So, while life experience may be a fallacious argument to win an argument; but at the same time there may really be some things learnt over the years that are simply hard to explain. This is sometimes mirrored by younger people who think that precisely because they are not blinded by life experience, they can see things clearer.

The problem to state this all in strictly Bayesian terms is that so much of the reasons why we think A or B is implicit are only accessible through intuition. Thus, in a discussion it may be quite hard to make all knowledge common. In practice, nobody is a strict Bayesian, people's opinions will be based on implicit assumption.

One interesting thought experiment to think of this: suppose you could meet your younger self, say 5-10-20 years ago; and let's say that you already were a fairly rational person then. How hard would it be to convince your younger self of the things of you think differently now than you did back then?