Think about how drastically our society changed when they added touch screens to phones. How much do you think it would change with the addition of people who can alter the laws of physics with their minds?* We’re talking a lot more than an over-abundance of +1 swords.
1. No Sickness
Curing diseases and healing physical damage is a mainstay of fantasy magic. Mostly it’s used to patch up the protagonist so they can recover from one near-death experience in time for the next one. But if your wizard can heal dragon fire burns or cure magical mummy plague, a little thing like tuberculosis or an infected cut is nothing.
Disease is a major killer of humans, and it used to be a lot worse. Unsanitary conditions* and a poor understanding of germs let sickness run rampant. For most of history, when a person got sick, their only options were to wait it out or appeal to doctors who likely made the problem worse.
Magical healing would change everything, especially if it’s as easy as many fantasy settings make it out to be. Even with modern medicine, some diseases are harder to treat than others. That doesn’t have to be the case with magic. Many magic systems don’t discriminate between HIV and the common cold. Just take a Cure Disease and call the cleric in the morning.
Even spells as basic as D&D’s 0th level Prestidigitation would be incredibly useful. That spell allows you to clean a cubic foot of space every six seconds, vastly reducing the spread of infection, not to mention saving people a lot of work around the house.
Imagine what Europe would look like today without the Black Death wiping out a third of the population. Quality of life would vastly improve, people would live much longer, and they’d be more productive. It’s hard to be productive when you’re dying of a horrific disease or caring for someone who is.
What if the wizards or clerics are selfish jerks who don’t want to give their healing magic to any who need it? Would there be enough Doctors Without Borders types to make a difference? Eventually enough magic users would realize it benefits them to live in a society without people constantly dying of disease. They’d likely charge for their services, and it wouldn’t be perfect, but it would be a lot better than standard medieval life.*
2. Population Explosion
If people aren’t dying of disease, wouldn’t they overtax their food supply and create famine? No, because high magic also means incredible new food production. In some settings, wizards can literally conjure food out of thin air. If they lack that ability, they can use weather manipulation or water spells* to revolutionize irrigation.
Agricultural societies are on a constant quest for more efficient methods of farming. There’s only so much arable land to go around, right? Not when you’re dealing with magic! Using aforementioned weather control and water spells, any scrap of ground with decent sunlight and soil can become farmland. In real life, irrigation is costly and resource intensive. In high magic fantasy, it’s as easy as abra kadabra.
Combined with dramatic declines in disease, more food means more people, which means more wizards, etc. These are the sorts of advancements the real world didn’t see until the Industrial Revolution, and we all know what kind of changes that brought about. Instead of rural peasant villages, most people would live in teeming metropolises like they do today.*
More people also means more strain on the environment, with all that entails. Such worlds would have a difficult time supporting classic fantasy beasts like dragons or giants. That kind of megafauna needs a lot of territory, and there just wouldn’t be room for them in all but the most remote areas. Higher populations would also need more centralized authority, and freelance adventurers would quickly see themselves replaced by state-sponsored monster elimination teams.
3. No Armies
Despite the larger population, armies would get smaller and smaller. The reason? Fireball, and every other spell that lays waste to large areas. In a world of high magic, spearmen and cavalry serve no purpose other than to run down the enemy wizards’ spell slots. That’s not worth the effort it would take to recruit and maintain an army, even if anyone could be convinced/compelled to sign up.
At the same time, wizards are exceptionally mobile. With teleportation or dimension door hopping, they could easily outmaneuver the opposing army and attack its wizards directly. Even as cannon fodder, conventional medieval soldiers would be useless.
With non-magical troops serving no purpose, battles would come down to massive magical duels. The losing side would quickly surrender, because what else are they going to do when all their wizards are dead? Occupation forces might still be necessary for keeping order in conquered territory, but any real fighting would be done through magic.
For that matter, high magic spellcasters have so many options at their disposal, there probably wouldn’t be conventional battles at all. Why go to some field when you can teleport directly into the enemy wizard’s bedroom and disintegrate them?
Alternatively, you could end up with a nuclear situation, where wizards are so powerful that any conflict between them would level civilization as we know it. Either way, men and women with sharp pieces of metal would seem adorably quaint.
4. Wizard Arms Race
In the Cold War, a nation’s status was largely measured by how many nuclear weapons it had. Nowadays that prestige has diminished, but there are still plenty of benefits that come with being nuclear-capable. High magic settings would dial those benefits up to eleven.
Nuclear weapons are only useful for blowing people up, and that was enough to dominate world politics for over 40 years. Magic can do so much more. A nation’s influence and wellbeing would be measured in the amount of magical potential at its disposal. Governments would decry the overproduction of magic, while blatantly increasing their own stockpiles. Maybe they would agree to a ban on above ground magical testing.
This would manifest differently based on the type of magic in question. In settings where magic is a rare, inborn talent, you’d see Hogwarts on steroids. Participation would be free and mandatory. They aren’t going to squander a precious national resource because someone couldn’t pay tuition. Some authoritarian regimes might even have breeding programs to produce better wizards.
If magic comes from a substance, some rare stone or plant, cultivating that substance would be an obsession. Personal wealth would be measured in how much magicanium one had, assuming it wasn’t nationalized. This scenario might see a reduction in benefits to health and food production, with magic being a hoardable resource.
The wizard arms race also presents one of the few situations in which high magic civilizations might come to blows. Normally, there’d be no need for conflict, as the power of sorcery provides everyone a high standard of living. But if one area is rich in magicanium or produces a higher than average number of wizard children, it’s time to throw down. Hotspots in the real world have nothing on the High Sorcerous Planes.
5. Gods On Earth
Any setting with powerful mages is a magocracy, officially or not. The mages might not actually govern, because who wants to deal with tax law, but they have all the power. You really think King Spineless III is going to pass a law that High Wizard Lightning Eyes doesn’t like? Those with supernatural powers would be the ultimate privileged class, their every whim catered to by law and custom.*
But it goes much further than legal authority. In the real world, we worship celebrities who are good at acting or making Youtube videos.* Magic is a lot more spectacular than even the wittiest Joss Whedon movie, and people would flock to it. Particularly powerful or charismatic practitioners could easily form their own cults. After all, who needs abstract gods that may or may not exist when someone right here can control the weather? Traditional religions would fade away or never form at all, until the only gods were wizards powerful enough to claim the title.
Beyond cults and rulership, inequality and discrimination would run rampant. Consider how bad those problems are in a world where most people have roughly equivalent capabilities. Now add a group of people who can alter reality with their minds. It doesn’t paint a pretty picture. In our world, when someone says they deserve better treatment because they’re more capable than others, most of us know they’re full of it. In a high magic setting, they might very well be telling the truth.
6. Technological Acceleration
The end-game of any high magic medieval setting is that it quickly stops being medieval.* At first, it seems that magic would slow technological advancement. Who needs the wheel when we have flying carpets? But necessity is only one reason for technological advances. There hasn’t been a driving need for computers to keep getting faster, other than that people like buying faster computers, yet look at how far we’ve come since the vacuum tube. Technology builds on itself, and magic is just a strange type of technology only certain people can use.
One reason technology used to advance a lot slower than it does now is that you need technology to make technology. Consider, you can’t experiment with gene sequencing until you have the ability to build microscopes. You can’t experiment with new wing designs until you have material light and strong enough to build airplanes.
Magic allows inventors to skip the intro steps. Powerful fire spells unlock the ability to create new metal alloys, and alchemy means a never-ending supply of material to test in the lab. Magic removes the logistical effort of the process, meaning any wizard* could easily become an independent inventor.
New technology brings non-magical people closer to even footing with their wizardly brethren. A sorcerer shooting fire from their hands is a godlike power in a world of swords and axes but less impressive when assault rifles are available. Summoned spirit horses are a lot faster than walking, but they got nothing on the internal combustion engine. This cycle was demonstrated well in the Avatar setting, where benders created new tech that put normal people on the same level.*
When wizards create new technology, they increase everyone else’s ability to contribute. Where once only a sorcerer with strength enhancements could lift heavy construction beams, now a regular worker with a forklift can.* Ironically, this eventually decreases other distortions of a high magic setting. The wizard arms race isn’t so all-consuming when some of the benefits can be duplicated by fusion reactors, and an army of hover tanks poses a problem to even the most badass of battle wizards. Magic is less worthy of worship when people carry supercomputers in their pockets.
Would some wizards try to suppress new technology? Maybe, but it wouldn’t work. More technology benefits wizards too, if not to the same degree, and it only takes a few renegades in secret labs to get things moving.
How many high fantasy settings actually look like a techno wonderland? Not very many, because high fantasy has a very specific aesthetic in mind. But your aesthetic has to fit the story you’re telling. You wouldn’t give knights F15 fighter jets and then still expect them to use lances, right? Magic is the same way. If you want to keep a medieval European-esque setting, make sure the magic is limited or costly enough not to change the world overnight.*
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