The rule could be anything, as funny or as serious as you want. The universe will progress in a similar way that it has up until this point, unless your changed rule prevented it from doing so.
Some examples might be:
- The invention of currency is not allowed.
- Iron is slightly less stable.
- The Ancient Greeks are able to cultivate Silphium, which does not go extinct now.
Honestly, i may be the most hardcore atheist, but it would be sweet if there was a God. You could know good and evil for sure, everyone gets what they deserve even if it’s only in the afterlife, everything has a purpose…
I think it is objectively true that nature is chaos, we emerge from nature, and everything we believe in (currency, nations, laws, good and evil) are just social convention; all of that is the truth, and adapting to the truth helps me live a better life and make better decisions. But it’s hard. It takes mental effort to accept that you’re not the center of the universe and it’s a disappointing thing to learn. I’m tired and i want someone to hand me meaning and purpose on a silver platter.
I personally think meaning is simply about cooperation. Pop-sci video explaining basically what I mean better than I probably could.