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.
  • Septimaeus
    5·
    20 days ago

    a moral impetus, informed directly by empathy, that is so overwhelming that the feelings of others are tantamount to one’s own

    I’m guessing this is their meaning. Sounds interesting. Maybe that version of humanity would have far fewer nukes and a lot more good sex.