Or, according to your own hypothesis, you're trapped in your own matrix of stories and therefore can't tell which ones are right and which are wrong.

The basic point is obvious. Sans divine revelation, it's hard to envision any other possibility.

But beyond the basics--the role of sense of self instead of just self or socially-imbued habits or whatnot--it is not so obvious or you wouldn't have had to say it.

"You can only know things from your own perspective" is the kind of statement you make not because you expect people to disagree, but rather because you want to start thinking through the consequences of this obvious observation.

But the importance of demarcation between self and superself = (sense-of-self + concept-of-reality + group-identity) is not obvious.

If we accept the superself definition, what counts as a threat to superself is not obvious, and that irrational behavior is largely/completely explicable by reactions to superself-threat is also not obvious.

What about the role of habit? What about the role of direct perception of social cues? What about rationalization of self-interest (where superself isn't on the line either way)? What about sloth? What about errors of hypercredulity rather than unwarranted pigheadedness?

Not obvious!