Why don't some people understand lack of belief?

[Edwardo Piet]

They probably want to toy with the burden of proof.  If you have a positive claim like "God doesn't exist"  then the BOP is on you.

And yet the funny thing is that is not the case. For the same reason that believing the Flying Spaghetti Monster doesn't exist doesn't require the burden of proof, but believing the Flying Spaghetti Monster does exist does require the burden of proof.

It's a common misconception that "all positive claims" require the BOP (and "positive claim" seems kind of redundant to me. If it's claim at all it's not gonna be a "negative claim"). No... with regards to any claim there is always a claim for the exact opposite, and of the two it is always the claim that is least parsimonious, makes the most assumptions and has the least evidence, that requires the burden of proof.

Now of course, if someone were to say that they are absolutely certain that X claim is true.... then that would require the burden of proof even if the only alternative is less reasonable, because it's not the fact it's a positive claim itself that requires BOP, it's the irrational part about being 100% certain of it when one cannot be. And to suggest that because the only alternative makes even more assumptions or has even less evidence then your own position MUST be true is to commit the fallacy of The Argument From Ignorance.

But if all you're doing is saying you believe X, rather than that you are 100% sure of X, and if the only alternative/the absence of X being true makes far more assumptions, then X is the null hypothesis and doesn't require the burden of proof at all. It's the fact that it already has evidence or is the null hypothesis over the only alternative that precisely makes it not require the burden of proof.

X is true is the null hypothesis if X is untrue is not the null hypothesis. X is true is not the same as X MUST be true. All absolute claims require the burden of proof, yes, unless we're talking claims that are backed up by tautologically true premises.... as to attempt to prove that would just be futile.

To give an example, if it is 49% probable that X exists then there is no burden of proof required on the person who believes that it is 51% probable to believe that X doesn't exist, as that is simply implied. But if the person who should believe that it's 51% likely that X doesn't exist, were to instead assert that X absolutely 100% doesn't exist then yes, the burden of proof would be on them as well. Just as the burden of proof is on the 49% person if they choose to claim it's more than 49%.

---

For some people, it is either black or white.  For them, there is no grey area.

Grey is made from mixtures of black and white

But yeah, there's a great deal in between 0% and 100% probable. But you do either believe something or you don't, and when people say that believing there is no X and not believing that there is X are two different things, I'm not sure what they're talking about. Believing there is no X doesn't imply absolute certainty any more than not believing there is X does, and believing in an absence is the same as not believing in a presence. It's the same damn thing lol.

I have an absence of belief in God, and I also positively, but not absolutely, believe that there is no presence of God... it's the same damn thing. In both cases I am not entirely certain but am reasonably certain based on the improbability of such a god.

Of course, it's possible to not believe in God without being aware of the concept, or even being alive. But so what? The point is that once you are aware of the concept of God and what some people believe in, you're just consciously reacting to that and the belief that there isn't a God precisely reflects the absent belief you had as a baby. It's not like reacting to a proposition consciously suddenly means you have to claim that it's absolutely false or anything else irrational like that.

The only difference is that in one case there's a belief and the other there isn't, but that doesn't matter. The point is the beliefs, when they exist, should be rational, and when they don't exist should be rational. And belief is not the same as claiming knowledge or certainty. Differences that aren't relevant to the matter at hand don't matter to the matter at hand!