I liked the discussion of Paganism at the end, though I disagree that they are holding all of this information in their heads.
From being raised Catholic and taking lots of courses in improv, I've noticed how good people can be at making shit up that sounds right. In Catholicism, there's lot of rules to follow, and everyone acts like they know why. In truth, I'm not sure most Christians in general know why they follow certain traditions or ceremonies, but if you pushed them on it, they'd have an answer. People can fill in gaps by giving a correct-sounding answer, but it doesn't make any sense. Improv is very similar, because there are a lot of techniques and axioms and any bad scene can be explained with one of them.
It's a combination of having repeatable phrases, undefinable forces, and self-confidence. You hear enough of the parlance, it gets in your head, and then you start filling the gaps in yourself with your own self-delusion. Pagans are engaging in a sort of spiritual hedonism. If it feels good, believe it. The problem with paganism is that there are no real central tenets, no guiding figure, no traditions. It's a bunch of non-Christian beliefs Mod-Podged together by burnt-out Baby Boomers. Then the internet gets involved and Harry Potter somehow becomes real.
What's troubling is that we are all capable of this self-delusion. We can all convince ourselves we know the truth when we are wrong. Not necessarily about the big stuff, but even person to person, day to day. The only real way to be sure you'll get to the truth is to open yourself to the possibility of being incorrect. Just as Socrates said, the only thing I know is that I know nothing. Pretty smart stuff. That's why Socrates as my personal savior.
Have you heard the Good News? You're an idiot.