the argument "A implies B" is not universally compelling unless every rational agent must accept that "P(B | A) > P(B | !A)"
More colloquially, one property of universally compelling evidence might be that all rational agents must agree on the particular direction a particular piece of evidence should adjust a particular prior.
You're just passing the recursive buck over to "rational". Taboo rational, and see what you get out; I suspect it will be something along the lines of "minds that determine the right direction to shift the evidence in every case", which, notably, doesn't include humans even if you assume that there is an objectively decidable "rational" direction. There is no objectively determinable method to determine what the correct direction to shift is in any case; imagine an agent with anti-occamian priors, who believes that because th... (read more)
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