There are generally two kinds of speculative fiction in terms of where those stories take place. One kind takes place in a world that is wholly divorced from our own. In fantasy that means the typical kind of second world story (like, say, The Water Road), but it applies to a lot of science fiction, too. Even if a sci-fi story is told in our reality, if it does so hundreds of years in the future it’s hardly “our world” it’s taking place in.

The second type, of course, takes place in what is basically our current world and universe – at the very least, it looks like what we think our world looks like (before The Year of the Plague, at any rate). Think urban fantasy or any of the numerous examples of near-future sci-fi that dot our pop culture landscape. There’s a particular issue with this, however, something that pops up more often in fantasy and something I first thought about because of a bunch of law professors.

The Volokh Conspiracy is a blog collective of most libertarian law profs and scholars. A few of them are also sci-fi/fantasy geeks, and so talk about that occasionally in and among lengthy posts on the Fourth Amendment and what have you. Several years ago, one blogger talked about having read Lev Grossman’s The Magicians trilogy.

For those not familiar with the books (or the excellent SyFy series that was based on them), the elevator pitch is “Harry Potter, but at college.” With that in mind, the blogger highlights an important difference:

Like the Harry Potter series, Grossman’s world features a hidden society of magicians who wield enormous power yet are unknown to normal humans, whose history they have little effect on. In the Potter series, however, there is a very powerful wizard government that prevents wizards from revealing their powers to Muggles and trying to dominate the world. The magical authorities in Grossman’s world are a lot weaker. It therefore strains credulity to believe that powerful sorcerers have been around for centuries, yet have never revealed themselves to normal humans, seized political power, or had any impact on history.

In other words, the world of The Magicians is different from ours not just in the general sense that “magic exists,” but that people have been trained to use it for generations and are living among us and . . . so what? What major historical catastrophe was averted? What major political movement played out a different way? The answer is nothing, and it’s a bit disappointing.

As I said, the issue has stuck with me. When I read Jonathan Strange and Mister Norrell I really loved the way that magic worked in that book – it was about knowledge, it was about books, not bloodlines and destinies and all that. The relationship between Strange and Norrell reminded me of the apprentice system that trained new lawyers before law schools rose to prominence in the 20th Century. My mind whirred and I came up with an idea for a world, like ours, where magicians organized into firms and did contract work for clients, just like lawyers do, complete with oversight by the state (my main character was going to be the equivalent of a State Bar investigator). “Okay, cool,” I thought, “but how is this world different from ours? After all, if magicians have been operating like this for decades, things should be different, yes?” I’ve foundered on the shoals of that question for years.

This issue raised its head again recently while I was reading N.K. Jemisin’s new novel, The City We Became.

If you’ve read her short story collection you’ll recognize the basic idea from the story “The City Born Great,” which effectively serves as the prologue for this book. Essentially, for reasons that aren’t really all that clear, at some point certain cities are “born” into actual, living entities. Some of these births go well – London, Hong Kong, and Sao Paolo are all living breathing cities at this point – while others don’t make it, or don’t make it for very long – think Atlantis and Pompeii, and New Orleans is having troubles, too. In the book it’s New York City’s turn and its difficult birth in the prologue leads to the avatars of the city (one per borough and an additional one overall) fighting to keep it living.

The book overall is pretty good. Jemisin can lay words on the page like just about nobody else going right now and the individual scenes and chapters are great as set pieces. The broader plot doesn’t quite work, however, and the book winds up feeling like less than the sum of its parts (props here to the audiobook production which, aside from one minor quibble – longer pauses between scenes please! –is brilliant both in production and performance). One reason that’s true is that we’re not given any idea why any of this matters. I mean, there’s a villain to vanquish (in the next book, apparently – grumble, grumble) and a city to save, but as to what makes London and Hong Kong and Sao Paolo different from what New York was prior to its birth we never learn.

On the one hand, this doesn’t necessarily mean the main story suffers. After all, it’s likely that The City We Became didn’t address this issue because it wasn’t really applicable to the story Jemisin set out to tell. Still, one of the great pleasures of speculative fiction is digging into a fully developed world that’s not ours and glossing over such things can leave the experience a little hollow. In other words, if you’re writing modern-world fantasy, or near future sci-fi, it’s worth thinking about what’s going on in the world beyond the discrete story you’re telling. Maybe it’s not that important, but it introduces some interesting possibilities for how to deepen the world you’re building and provide some extra details for readers who are interested in sinking their mental teeth into that kind of thing.