They are proof of the uncertainty heaven aspirants have.
No one needs a book called cheese is for real. We know cheese exists.
If enough people become certain heaven does not exist the narrative loses its force and exists no longer. Just as whatever ancient cultures formerly believed seemed plausible in the moment, you now know it isn’t true. You know it in your heart. And you know it’s not worthwhile to keep an open mind over whether the majority culture in ancient Egypt ultimately had it right about the ultimate nature of existence and the afterlife…