The religious mainline cultural institutions are simply too wealthy to disappear in 300 years, especially if they don't pay taxes. I would assume that they will simply adapt with the times as they always have. I could see world where people consider Islam or Catholicism like we see the Amish today, as outsiders.
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
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