There are a lot of essays I want to write within the field of How D&D Is And Why, but before I even begin, framing it that way has some problems. The concepts and patterns of thought I want to talk about aren’t limited to D&D; they appear throughout tabletop RPG, and even out into books, digital games, movies, and beyond. At the same time, you can play D&D without most of these elements, and many people do. It’s tricky to clearly articulate the idea space.
The reason for this, I think, is because while D&D is theoretically setting-agnostic, from its earliest editions it has incorporated a lot of very particular, and often sort of weird, assumptions about how the game setting works. These assumptions range from the mechanical — e.g., memorized spells forgotten upon use — to the cosmological — e.g., the Inner and Outer Planes. All of those assumptions are technically optional, but they’re incorporated by reference throughout the rest of the game. Abandoning them requires a certain amount of work to follow out all the chains of influence. [This makes those elements a fairly powerful default; people will change elements that are important to the game they want to play, but leave alone elements they just feel neutral about.]
This makes D&D in many ways an inelegant design, but I think that baroqueness was actually an important element of D&D’s success. More cleanly generic RPGs have sometimes struggled to gain traction, because it’s hard to provide a hook for players’ imaginations to grab on to. D&D’s idiosyncrasies are a sort of canonical adventure of setting, a baseline understanding of what RPG worlds look like to fall back on. (In 4th grade, I was accosted by a new classmate who was affronted that the cover of the book I was reading featured a spellcaster wielding a sword. We became best friends.)
For this reason, I think it’s meaningful to talk about a default D&D setting, even though you can’t go buy a boxed set for it. There is an ur-setting that lies behind and ties together all the tens of thousands of campaigns that implement D&D’s setting assumptions, and the scope of its influence makes it useful to talk about. I call it the Implicit Empire.
Its broad familiarity — and frankly, its internal contradictions — makes it wildly generative. Every weird quirk of how D&D does things is a site for exploration, elaboration, or subversion that will be legible to anyone who knows the game. At the same time, the fact that it emerged haphazardly from a gumbo of what a not especially diverse pool of contributors in the late 70s thought was cool means that a lot of those tropes and premises are often real problematic in real deep ways. There’s a lot going on in that tension that I want to explore.