[theptip]

> the brain can be simplified as a bayesian filter

I agree with everything else in your post, but just wanted to note that while this is true to some extent, the brain is much less rational than a pure Bayesian inference system; there are a lot of baked in heuristics designed to short-circuit the collection of data that would be required to make high-quality Bayesian inferences.

This is why excessive stereotyping and tribalism are a fundamental human trait; a pure Bayesian system wouldn't jump to conclusions as quickly as humans do, nor would it refuse to change its mind from those hastily-formed opinions.