There have been several threads about magic and tech on this forum, so I thought I'd write a post about it.
So you're writing a story, and it's either fantasy or urban fantasy, and magic and tech coexist. Great. The only problem is, you don't know how to make it work.
Before I begin, I'll assume that you've got a fair idea how your magic system works. If you don't, you'd better sit down and do that before anything else, because you'll never get anywhere without it.
* How long has mankind known about magic? In most fantasy worlds, magic has always existed (I don't recall any series where magic suddenly appeared, though I'm sure someone's done it); in urban fantasy, it leans more toward "hidden world" (magic and magical beings exist, but most people don't know about them) than "alternate history" (Anita Blake) or "open world" (technically The Hollows, though this is more "revealed world"). Again, I don't know of any urban fantasy series where magic suddenly appears/becomes available to a populace that didn't have it before (I think it would make for a fascinating series, but that's a topic for another thread).
* When did people learn to harness it, and how advanced is their knowledge? Was it long ago, before major technological advancements were made, or was it more recently? Obviously, the presence of magic would change the course of history (see DJ Butler's Witchy Eye), but more importantly, it would change the course of technological innovation. Imagine what the Renaissance era would've been like if we'd had planes, or if the Mongols had had firearms, or if something similar to the atomic bomb had been developed during WWI.
* How widespread is magic? Is it available only to those who can afford it, or is it common and cheap enough that everyone benefits from it? Remember: just because you have a magitech setting doesn't mean it has to be "magitech for all". Keeping it in the hands of the elite could make for an interesting setting, too - one where the rich flaunt their wealth and status by showing off how much magitech they have, or where the rich use their power to oppress the masses.
* I would also ask how well your magic system lends itself to integration with technology, but if you're reading this post, you probably don't need to worry about that. Still, it might be a good thing to think about - are there limits to what magic can replicate or replace? More on this in a bit.
When I was researching magitech, I came across an interesting post. It's rather long, but the author summed it up pretty well: "So in a world without pre-existing technology, like one where magic is innate or common, the drive for progress would have to be fundamentally different to make any headway." Basically: if it's easier to do it with magic, there's little incentive to develop other methods. For example, if the people have access to instant communications through crystal balls or mirrors or whatnot, radios and telephones will probably not exist - at least, not the realms that have those magics (see above).
Another way of stating this (I call it the Law of Innovation):
People will use any system that works unless and until something better is developed, or they're forced to find an alternative. The better it works, the less incentive there is to improve upon it.
No matter how well something works, there's usually someone who will try to improve upon it, but in general, innovations still fall under the Law of Diminishing Returns (the point at which the level of profits or benefits gained is less than the amount of money or energy invested).
Innovations are generally developed in this order, from most to least important: basic needs (food, clothing, shelter), labor-saving, transportation/shipping, communication, entertainment, quality of life (things that are not essential to survival, but make life better). Energy sources are also important, but a separate category.
Basic needs goes without saying: if you don't have something to eat, a place to sleep, and some kind of protection from the elements, you're not going to live very long.
Labor-saving devices run the gamut from the lowly plow to construction equipment. Can you use magic to move large, heavy objects, do fine manipulation, alter the structure of objects (refining ore, e.g.), manipulate matter and/or energy (earth-moving, water control, firefighting, electric power, etc.), teleport objects and/or people... the list goes on and on. Just think of your basic labor-saving device and then say "Can I do this better with magic?"
Transportation/shipping go hand-in-hand. From the time we learned to tame animals and use them to haul goods, we've also used them for transportation. Wagons/carts, sleds, boats, trains, cars, planes - nearly any vehicle used to carry passengers can double as cargo transport. The question is, can you make it work better with magic? The Avatar universe is a great example of magic-assisted transportation - the Earth kingdom has Bender-power trolleys and a mail system; the Fire Kingdom uses steamships powered by Fire Benders, and the Water Kingdoms have Water-Benders moving their ships. Teleportation (via spell, gate, or portal) is a quick and efficient means of transport, though as I mentioned above, it might not be available to one and all.
Communication is a big one. As the ability to communicate advanced, people could pass messages back and forth more quickly - news spread faster, rulers could govern their nations more effectively, and innovations and technology leapt forward as people could share their ideas and pool their knowledge more easily. Can magic send messages over long distances (either verbally, telepathically, or through, say, a spirit messenger)? If so, is there a limit to what can be sent (words, images, entire movies, etc.)?
Entertainment goes along with communication, to some degree: radios and TV are a form of both communication and entertainment. Take things a step further, though: What if magic could replace CG/special effects? What about subliminal messages - is mind control a thing? Could it be used to summon creatures (for movies, TV shows, the circus, etc.)? The list here is nearly endless - anything you do for fun could be enhanced with or affected by magic.
Sources of energy have a large impact on quality of life, as well as innovations and how we use them; magic can play a big part in what kind of energy is being used and how. Aside from the obvious elemental manipulation, can magic be used to draw forth, store, and/or transfer energy? For example, did someone invent a device that draws power from the Earth's magnetic field, taps into the heat in the Earth's mantle, uses solar power, or feeds off energy from another dimension entirely? Magic could also make things more energy-efficient (no matter what source they use), or able to use multiple sources of energy.
And finally, we have quality of life. This ranges from the basic stuff like heat and AC for your living space to things classified as luxuries. Are these things more readily available through the use of magic? If alternate energy sources are more readily available, devices that use them would be too (and they would be cheaper).
One final note: I want to include a "miscellaneous" category, for all the oddball stuff magic can do that people don't think about. I've been watching The Gifted, so I try to think about all the things mutants can do that would be helpful, rather than harmful. Telepaths, for instance, can do a lot - help people work through traumatic experiences, interrogate criminals, or communicate with those who can't speak. People with super-strength? No-brainer. Kinetics? Same as magic (see above). Portals, water-breathing, immunity to heat/cold/whatever.... The possibilities are endless - you just have to keep an open mind and take a minute to consider them. Ask yourself: "If I had this ability, what could (or would) I do with it?"
* Lost Kingdom: A blog full of all kinds of fascinating stuff; each post "tackl[es] Magic (as well as issues like the existence of other races, gods which actually exist and interact with the world) as an overlay on top of historical data, which will format the final outcome of each subject." - a must-read for anyone using a high-magic setting.
I'm going to backtrack a bit here. Since I started off with fantasy, I didn't really see a need to worry about technology, so I skipped over that part. Some time after doing the basic world development, though, I asked myself that magical phrase "what if?". In this case, it was "what if the world had more advanced tech before the Sundering, akin to Final Fantasy?" (Refer to this post for more info about the history.)
That got the gears turning. Since I'd already determined that the characters would be travelling a lot, having faster modes of transportation would make things a lot easier. Also, it's been 3000 years since the cataclysm, but records would've survived and people would (eventually) be able to adapt pre-Sundering tech (and really, I wanted to avoid medieval stasis). So, long story short, I ended up with magitech.
The problem was, I had no idea how to do it, so I let it sit for awhile until I was struck by inspiration. Here's how it works:
List several fields of technological innovation, and determine the most advanced innovation (item, process, whatever) in each field. I would stick to commonly available things, unless they have an impact on the story (that new weapon the neighboring kingdom is developing, for example).
My list goes like this:
Agriculture: Crop rotation, irrigation methods, pesticides, biotech; also which crops are cultivated where.
Architecture: Buildings and materials - advances from the arch to the skyscraper, stone blocks to concrete and steel. How are buildings made? If magic exists, is it used to aid construction, or to fortify buildings? Is it slave labor, conscripts, or guild workers?
Communication: Obviously, this covers everything from the telegraph to the telephone, but it also includes things like TV, computers, radio, etc.
Education: Do schools exist, and if so, how advanced are they (primary/secondary/college)? Who can attend them? What subjects do they teach?
Medicine: Procedures and treatments, knowledge in general, hospitals. How advanced is medicine in your world - do people still think sickness is due to an imbalance of the humors and leeches are a good treatment, or do they know more modern techniques?
Science: I know, this is really too broad a category, but you really only need to figure out what's important to the story. This includes physics, chemisty, earth sciences (all the -ologies), metallurgy (especially important if you add new materials!), astronomy, etc. How do people see the world around them? Is science only studied by a few scholars, or is it taught in schools? Is science even a thing, or do people believe alchemy works (maybe it does!) and illness is caused by an imbalance of humors in the body? Where does the knowledge of various sciences lie, vis a vis Earth's timeline of discoveries and inventions?
Transportation (land, air, sea, space): This is a big one. Has the populace advanced past using draft animals, and if so, what do they use to get around? Fun fact: In the Los Angeles valley in the early 1900s, there were plans to make an electric train system for mass transportation; car companies bought out the train companies and shut them down, which forced people to buy cars.
Weaponry: Medieval, modern, futuristic. This will be informed by the type and level of magic - if it's easily incorporated/adapted into weaponry (or replaces it entirely), arms and armor could evolve entirely differently than in our world. Coupled with transportation, this could open a broad field of new innovations.
Once you figure out the greatest advances in each field, decide who has them. If said innovations are possessed/controlled by a single entity or a limited group, figure out the hows and whys (how they got it, and why they're the only ones who have it). It'll usually be something basic like "it's a state secret (nukes)", but a more elaborate explanation ("it was deciphered from a series of carvings in a temple") might spark some ideas that help develop the world further or even kick-start a story.
It takes a lot of effort to keep an innovation secret (see: nukes), and even more to suppress all knowledge entirely (there are almost always rumors, truthful or not). Ironically, the more advanced a culture becomes, the harder it is to hide things from the public due to the presence of mass media, instant communications, and improved methods of spying and bypassing security protocols.
Keep in mind, too, that most innovations are spread through contact with other cultures (through trade, conquest, or espionage) - gunpowder, for example came to Europe from the Orient via the Silk Road.
* The Diffusion of Innovations: "a theory that seeks to explain how, why, and at what rate new ideas and technology spread".
I read a lot, as any person interested in writing should. It's primarily fantasy/urban fantasy, but I read some fiction and sci-fi.; I also like to watch sci-fi TV shows and movies (I like Killjoys and Dark Matter). I've been reading Jean Johnson's Theirs Not to Reason Why series (good read, though the MC is a serious Mary Sue), and something about all the alien races made me think: if you wanted to do non-human races in fantasy, you would do worse than thinking of them of them as "aliens". I also started replaying the Mass Effect trilogy a few months back, and that made me think of something else: fantasy and sci-fi are simply two sides of the same coin.
You probably just rolled your eyes and said "well duh" - it's pretty obvious when you think about it, right? Simply put, sci-fi is fantasy writ large. Observe:
Setting: Fantasy generally takes place on a single world; rarely, it can cover a few different locations on different planes. Sci-fi takes place on anything from a single world to an entire galaxy, and sometimes even multiple galaxies. Instead of hopping on a ship and sailing across the sea to the next continent, you hop on a ship and fly to the next star system.
Races: Both genres range from "humans are the lone race" to "the setting is home to several dozen races". As I mentioned earlier, if you want to make your fantasy races really unique, think of them as aliens. This is especially effective if they originate on a different plane or a continent/location that's never seen humans. Aliens don't think like humans - that's why they're aliens. They have a different set of morals, culture, standards of beauty and bravery and whatever. Sure, they can be like humans, but I think it's be better to start with something far away and adjust them to bring them closer to a human viewpoint, rather than vice versa - that way, you can retain a lot of the "alienness" that makes them unique, instead of making them seem like "humans with pointy ears" (or fur, or sharp teeth, or whatever).
Magic: In fantasy, it's magic. In sci-fi, it's psionics. Either way, it's almost a given that you'll have one or the other. Magic is often genetic and sometimes taught at schools/academies, while psionics is also often genetic, but can also be granted through science (genetic alteration, advanced tech, or some powerful alien being/race) and can also be taught/developed. Magic can exist in a sci-fi setting, but that turns the genre more toward cyberpunk, steampunk, or magitech, which I'll discuss in another post.
Religion/gods: As a rule, gods don't exist in sci-fi. You can, however, have god-like beings - creatures or races who are so far advanced that they're beyond the human ken (Clarke's Third Law takes effect here). Religion is pretty well a constant among all intelligent races, though: if you're self-aware, you tend to wonder where you came from, why you're here, and where you're going, and religion is a good way to explain that.
Civilizations: In general terms, sci-fi and fantasy are nearly identical. A nation is still a nation, an empire is still an empire, you still have governmens and trade and laws and customs... but again, sci-fi does it on a grander scale. A nation in fantasy is equivalent to a planet or star system in sci-fi; an empire that spans a continent in fantasy could span an entire galaxy in sci-fi. Both genres feature lost civilizations, old races that turned to dust long before humans came on the scene, and ancient artifacts whose function and purpose have since been lost to the mists of time.
Want to do something fun? Try converting your favorite sci-fi story to fantasy. Or vice versa. Take Star Wars, for example - it just begs to be made into a fantasy story. The Jedi are an order of martial artists who use ki power instead of the Force. They still fight with swords (which are not lightsabers), but these can vary depending on the user, or maybe Jedi can change the sword's form at will. Their role: let's say they're a group that transcends race and nation and works toward peace and harmony. The Sith, obviously, want to do Bad Stuff (tm) - destabilize governments, take over the world, crush the Jedi, etc. Droids could be replaced with clockwork constructs or just non-human races (depends on the tech level). The Death Star is still a massive engine of destruction, but its appearance and makeup could vary widely - anything from a monstrous sea-going ship to a massive land-bound vehicle to a mobile fortress carried on the backs of 10,000 undead slaves. Planets are turned into cities, the Empire becomes smaller (but no less of an Empire), and the Resistance remains as it is - a ragtag group of people fighting the Empire. Hell, file off the serial numbers, make a few alterations, and you've got a full series right there.
On the flip side, you could take, say, Game of Thrones and make it into a space opera spanning worlds or even star systems. Most it's about war and politics - that stuff is universal. The White Walkers become an interstellar threat looming over all (see Jean Johnson's books). The Faceless Men? Easy - that's just advanced tech. The sorceress (her name escapes me now) would need a little tweaking, but she could be a psionic priestess. Since we're not going for an exact conversion, you can play around with it.
If you write fantasy, one of the things you'll hear (probably over and over) is "magic should have a cost" (or, often, must have a cost). I saw it many times when I was looking at magic systems for my story, and I've seen it plenty of times on this forum too. While I don't necessarily disagree with the sentiment (it makes for an interesting story), it's become something that people parrot without any real comprehension, like "show don't tell", or that whole thing about dialogue tags. (Hint: for the first, it's not that important; for the second, as long as they're used in moderation, it's fine.)
What it all boils down to is "balance" - people think that magic is too powerful on its own, so they want to see a "cost" so that mages can't just up and take over the world, or deus-ex-machina their way out of everything. Of course, if your magic system is designed well enough and the story is written properly, this will never happen, but that's a topic for another post. What I want to discuss, here and now, is the concept of balance.
Which means, basically, that magic should have limitations. Not necessarily a "cost": the word "cost" brings to mind something the caster has to offer or risk to use their magic: sacrifices (blood, flesh, lives), side effects (this one's popular - pain, physical disfigurement, mental issues/brain damage, illness, etc.), death (by various means), backlash (the Wiccan's threefold rule), and on and on.
Limitations, however, are another form of "cost" that many people overlook. Time is a big one - if it takes ten minutes to cast a spell, that's a huge one - magic is severely limited in its use, if not its scope. Having to draw symbols and/or diagrams, chant words, use ingredients, make gestures or a series of movements (like a full-on dance); these are all limitations. Having items that are expended upon casting the spell (not necessarily ingredients, but actual sources of the power) is also a good one. The book Masks had an interesting concept: magic is a physical thing that bubbles up from underground like oil and can be mined or harvested; you have to have some to cast a spell, but once you do, it's gone (obviously, more power = more "magic" used up). If the caster has to make a pact with an otherworld being to gain power, that's a drawback (or a cost, either one) - only those powerful enough and/or crazy enough (depending on the being) will undergo the risk for the potential profit.
Public perception (mages are shunned, reviled, or outright outlawed) is another, though I don't recommend using it on its own unless it's a central part of the story. Similarly, you could use "time to learn magic" - it could take decades to master anything beyond the most basic spells, so very few bother (again, not a great example, but I threw it in here anyway).
A foil - some way that magic can be negated or otherwise circumvented - is also a limitation, though it's better used as a plot device. In the Wheel of Time, for example, Channelers could shield each other, cutting off your opponent from the source of their magic. There was also an herb called forkroot which, when ingested, prevented use of magic for a length of time. In the Avatar TV series, benders could be prevented from using their magic by surrounding them in elements besides their own - drop a firebender in an ice cave, suspend an earthbender in a wooden cage in the air, etc., and they're useless.
Basically, what you're looking for is something that will make your story interesting. Look at your world and your magic system - what makes sense as a limitation, given the world's history and the way magic works? What would make for a good plot and situations where your hero - assuming (s)he's a mage - will have to struggle to proceed, or may even fail outright? Answer those questions, and you're on your way to making a unique magic system.
Since my characters are going to be travelling to various nations, I did some research on coins and currency. Coinage is one of those things that seems really minor, but it's the minor details that more verisimilitude. There's an amazing variance in the kinds of coinage used throughout history. The first coins were created in the 7th and 6th centuries BCE in Greece, India, and China (aka, the earliest civilizations). China even had paper money about a thousand years ago.
Coins can take a surprising number of forms. The most ubiquitous is, of course, the round coin, but we also have square (in modern times, they have rounded edges for vending machines), 8/10/12-sided, and oval (common in the Orient). The edges can be milled, scalloped, or notched, to prevent clipping. Oriental coins often have holes or squares punched out of the middle to permit them to be strung on a lanyard. Coins are always stamped with some sort of design - often it's the likeness of the ruler who commissioned them, or a god/goddess; other common themes are animals, landmarks, or simple designs, often with a legend (writing, often a phrase of some sort).
90% of coins you seen in fantasy novels are copper, silver, gold, and (rarely) platinum. While these were in use in the real world, there were also a variety of other metals used: electrum (a naturally-occurring silver/gold alloy; rare), cupronickel (a copper/nickel alloy, sometimes used to debase silver coins), iron, lead, nickel (used since ancient times), brass (the Romans), and bronze (not that common, surprisingly). Your world could have other materials that are more or less common or valuable. Just keep in mind that we used softer metals for a reason - they're easier to stamp. It just so happens that many of them were also precious metals.
Cultures don't always rely on coinage as currency; many use livestock (chickens, goats, horses, cows), random silver items, https://en.wikipedia.org/wiki/Hacksilver, https://en.wikipedia.org/wiki/Knife_money knives (ancient China), food (salt, cocoa beans, or cheese), or other odd items. Cultures for whom metallurgy is impractical or impossible (undersea races, or those who live in a metal-poor world like Dark Sun) could use tokens of ceramic or bone, or beads of precious/semi-precious gemstones (agate, garnet, jade, pearls, coral, etc.), which could be pierced so as to be strung on a line.
And finally... denominations. Most nations have a base amount (like the Dollar or Euro), which they can then subdivide into smaller units (as coinage) and multiply into larger units (as larger bills or, rarely, also coinage). Coinage typically appears as one or more of the following:
1/100, 1/20, 1/10, 1/5, 1/4, 1/2.
So, for example, you could have the gold Mark as the base currency, then copper (at 1/100 mark), bronze (1/10), silver (1/2), etc. Or you could switch it up and have 20 coppers to the bronze, 15 bronze to the silver, and 3 silver to the gold. It's all up to you.
* Wikipedia entry on coins: A central page where you can check out all the currencies of the world.
* 10 Strange Forms of Ancient Currency: Not all currency was coinage, or even money.
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