Belief System Tolerance: Can it exist?

[Phatose]

A religion, if fully adhered to, would be a belief system. But I'm using the term not just to avoid calling out the religious folks, but because I think even a personal code of ethics is a belief system which makes claims about being right.

Anyway, if you accept 25% of a belief system, doesn't that just shrink the belief system down? If you discard 75% of any system, don't you still have 25% where it's basically right? Just a smaller, more personal belief system? You'll have less overlap, I suppose, which is nice, but I suspect just tossing out 75% leaves you in a position where you now have to defend why you tossed out that part and not the rest, and then you're just making another, different claim about what a valid way to obtain knowledge is.

Worse, what do you do with the areas covered by the 75% part you tossed out? You don't have any guidelines to follow now, so you either need new ones, or you can't do anything

I suppose it can as long as the belief system does not require non-believers to comply with either the views or the rules of behaviour (or both) of believers. In practice, many belief systems share a lot of basic rules of behaviour and can therefore exist alongside each other (and enrich one another).

That's true I suppose. Seems it would be real hard, if not impossible to build a society that way though.

So, maybe tolerance is possible, but only if you're willing to divorce much of the usefulness from the belief system?