Even people who aren’t engineers like me tend to prefer order to disorder. Order is safe, familiar, and it helps the world make sense. Our brains are lazy machines, always looking for opportunities to take computational shortcuts, and order lets those shortcuts remain valid. You may not be the kind of person who has subfolders five levels deep in your email inbox, and you may even think that you hate your daily routine, but your stress levels probably still shoot up when things start going wrong and you’re forced to change from what you expected. The point is: our brains favor predictability and order. The real world, of course, is hardly ever so conveniently neat.
Your fantasy worlds, though: they can be as orderly as you could possibly want to make them. There’s no need to have different languages for different cultures, or measurement systems based on the length of the Prime’s big toe, or different calendars that never quite line up properly. It’s your world, and you’re free to design it in as orderly a fashion as you could desire. But you shouldn’t.
There’s a very fine line to walk in world-building. Go too far one way, and your world starts to become unbelievable (which we talked about in Plausible Impossibility) to the reader. Too far the other way, and your world becomes so complex that the only way to really make sense of it is to live in it for a century or two, and even then you probably won’t understand it all (we touched on this in Building the Learning Curve). Part of walking that line is knowing how to make your world suitably illogical in a logical fashion.
At the heart of this consideration is the simple fact that we live in a chaotic system. The real world, as much as we might wish it to, does not make sense. The systems with which we now live are not the product of concentrated, deliberative design, but rather the result of centuries of chaotic evolution and interaction and competition. We use a calendar system where the months named eight, nine, and ten are actually months ten, eleven, and twelve, because a Roman emperor decided to stick in a few months for himself and his relatives (July = Julius, August = Augustus). We use base ten, but our clocks are still based around sixes, which if I recall correctly is the Sumerians’ fault, because their gods had six digits. There are three hundred and sixty five days in a year, except that every four years there are three hundred and sixty six, because the Earth doesn’t quite revolve around the sun synchronously with its axial rotation. Oh, and there are three hundred and sixty degrees in a circle because early calendars were circular and counted three hundred and sixty days in a year. Have you ever tried to do thermodynamics using imperial units? Talk about logically illogical. Language itself is a prime example of the chaos that has led to the systems we use today. The very existence of jobs like economist are evidence of how complex and chaotic the systems we have created are: we ourselves do not understand everything about the systems in which we live and which we have over the centuries created. And this just scratches the surface.
Since our “real world” is so apparently illogical, a world that does not have a certain illogic to it will not be believable to the reader. It will feel sanitized, forced, and uninteresting, and that will reflect onto the characters and plots that you try to set in such a world. This is perhaps what most separates world-building that is just interesting from world-building that is fantastic. World-building like Sanderson’s Roshar is so compelling not just because it is unique an imaginative, but because he made it chaotic. The way that history has unfolded and been remembered and recorded, and influences the present day, is believable because it’s not all neat and orderly. That chaos and the randomness of it works because it feels real.
One of my biggest concerns as I do world-building for Fo’Fonas is to walk this line. It was perhaps the greatest driving force for me making the religious practices different between Caous and the Rezzixin Empire. It stretches belief enough that there would be a single religion dominant around the world with only small variations that I needed to make more significant differences, no matter how logical an explanation I had for such homogeneity in my head (the tunnels Cersin finds in the second novel are a major hint as to why the world is comparatively homogeneous, so look for that when I finally finish it). I have to be careful talking about this, because there’s a major foundation upon which I’ve built the vast majority of the world-building that I don’t ever intend to confront explicitly. Essentially, there is a reason for the world to have a degree of similarity between far-flung places and peoples that would make an earthly reader skeptical, and perhaps stray too far to one side of the line, but I don’t want the story to become about finding out what that reason is.
Since we as authors are not actually omniscient deities, no matter how much we play with the fates of our characters and move mountain ranges when it’s convenient, we can’t create a world that’s as logically illogical as the real world in which we live. Nor should we want to: such a world would be too complicated for readers to approach in a reasonable novel. This is why even something as beautifully and complexly evolved as Tolkien’s Middle Earth measures things in miles and has Earth months. Make things make too much sense, and the reader won’t believe in the world, but make them make too little sense, no matter how logically illogical, and the reader won’t be able to fully immerse themselves because they’ll be spending too much time thinking about how there are seventeen rotations in Unuron, Kort, and Drev (which was named after the Queen of Calexenia in 2367 benin lomi), but nineteen in Clard and Fortrib, except during every second year of the mongoose, when there are actually twenty three rotations in Fortrib. Oh, and a rotation isn’t a day, it’s the time it takes one of the moons to make a full rotation about its axis and turn its original face back towards the prime meridian again.
Alas, there is no easy trick to achieving the right balance, and some of it will depend on what kind of author you’re trying to be. Brandon Sanderson talks about this a little in his classes, how he has a set of advice that’s directed mostly towards people who are looking to make a successful career out of writing. That paradigm requires different decisions and different priorities than the part-time writer who isn’t trying to make this their main career. Someone like me, who has a day job that isn’t writing science fiction and fantasy, and writes it because I want to be able to share the stories that bounce around in my head, can afford to take more time (and write stories that are less widely digestible) crafting a world in all of its logically illogical complexities. A professional writer who needs to put out a new novel every year or two probably would need to make different decisions.
Even with the luxury of time that I have compared to a professional author, I make trade-offs in my world-building. This is partially to walk that line for my readers between too complicated and too banal. It’s also a matter of how my mind works: for many of the stories, I am much more interested in building a unique history and culture, including odd things like calendars and units of management, rather than spending time building a unique set of flora and fauna in a completely alien ecosystem. One day, I do intend to write something really alien, like on a toroidal world, or a tidally locked planet, but it is partially because of the level of complexity that would take to do well that I have not yet done something of that nature.
I keep talking about logically illogical world-building, and that really is how I think of it. There are so many things in our world that don’t make sense on the surface, but there are explanations, however odd, if you’re willing to dig deeply enough. If there’s a secret to what we’ve talked about here, it’s that: even if you never tell the reader, you should know why you made the world-building decisions that you made. There’s a reason that geometry is a mathematics about shapes, when it literally means “earth measurements” (it’s because the Egyptians invented it to measure out plots of land along the Nile River). It’s a good thing for some of your world-building not to make sense, as long as there are reasons for it.