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.
  • cm0002@lemmy.world
    10·
    4 months ago

    Silphium was recently rediscovered so it’s no longer considered extinct just highly endangered.

    I must eat it now!!!