sense? Like when my grandmother didn't agree with me that Michael Jackson had been framed for pederasty crimes by people who wanted to get a big bunch of dollars from him, because to wuote her, "Do you really think people would do that kind of thing for money?" Leaving aside the issue of whether Michael was guilty or not, at some level she must have known that people will lie for money.
So... what have you heard people say or believe or think that at some level they must have known was untrue?
Here's the massive contradiction in what you're saying here. I don't know if Michael Jackson was framed or not - I'm not particularly interested in the subject and haven't looked it up. I have no idea what the evidence is either way.
Now if the evidence proves conclusively that he was, or wasn't, framed, then you can say that your grandmother is wrong (or right). That's a question of FACT. If there's not such conclusive evidence (which is what I'm gathering from your post) then your grandmother's statement is an opinion, and so is yours. And that's where we run into difficulties because an opinion can't be "true" or "untrue". A belief can be either provable or unprovable, and again, if it's the latter, it can't be said to be "true" or "untrue". It depends on the observations and life experiences of the believer.
Maybe your grandmother has never met anybody who would commit such a cynical, self-serving act, but has met or read about people who would molest children. Maybe, given her experiences in live, she finds the notion of a pedophile singer plausible, but the notion that people would cynically exploit an innocent person in that way impossible (or just emotionally intolerable). My point is that there are SO MANY different things that influence a person when deciding a question like this one.
A lot of people believe in some kind of creator or God (myself not being one of them). There's no empirical evidence for the existence of any God, so their belief is based on other factors - upbringing, a view of the world that includes the supernatural, or just a world-view that sees complexity as evidence of some kind of creator. This world view is pretty much the opposite of my own. I'm not judging the "objective validity" of either viewpoint. I'm just saying that their definition of "reasonable" is entirely different to my own, because we have different experiences and therefore a different view of the world.
So when you say "untrue", what you really mean is "unreasonable, according to my personal experience". To me the notions of racism or anti-gay prejudice are unreasonable (and repugnant); but I doubt I'd be able to convince a member of Westboro Baptist Church of the latter. Why should things be any different in terms of the less controversial questions? If we all thought exactly the same way, the world would be a much more boring - and probably a much more terrible - place to live.