There's been lots
about Vincent Baker being up to his usual clever self with his diagrams of boxes and clouds and such.
In contrast, I've been up to my usual dumbness in not understanding it very well. So I backed way up and tried to find a good place to start, and I ended up four years ago, here
The one diagram and comment that really helped me understand this thing is this:
"Playing Monopoly, no arrows come rightward out of the fiction. Imagine whatever you want, nobody else cares."Imagine whatever you want, nobody else cares.
In my own dumb way, that's what I was trying to get to with this diagram:
Everyone's got their own little personal SIS. They're imagining whatever they want. Nobody else cares.
So... have I played an RPG like this? Yep, I sure have: D&D 4th Edition. Now, before everyone freaks out, let me assure you that I'm not claiming D&D 4E must
be played like this, or should
be played like this, or anything of the sort. I'm just claiming I've seen it happen. Yes, I know saying this won't help at all.
I should probably throw out an example. Here it is: "I trip the snake. I hit! It's now prone." Things like that happen in 4E all the time. What does it mean within the fiction of the game? Doesn't matter. Imagine whatever you want. Nobody else cares.
There's at least two ways the SIS and the Boxes can relate to each other. "The map is not the territory" and "the map IS the territory."
In the D&D 4E games I've played, the Battlemap IS the SIS. If it's not on the Battlemap, it literally does not mechanically exist.
I should probably give a counter-example too. My counter-example is the games I've played of Spirit of the Century.
The characters are in a location. That location has Aspects, like Dark, or Cramped, or whatever, that carry mechanical weight. "It's Dark, so it's -2 to hit me."
Here's something to think about: How many Aspects does a location have?
The answer: an infinite number. Bounded, to be sure, but literally infinite. The deck of a pirate ship is Dark and Wet and Heaving, but it's also In Earth-Normal Gravity and Earth-Normal Oxygen Atmosphere and Moving Parallel to the Earth's Magnetic Field. In any given instance of play, a few of the infinite Aspects will have an impact on play, and all the rest won't. The map is not the territory, here.
In SotC, it behooves the players on a mechanical level to really Share the SIS. It'd be really hard to play the game without it.
In D&D 4E, there's no mechanical effects associated with the SIS. Share it, or don't; it doesn't matter. Imagine whatever you want. Nobody else cares.
There was a nice bit of discussion in the podcast that was about, essentially, what happens if in the event of SIS Sharing failure. "I take the high ground!" "Uh, there is no high ground." "Say what?" Note that this conversation is entirely plausible with SotC, while it's highly implausible with D&D 4E.
Anyway, that's been my little journey of understanding with respect to this stuff. If it's helped, great. If not, that's okay too.