I'm having a hard time interpreting this; are you saying that because people who believe in religions don't unanimously agree that implies all relgions are false?
No, what I'm saying is that the ways in which they violently disagree mean that their epistemology is useless. At the very least N-1 of N religions are wrong, so I wouldn't ascribe too much weight to their claims in general. If I want to reduce my uncertainty about something in the universe, I won't go to the people who are at best 30% likely to give me a correct answer.
While disagreement is often violent, I think if you look closely most of these disagreements are actually politically motivated rather than reflecting deep divisions in core beliefs. Prior to the advent of nationalism this was simply a good way to rally the troops for whichever geopolitical objective.
In terms of core beliefs, I think your estimate is rather low. Obviously it depends on how you weight it, but the core beliefs of the Abrahamic relgions and even Hinudism and Buddhism have a lot in common.
> At the very least N-1 of N religions are wrong
I will take it further than this: 100% of all beliefs are at least partially wrong. Ultimately, one has to ascribe weight to something.
> but the core beliefs of the Abrahamic relgions and even Hinudism and Buddhism have a lot in common.
The problem is not the things they have in common, the problem is the claims for which you can't figure out the truth value in any way, regardless of whether they're shared or not.
> I will take it further than this: 100% of all beliefs are at least partially wrong.
Fortunately most beliefs held by people are not considered dogmas. Even Newtonian gravity was replaced when time arose for that. You didn't get a schism in form of a Newtonian Church splitting off.
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