You might be familiar with the two cows method of explanation. I think the origin is a way to explain the differences in political philosophy. You can find a good list at the Illinois Gies College of Business. Here’s an example;
You have two cows. Your lord takes some of the milk.
You have two cows. The government takes them and puts them in a barn with everyone else’s cows. You have to take care of all the cows. The government gives you as much milk as you need.
You have two cows. The government takes both, hires you to take care of them, and sells you the milk.
Robert Wiesehan has a roleplaying game systems alternative of the two cows system. It runs the gamut from D&D, Pathfinder, through Shadowrun and to Fiasco.
Is your favourite system represented? If not; how would you describe it?
Creative Commons cow by Amezzi.