Metaphoric Rules in Role-Playing Games
It is very common for role-playing games to extend rules meant for one thing to cover other fields. The archetypical example of this is using combat rules for other conflicts. This has been the standard way of building rules since Dungeons & Dragons started extending rolls beyond hitting things. First, it was resistance rolls, then skill rolls, when adventuring needed to include things beyond monsters in damp caves. But the overall structure of things remained: you roll a D20 and add some bonus (possibly negative) to see if you succeeded. This is extending the original combat rules beyond the scope they were originally designed for. ...