# How could a civilization stay at a medieval tech level for millions of years?

My world has a medieval level civilization that has remained unchanged for millions of years.

They look and act a lot like humans; they have language, culture, government, literature, and basic tech.

But, their civilization has remained essentially the same for millions of years. No new tech, no major changes in people’s way of life. Culture does change, and so does language. Countries still go to war, governments change, still though their civilization is pretty much the same as it was over a million years ago.

How could this be? Is there any physical or cultural traits that could result in this?

Edit: thank you everyone for the interesting responses. I wish I had time to reply to all of them! I am starting to put together a pretty interesting back story for my stagnant civilization.

I think I have everything I need for now though I will probably be coming back soon with some more specific questions about my world. I will be leaving this question open for a few more days before I accept an answer to encourage more discussion.

Thanks again everyone.

• Comments are not for extended discussion; this conversation has been moved to chat. – L.Dutch - Reinstate Monica May 2 '20 at 16:41
• Time line for other pre-human species that have lasted over a million years. humanorigins.si.edu/evidence/… – Justin Thyme the Second May 2 '20 at 17:29
• @Hjan Yet even on earth, our dark ages passed into enlightenment, even with a very dogmatic wide-spread Catholic church, so the presence of the church is not sufficient to guarantee stagnation for millennia. – Justin Thyme the Second May 4 '20 at 13:00

The answer lies in your statement they look and act a lot like humans. The unspoken part of this sentence is obviously going to be some form of ; but they differ from humans in one or more key ways.

Take Neanderthals, our kissing cousins (literally!). Sapiens used to think that Neanderthals were dumb, poor thinkers, uninnovative, culturally and materially stagnant. Although newer thinking on the matter is changing that perspective, this is one place where you might want to throw the spanner in the works.

We also know, intuitively, that necessity is the mother of invention. When life throws you a curve ball, you make lemonade, sit down and enjoy the game.

• To get what you want, you're probably going to want a sophont that's a little dim: doesn't really think outside the box, doesn't take too well to new ideas, and prefers routine and continuity as a matter of constitution. (Cognitive)
• You may want a sophont whose dexterity is somewhat lacking: the opposable thumb may be short or not quite as mobile; tool use and fine, delicate work may be compromised. (Physiological)
• You might want to set them in a world that is quite stable tectonically, volcanically, and climatically. Ice ages and huge volcanic eruptions and meteors and things tend to cause upheaval. Upheavals force life forms to adapt or die. You don't want these people to die, but you don't really want them to adapt quickly or change rapidly either. If you choose to make these people smart & dexterous, then you'll need to hobble them in some way, like denying them a key resource (iron is always a good one), which will hamper their technological progress. (Environmental)
• You'll want them to be naturally communal organisms -- not "hive like" beings, but rather clannish and traditionbound in the sense that when the elders teach the younglings, the younglings accept without question and repeat the same patterns over and over again over countless generations. (Social & Cultural)
• You may also consider going down the longeval / slow reproduction route. Take your standard average Elf. With lifespans into the thousands or myriads of years, you get a completely different mindset. Overall development is much slower: there's no need for quick solutions when the thing that has worked for four hundred thousand years is still working fine today. (Constitutional)
• Thank you for the response. This definitely where I’m likely headed – Alex May 1 '20 at 12:20
• You may also want to cut down on their reproduction rate - a burgeoning population would necessitate a change in culture, lest the death toll rise rapidly from being unable to support so many people. Fewer people, and the need to advance becomes less prominent. – Zibbobz May 1 '20 at 13:23
• But how do you explain the fact that they DID advance to a certain level of technology, then stagnated? Your creatures could not have obtained such a level in the first place, I posit. – Justin Thyme the Second May 1 '20 at 18:52
• @elemtilas My bad. I thought it would be implicit in the question that whatever solution was selected, somehow they had to GET to a feudal society in the first place. Otherwise, the question is moot - they were like pre-humanoid species on earth that went for millions of years without developing past the tool stage. 'Not developing' is a cinch to answer. 'Developing' and then 'not developing' is a completely different scenario. – Justin Thyme the Second May 1 '20 at 23:46
• @Zibbobz, keep in mind that the population size is determined by much more than the reproduction rate. In fact, the industrial revolution marked not only an increase in global human population, but also a decrease in human reproduction rate. – cowlinator May 21 '20 at 1:39

Safehold and Stargate both tried this. Neither worked out, but then, the point of both stories was people trying to overcome the "tech hurdle".

In both instances, you have some sort of strict proscription against technological advance, preferably with something to back it up. Safehold uses a super-advanced network of satellites that drop KEWs on anything that looks like advanced tech. Stargate uses aliens with advanced technology. Safehold was working out a bit better (SG1 was full of civilizations trying to rebel against the Goa'uld) until the protagonist shows up to upset the apple cart, because the religious leaders were supposedly benevolent. In both instances, the religion is bolstered by real, visibly people claiming to be god-like, with the tech to back it up.

• +1 for both examples, but Safehold didn't need the protagonist; s/he just accelerated the pace of change. It was happening, just slowly. (Charis would've been doomed, but development still would have happened.) Over a million years (!) the population would've left the medieval era. Or evolved into something not recognizable as human. – jdunlop May 1 '20 at 16:46
• Safehold was definitely developing without Nimue/Merlin. Whether they would get so far as overthrowing the church and more or less ignoring the proscriptions (to the extent possible; there are still those pesky KEW systems) could be debated, but I suppose at that point they are at least slightly past "medieval". No electricity, though; pretty sure that was one of the things that tripped the KEWs. – Matthew May 1 '20 at 17:12
• These solutions, of course, assume the residents are very aware of advanced technology, they just can't obtain it. – Justin Thyme the Second May 1 '20 at 23:51
• @JustinThymetheSecond, yes and no. They are very aware of "magic" (read: sufficiently advanced technology). It/they would show up and make very sure the plebes were aware. That's why this approach (almost) worked; the plebes knew — from first-hand experience — that the god(s) didn't want them tinkering with "advanced" (if you can call a steam engine "advanced") technology and would be more than happy to show up to express their displeasure in case of any violations. – Matthew May 2 '20 at 0:10
• @Matthew We are at risk of being bumped to chat, so one last idea. It sounds like these people still had curiosity, because they had the will to advance and invent, it is just that it was suppressed. That fits. Once the restrictions were lifted, curiosity could take over. Also, it reads like the religion was not spiritual in nature but a tool for power and dominance. There is a difference between religion as philosophical explanation for the unexplainable and religion as means of power. God, Prophet, Pope, King, Pharaoh, President, Dictator, same thing - all mean 'supreme non-elected ruler'. – Justin Thyme the Second May 3 '20 at 3:12

There is only one guaranteed way: it's forced upon your society

Technological advance is the result of problem solving. Your society reached its present level of technology (a considerable amount of technology, if you think about it) by encountering an unconscionable number of problems and solving them. Not the least of which is Mother Nature. Allow me to indulge in quoting one of my favorite actors, and this is the fourth time I've cited this same quote in answers on this site.

From War of the Worlds (2005) we hear the indomitable Morgan Freeman intone the phrase:

From the moment the invaders arrived, breathed our air, ate, and drank, they were doomed. They were undone, destroyed, after all of man's weapons and devices had failed, by the tiniest creatures that God in His wisdom had put upon this Earth. By the toll of a billion deaths Man had earned his immunity, his right to survive among this planet's infinite organisms. And that right is ours against all challengers, for neither do men live, or die, in vain. (Source, sorry for the lousy audio)

Why is this important? Because people (including your people) keep getting sick. It isn't simply random evolution that protects us from illness,1 it's also the people's efforts to save their loved ones. The curious, the clever, the ones who keep chewing on the next root or leaf in the hope that it will, somehow, save their child.

Now reflect that sense of desperation onto engineering problems ("dang river's in the way, sir!"), political problems ("dang pretender's in the way, sir!"), religious problems ("dang devil made me do it, sir!"), logistical problems ("too many dang mouths to feed, sir!") and you'll quickly discover that the only "natural" way to retard technological development is to remove all the problems.

• No sorrow — and no happiness.
• No illness — and no death (neither accidental nor natural).
• No crisis — and no celebration.

Hopefully, this is starting to sink in. The first time one of your feudal lords demands a party that's bigger than last year's, you have a problem to solve — and that will lead to (however minor) technological development.

Which means the only solution is that it's being forced

And I upvoted Matthew's answer, because he's pointing out that you need to force the status quo.

• Clever people must be burned as witches removed from society at all costs.
• Population control must be a paramount requirement, which means some form of child sacrifice some form of medieval contraception is required. It can't be war, necessity is the mother of invention and there are few necessities more demanding and motivating than not losing a war. It also can't bring sorrow, because the pain of losing a child is a remarkable motivator for change.
• Population contentment is almost as important, which means making sure everyone has a chicken in their pot all basic needs are met. (You should be thinking, "post-scarcity civilization in a medieval era... uh-huh....")
• Exploration must be mercilessly quashed devalued whenever possible (M. Night Shyamalan's The Village comes to mind).
• War must be replaced with the Hunger Games must be diverted to some form of entertainment so that its consequences are minimized. In fact, you really need "war" to become something that appeases the masses ("gladiatorial games") without creating need or want.
• All economies must be controlled by the Illuminati must be strictly monitored to ensure no one ever has too much or too little.

And despite this (and a thousand other things) Mother Nature will still cause illness, still bring storms, still afflict with Earthquakes.... Can you see the problem?

A body at rest will remain at rest, and a body in motion will remain in motion unless it is acted upon by an external force.

Life is absolutely full of external forces, leading to problem solving, leading to technological development. You need an overwhelming overriding force that diverts all those external forces such that there's no reason for the vector of your world's lives to ever change.

In a word, you need the Goa'uld.

1Although evolution has a lot to do with it. We've all but eradicated polio, measles, etc. through vaccination—but that technology came at the expense of hundreds of millions dying from those diseases. And if you're not thinking about the Coronavirus right now, you're not paying nearly enough attention. If we actually develop a vaccine before the deaths of so many, it will be the first time in human history that technology came before the price paid for natural immunity. As the "ancient Chinese curse" suggests: we certainly live in interesting times.

• The rate of technological innovation in the stone age was a lot slower than in modern times. Ancient humanoid ancestors lived for hundreds of thousands of years without much in the way of technological advancement. So it is possible, but I think your point is well made concerning the medieval setting. – Slarty May 1 '20 at 9:31
• The Songs of a Distant Earth series plays heavily on forcing society to remain dumb, though it’s got a much less in-your-face way of doing it. – Joe Bloggs May 1 '20 at 9:54
• It is definitely beginning to set in just how difficult medieval tech is to maintain. This is a very dark and interesting scenario however. I could turn this setting into a sort of medieval 1984 state with a lot of work or drastically reduce the technology – Alex May 1 '20 at 12:26
• "And I upvoted Matthew's answer" ...and I upvoted yours. I covered the "how", you covered the "why". 😃 – Matthew May 1 '20 at 14:53
• +1 for your description of the various types of problems. – sharur May 1 '20 at 16:04

# Resources, population, communication

Resources is a cheap trick. They're not going to get much beyond the bronze age if they have no iron. However you want them in medieval which is well into the iron age. You could limit coal. Coal however isn't required for industrialisation, it can be done with charcoal. The trouble being you can't mass industrialise on charcoal as you rapidly run out of trees. Would localised industrialisation suit you? Having an entire planet on a single tech level isn't realistic anyway. Civilisations rise, they industrialise, they run out of trees and they fall again. The thing to remember is that technology is not a stable thing, it goes up and down, when our current empires fall it's reasonable to assume that the technology level will crash just as it did after the Romans, and it will take an equivalent period to recover again.

Population is a good one here, if the population isn't high enough there is neither the requirement nor the labour to industrialise. At what technology level does a civilisation sit without population pressure? One could suggest it stagnates around tribal. A man has a wife, children, a house he built himself, and cows, there's no reason to have or want anything more, there aren't the pressures for it. However that's not your target, medieval technology requires many of the same things modern technology does. It needs space and slack to have great architecture, it needs available labour to build these things, it needs specialised craftsmen to manufacture armour, weapons, castles. Most importantly it requires surplus production.

Communication is important. One of the key technologies that led from the medieval period into the rennaisance was the printing press. The opening up of mass communication. If you can find some way to prevent printing, you might be able to prevent the rennaisance and keep everyone medieval. However printing is an idea that's easy to put into practice. There are some key metallurgy advances that make it easier to develop, but it's going to be really hard to prevent.

# Enforced migration

A wildcard option, crazy tides or seasons perhaps. Something that forces the entire population to keep moving on a steady basis, preventing the infrastructure required for significant technological advance. This way you can almost have a rennaisance, in terms of art and printing at least, regular flooding and perennially soft ground could prevent large scale architecture meaning that things like blast furnaces could never be built (also no castles), big trees are rare, etc etc. Large numbers of different environmental effects aimed at preventing the people from settling and hence preventing major technological development.

• The Chinese had a form of printing press centuries before Europe did. Their problem, however, was the shear number of elements in the Chinese language they had to replicate. The printing press was only practical because of the limited number of characters in Western alphabets. – Justin Thyme the Second May 1 '20 at 23:57
• the printing press was not a big deal in western civilization the intention of castable type was, all of a sudden moving block printing was cheap instead of hellishly expensive. becasue you did not need to create each letter by hand. – John May 2 '20 at 13:47
• @JustinThymetheSecond: Europe had printing presses centuries before Gutenberg. As John said, the big invention of Gutenberg was the process of casting as many individual letters as need based on one master letter. – AlexP May 2 '20 at 17:58
• @AlexP see ancientpages.com/2014/12/30/…, for instance. Movable type, just like Gutenberg. – Justin Thyme the Second May 2 '20 at 18:07
• @JustinThymetheSecond: That is not just like Gutenberg. The genius of Gutenberg was the invention of the letter mould. A highly skilled professional (a "fount designer") made one master "a", one master "b" and so on. Then, the "fount caster" used the master letters to make casting moulds, and then the casting moulds were used to cast as many copies as needed, using low-skilled labor, and sold them by weight to typographers. This is what made cost-effective typography possible. (For this to work, he had to invent the lead-antimony alloy, and the special greasy ink, and so on.) – AlexP May 2 '20 at 19:51

Lack of Resources

They cannot have gas lighting or heating since there are no natural gas deposits.

They cannot have the steam engine since there are no large coal deposits to power the engine.

They cannot have electronics since there is not enough copper for wires or gold for electric contacts.

The difficult part is leaving enough resources to allow medieval technology. For example lack of coal will make blacksmithing harder.

They can of course create charcoal for their forges, but why not just use charcoal to power their steam engines? I'd believe it's a matter of efficiency -- it's not just a case of making charcoal to power the steam engine. It's a case of creating charcoal to construct the entire thing -- an all the hundreds of prototypes before you have a working engine.

The Amish essentially decided that all innovation from the point their community started was undesirable. All innovation works to some extent to make people's lives easier, and they decided this should not happen. Obviously I'm paraphrasing somewhat, but I believe not excessively.

In our world, the Amish are a tiny minority. If in your world there is One True Religion (e.g. the Catholic Church in Europe for roughly a thousand years) and that One True Religion decides to set that as a tenet of the religion, the majority will enforce it. External wars will likely still occur, but suppression of innovation will supersede national differences in holy crusades against innovators, in the same way as Crusaders from all countries marched on Jerusalem with a common goal. The innovators will likely have some advantage, of course, but they will always be in the minority.

Since every innovator is ruthlessly eradicated and their knowledge destroyed, innovators never get to build on a previous person's work. The result will be the same inventions coming up over and over, and getting destroyed over and over again. All progress requires "standing on the shoulders of giants", and any "giant" is slaughtered and buried so that never happens.

It's unclear whether this could continue for a million years. However we have claims that the Jewish Torah has been essentially unchanged for 2600 years, so that's a start. Rabbinical doctrine has always been fractured due to Jews being a diaspora here, but a more cohesive majority religion could maintain similar rules on reproducing their holy texts.

• ...in other words, Safehold, just as in my answer. – Matthew May 1 '20 at 14:58
• @Matthew Your answer says Safehold uses a super-advanced network of satellites that drop KEWs on anything that looks like advanced tech. You don't need that though - you just need the religion to be suitably strict on anyone who tries for technology. No one inventor, or even one country, can make enough technological improvement to stop a crusading army. – Graham May 1 '20 at 15:32
• @Graham, I beg to differ. It really depends on the advance being considered. Imagine realising that dysentery can be induced in an invading army with essentially no threat to the home front because you all understand, have the means to, and practice excellent hygiene, whereas the invaders know nothing and helpfully bunch together in large, smelly groups. the only technology required for you to prevail is a suitable water and sanitation system. – Chris the Hairy One May 1 '20 at 15:46
• The Amish are extremely innovative, having developed highly refined methods of agriculture. They just are not vain, and have no interest in personal advancement or glory. – Justin Thyme the Second May 1 '20 at 18:46
• The Amish are already at a technological level that can advance if they were willing. A real solution must be insurmountable no matter how the people feel about things. – EvilSnack May 1 '20 at 20:50

Westworld

Your permanently medieval world is a built thing. The inhabitants might not be Yul Brynner cyborgs, but they are engineered and possibly semisynthetic creatures as is their society. The entire thing is built for permanence. Maybe every 400 years it loops.

There may be other such worlds.

You can try stopping cultural progress from the inside, basically making your sophonts stupid from a human's point of view, but this raises the question of how did they arrive at a medieval level at all.

It is not possible to stop for millions of years an Industrial Revolution by removing any easily reachable iron ore, since both iron and coal will be supplied by the biosphere (the latter from wood, the former as bog iron - and you cannot realistically remove iron ions from the ecosphere).

Those timescales require preventing biological evolution first of all.

So that is a possibility: your sophonts are actually biological robots, populating a medioeval worldscene for purposes unknown (maybe they were set up by an elder race and then forgotten or abandoned).

Barring that, you need to prevent evolution (see above) and also stop cultural evolution.

This has been done by David Weber (twice: in Empire from the Ashes on the planet Pardal, and in the Safehold series), Star Trek (Gordon Eklund's World without Stars and Joe Haldeman's World without End), in the Stargate series.

Both Stargate and Weber have an alien race capable of catastrophically reverting technology to prehistory (the Achuultani much more so), but that's not what you're after, I suppose.

Weber posits an anti-progressive religion (Pardal), reinforced by strike satellites (the Rakurai overwatch) since otherwise it's pretty clear that greed and connivance will more or less quickly lead to the Proscriptions being flouted. More or less the same thing happens in both ST::TOS Worlds, where a central entity has control over the whole "planet". Haldeman's people are actually more similar to programmed, organic robots.

In this case you need to solve the problem of maintenance for the controlling satellite network. Even the Giskard planetary mind-control satellites in the latest Foundation additions wear out over time, and once they're gone, progress will resume.

• Ah, I forgot about Pardal. (Silly of me, since the entire Safehold series is basically Pardal rehashed. Then again, the Pardal campaign is basically rehashed in Empire of Man, as well.) BTW, both Empire from the Ashes and Empire of Man are great reads. – Matthew May 1 '20 at 19:43
• Up vote for your realization that, as long as there is a will, then millions of years is sufficient time to replenish resources. That is how we got them in the first place. It is the WILL to advance that has to be stopped, somehow, not the ABILITY. – Justin Thyme the Second May 2 '20 at 0:22

## Eloi

Your civilization is being taken care of by another civilization, and has no need to advance.

H.G. Wells figured out a plausible mechanism in his novel The Time Machine. There are two civilizations. The Eloi have everything they need provided to them, by the unseen Morlocks. The Morlocks are able to control the Eloi enough that the latter never advance in technology.

A zoo is a similar idea, in a more benevolent way.

There is no exploitable iron available to them.

One possible reason for this:

Way, way, back, the planet of the setting was home to an advanced race that discovered (by some hand-wavy means) a means to convert iron into energy (like unto the Nevians in Doc Smith's Triplanetary). They soon stripped the crust of all exploitable traces of this mineral.

This society then collapsed or ascended. They are no longer on the scene.

The society that is now in place has reached their own Bronze Age. Bronze is good for many things, but it isn't strong enough, and copper isn't plentiful enough, for it to constitute the infrastructure of an industrial economy.

So they're stuck. They may certainly have many of the cultural achievements of Iron Age and the Industrial Era (literature, music, sculpture, stand-up comedy, etc.), but from a technological viewpoint they can progress no further.

Instincts are real, and the last I heard we didn't understand them much at all.

An orphan beaver can build a log dam from scratch, without ever seeing one before. It just knows how. Instinct.

If you could somehow get a human-like organism that has the instincts to build a medieval society, they will do just that. They won't keep changing it around because they aren't doing things by trial and error. They just know the right way to do things.

I don't know how that could get set up. But if it got set up millions of years ago, you don't have to know how it happened. Nobody knows. The people who're doing it by instinct sure don't know.

You help a woman bake bread. You think you see a better way to do your part, and you start to do it that way. She raps your knuckles with her wooden spoon. "Not like that. This is the right way."

You figure out a better shape for the wooden spoon. You make one and give it to her. She uses it. It clearly works better. One of her neighbors comes by and remarks on it. "Oh, the offworlder made it. He doesn't know how. But it works well enough, so I'll use it until it breaks and then Jaf will make one the right way."

They all pity you because you just don't know the right way to do anything and you keep trying but never get it right. Sometimes you kind of get it after you watch people, but you never know how until you are shown. Pathetic.

• These people's understanding of tool use is less evolved than some primates if they use the lessor spoon out of spite. Humanoid maybe, but not very human-like. I've been working with my hands for 30y and I'm always looking for new ways to not rap my knuckles because I don't shelter a preconceived cognitive bias. Which I guess was your point... +1 – Mazura May 2 '20 at 2:33
• Does that mean they had a feudal society from the get-go, no development necessary? When a beaver builds a dam from instinct, the first dam that the first beaver built must have been built very much like every subsequent dam. Instinct does not get progressively better with each subsequent generation. – Justin Thyme the Second May 2 '20 at 3:17
• Thank you! This is exactly the direction I’m leaning towards. I’m just unsure about how to keep them from feeling too alien. I still want my story to feel like it’s about humans even though they don’t advance. – Alex May 2 '20 at 9:35
• @Mazura, it appears that animals develop instincts after they have been useful for a long time. Kittens that are taken from their mothers young still chase targets, and at a certain age start to stay still while the target moves and only jump toward it when it moves behind something and it can't "see" them. I don't understand how instincts develop and I have no idea how we'd get instincts for a whole medieval technology. Just, if it somehow happened it could explain the story background. – J Thomas May 2 '20 at 10:42

If you are looking for a willful solution, that is, one that was not imposed on the society that would otherwise advance if left alone by some outside sentient force or religion, I was thinking how much these people are alike to humans who had frontal lobotomies. They could think, go about their daily activities, and understand the world around them, but they lacked curiosity, motivation and ambition to investigate the world around them and to plan, hypothesize, or retain new information necessary for advancement. They were content to live their lives as they were. Some even referred to them as zombies.

So how about a 'religious' practice, something like circumcision, that was universally applied to babies or infants, that lobotomized them? It would certainly make for a very compliant, obedient, calm society.

Alternatively, a virus that was highly infectious, that worked only on the brain, to achieve a similar effect? If the virus mutated and evolved when they reached the feudal state, they would be locked into it as long as the virus was in circulation. Something that worked on the dopamine system, maybe, but had no other detrimental health effects. Even if they got immunity after they caught the virus, and the body's immune system dealt with it, the mental or cognitive damage would be irreversible.

I am thinking about the recent research that suggests some forms of dementia are actually caused by viral infection. Syphilis, for instance.

Alternately, an environmental toxin, either biological or poison, that had a similar effect. Something in their diet, or something that was introduced through volcanic activity, or a mutated insect, bacteria, or such.

A twist to this idea, is that it could be reversible if your plot went in that direction. Humans arrive, and determine the cause, and the cure.

• Hm this is interesting. I’d need to do some more research into lobotomies as I am unsure of the specifics of how well people are able to pick up any new information at all. – Alex May 3 '20 at 2:40
• This could also play into a decent explanation for them reaching medieval tech at all. I’ve been thinking that something, at some point after developing the tech I want they undergo some sort of change physically that prevents them from developing new tech. – Alex May 3 '20 at 2:42
• I suggest that these people do not have to be exactly like humans and the human mind, so 'something like' a lobotomy on an alien mind, for instance. The end result could be slightly different than on humans, but the idea of some procedure that altered their brain just enough to destroy motivation, curiosity, and initiative. It does not have to be medically exact or precise to human physiology, so you can hand-wave away the minor discrepancies with 'their mind is alien, after all, and not exactly like humans'. – Justin Thyme the Second May 3 '20 at 3:18

First, look at this in reverse.

Change the question to 'Why have humans evolved in their technology continuously for 50,000 years?' If you can answer this, then you have some indication of what NOT to do.

It is postulated that humans have advanced technologically because of some genetic 'curiosity gene'. Some innate brain construct that motivates us to search out answers to questions we formulate, to search for 'why?'. Some even link this gene to our search for religion. That is, we have established religions because we want answers to questions that were unanswerable without advanced science. This notion depicts religion as a function of curiosity.

Speculation has it that humans became curious because of the evolution of our neocortex and our language areas. They enabled the ability to symbolically form an hypothesis, the basis for all curiosity.

For sure, pre-cortex, pre-language humanoids and human precursors spent millions of years at the 'tool' stage of technology, able to make and use simple tools, that did not change for millions of years. How, or why, did they advance to making stone tools, but then go no further? Because they weren't curious enough to even ask 'why'. Maybe they used the stone ax to kill the person who was curious enough to develop it in the first place, and from that point on 'habit' dominated, not 'thinking'. I call it the 'splat' factor in evolution - when the first instance of a beneficial mutation gets killed right at the get-go, and is unable to reproduce.

I posit that your answer would be in some evolutionary event in which this 'curiosity drive' area in the brain was somehow altered or eliminated in the population. I might suggest that, somewhere in their development, a genetic mutation in the species produced an extremely strong, aggressive sub-species (race in human terms) but lacked development in the cerebral cortex and language areas (the genetic coding for these regions was lost). This sub-species was able to dominate simply by shear strength and sexual attraction/prowess/aggressiveness. That is, they killed off all of the competition, or at least prevented it from reproducing. This mutation/evolution, I suggest, happened at a time when the society had reached a particular level of technological advancement.

In other words, a sub-race became so ferocious, violent, and aggressive that all of the 'smart' sub=species were eliminated, leading to a stagnation of the species as a whole. That is, they were smart enough to maintain and learn What they had, but not curious enough to have any drive to improve on it. This of course assumes that the population at the time of the change was perhaps in the low millions, and they were consolidated in a small enough area such that there were not diaspora that could become large enough to compete.

Certainly their language would be stagnant, and they would not have a religion in any sense that we have today - a mechanism to explain the unexplainable - as they would have no interest in explaining anything. Any religion that they did have, would be more like a government, designed to control and regulate. There would be, I am sure, no concepts of the afterlife or any other belief in anything else but the immediate, as these philosophical musings are a direct result of curiosity and hypothesis formation.

• This is a pretty cool explanation that does away nicely with the seeming problem of creating a civilization that advances to a medieval era tech and stops developing. My story does however at this point 100% need region so that aspect I will likely not use but it’s an interesting idea nonetheless – Alex May 3 '20 at 2:47
• There are two aspects to religion. One addresses the spiritual need to know about the afterlife, birth, morality, the creation of earth, and other such unknowns, which was driven by curiosity. The other aspect is the control aspect, the dominance and power. Religion was the first form of government before countries. The divine right of kings, the idea of Pharaohs as gods. The two aspects are commonly intermingled and conflated, but they serve separate purposes. You can have religion as the government power but not religion as the philosophical musing, the ultimate answer to existence. – Justin Thyme the Second May 3 '20 at 3:00

Stop evolution, both biological and cultural

Biological evolution, because in millions of years, even a long-lived species like Homo Sapiens will undergo significant evolution. And if the biology changes, the culture will.

Well. Making them really, really, really long-lived will help. 10,000 years until sexual maturity would mean you have 100 generations per million years: You will have evolution, but it won't be very noticeable. However, such a long-lived race will have a very, very hard time keeping up with parasites, which can evolve with reproduction cycles of months, and bacteria have 20 minutes per generation - it's pretty likely that bacterium or virus will wipe out the entire population. Any epidemic that can be spread by mobile species (birds, insects) will sweep the entire world within a year.

Cultural evolution tends to change the world even more rapidly.
Humans learn. Not just from catastrophes but from everything. Because humans are naturally curious. Some people believe it's a neotenic trait: in other mammals, curiosity mostly stops in adult life, because once you are mature you concentrate on creating the next generation. So... let them lose the thrill of discovering or doing something new once they're mature. Any new ideas will be seens as the sweet idiocies of youth, waved away with a friendly laugh - "it's good you are looking into the world, my youngling, it helps you learn all you need to learn, but once you're grown up you won't need to do this anymore".

Now the younglings need to lose their curiosity long before adulthood, because if you let children detect and invent stuff for 10,000 years, they will have enough time to come up with something that works well enough that the adults will use it.

So... three life phases:

• Childhood. Curiosity, you learn everything you need to know, for life. Anything you do not learn now will never be learned.
• Adolescence. You do not reproduce, you simply work. Get the resources together for the last phase. Your bodily fitness must stay up, or reproduction will fail.
• Adulthood. Find a partner, reproduce, help the children grow to adolescence, die.
A quick death after raising your children is important to break cultural transmission chains that span generation: Knowing your grand-parents will create a sense of history and change (which is inevitable since now we're looking back 20,000 years).

It's a pretty difficult construction to pull off. Thinking about a society where almost nobody reproduces, everybody works their asses off to have enough resources just for 10 or 20 years of feeding your children, just to die afterwards, curiosity a long-forgotten trait of a youth that's thousands of years in the past, less than 1% of youths in society, having to hoard resources so you can reproduce (or maybe it's really biological that you need 10,000 years to reproductive maturity, except I don't know how such a species could exist) - and once you have made those childrens, your remaining lifespan is so short you won't see them live their lifes. Very strange, very alien, and not very likely similar to anything medieval.

• The problem with longevity in a culturally advanced species is the capacity of their memory. How does one remember everything that happened in 900 years, let alone 10,000 years? – Justin Thyme the Second May 2 '20 at 0:01
• @JustinThymetheSecond you simply forget, or don't even commit to memory. It's what humans do: Have a rough idea of what happened in the last few month, with memory getting less and less reliable as things are older. – toolforger May 5 '20 at 2:45
• So this begs the question be asked, would it be the same 'person', or a continuously 'mutating' being? Like the trope 'Paul Bunion's original ax is in use in a display in the Smithsonian. Since they got it, the head has been changed ten times, the handle has been replaced 15 times, but it is still the original ax.' You would have no idea of who you were, or where you came from, or where you've been, or what you did. Or even of what you knew or what you forgot. You would not be RELATED to an historical figure, you would BE that historical figure, and remember only by reading a history book. – Justin Thyme the Second May 5 '20 at 15:13

## Dragons

What you need is a natural disaster that regularly destroys human kind's attempts to progress their society - Dragons are just the thing to do that.

They're powerful enough to pose a threat to society regularly, reducing the store of livestock and scorching farmlands to prevent overpopulation, and they give humanity a reason to prefer insular scattered communities, as larger cities would be even easier targets for a dragon raid.

With the added bonus of being more medieval in nature themselves, dragons are just enough of a threat to hold back society from advancing.

If you have intelligent dragons, with a slow gestation period and very long lifespans of their own, they may even be doing it on purpose in order to ensure humanity never reaches a point where they could pose a real threat to their continued existence.

But even with dumb dragons, the regular natural disaster they bring to civilization should prevent large cities, big agricultural projects, and slush funds for scientific advances from forming up - preventing your society from making much progress at all.

• Note: I realize this might not be the most practical answer - but I contend with you that it is the most fun. – Zibbobz May 1 '20 at 13:38
• There is more to this than one might think. There have been civilizations on earth that stagnated, because they lived in areas with constant yearly flooding and monsoons that destroyed everything, and every year they had to start all over from scratch. They did not advance very quickly. – Justin Thyme the Second May 2 '20 at 0:05
• This is actually a pretty interesting idea. I could still have the people fundamentally act and think like humans and add an interesting aspect – Alex May 2 '20 at 9:38

A lot of answers here talk about how innovation is intrinsic in humans (and hypothetically other intelligent beings) and thus so is progress. But no-one seems to have mentioned the key underlying part of human progress which is sharing and co-operation. It doesn't matter if you have a genius like Leonardo Da Vinci if everything he knows dies with him. Humans have only progressed so far because we share our knowledge with each other, spread it around and keep having more people improve on it, then share those too.

The things that make this sharing possible are of course language, but especially written language. Medieval periods are obviously times when very few people know how to read or write. You could experiment with there being no written language at all, or it being very clunky and awkward, or learning to read being rare or hard.

But beyond that, the other key impediment to the sharing of knowledge is education. elemtilas touched on this with their suggestion that your people should be

clannish and traditionbound in the sense that when the elders teach the younglings, the younglings accept without question and repeat the same patterns over and over again over countless generations.

How about a better idea? Education is limited to your genetic heirs only.

Someone else mentioned indigenous Australians and other so-called stagnant cultures, and suggested they were stagnant because their needs were met. Not so. Most of the stagnant cultures on earth are in places where survival is extremely difficult. In the case of Australia, the environment is not only so naturally scarce of food that you can't have high population levels, but without frozen winters a key method of food preservation used elsewhere in the world was impossible. Possibly as a result, a culture developed whereby the location and understanding of how to find food/water in an area was secret knowledge.

The ancient Australians didn't have a concept of individual land ownership because they didn't need one - to learn to survive in a new place was extremely unlikely, especially if people already lived there. And if the people who lived there didn't share that knowledge, there was too much risk and not enough benefit trying to do so yourself. People raided each other for resources and to hunt large animals when they were present, people traded, and people were given food when they passed through each others lands, but that was the extent of resource sharing between communities. This seemed to extend to the few places where some level of "farming" or tending existing grains was possible (though the nutritional yield on these is probably paltry compared to even ancient wheat and grains). People just didn't share with outsiders the knowledge of how they survived, and so movement was limited.

Another aspect where this ties into medieval societies is the use of trade guilds. They closely guarded their techniques in a similar way to the Australian cultures, and required membership to gain access.

So theoretically, progress would be severely stunted by a society-wide adherence to only teaching your own children what you know. Combined with a lack of writing, this stops the sharing of knowledge to barely perceptible leaks. Only extremely bright people who actively want to learn something else and have good observation and complex reasoning skills could learn things at a usable level. And if professions were inherited like the knowledge was, even if you learned new things it would be hard to put them into practice. These bright people would have to move to new areas they weren't known to pose as someone who should have that knowledge.

You could either create a quasi-guild system whereby in all places people of the same professions have secret signs to identify each other, or you could create reasons people simply did not move about, as in Australia. Aboriginal knowledge was not limited to genetic children, but it was culturally reinforced quite heavily. This would also be an important factor.

This could solve the "how did they get to this stage" problem. Either they haven't been at this exact level of progress forever but have just been progressing at such a glacially slow pace it seems like it from an individual perspective. OR, they didn't always have a system of guarded or secret knowledge.

You could have some social ramifications from this kind of thing, such as some professions 'ransoming' society to keep producing, but this would require collusion of all their supporting professions that supplied materials. Workers from those professions could always be poached from other communities in that event though. Of course, even other people of the same profession wouldn't know exactly what their fellows knew, because they weren't sharing knowledge between each other like a proper trade guild. So even if a specific individual family develops some innovations, those techniques are only ever known by their heirs. A couple clever generations can be diluted by some dimmer generations who perhaps don't quite "get" what granddad was talking about.

If there was conflict between communities, targeting all the members of a vital profession could be a valid military strategy - another hiccup for the idea, because an entire profession almost dying out would be a possible impetus for breaking the system.

The flow-on to gender roles could also be interesting. My first thought is women would have to taught as well as men, since not everyone is guaranteed sons, and then work at least until they were married. But, to avoid inbreeding, women would have to marry outside immediate family. That might require vast cousin systems for inter-marrying, thus creating "tribe guilds" of professions, and that still creates the chance for knowledge to spread inside that profession, which you'd want to avoid. If women married men of different professions, this creates the opportunity for profession mixing. So in that scenario perhaps women were not taught at all, making their position similar to medieval Europe or even more restricted.

Alternatively, since the whole "not guaranteed sons" thing is still in play, parents could nominate offspring to be their heirs, either male or female, and once they had enough of these (for whatever enough means) any further offspring were not taught. These younger children would be relegated to extremely unskilled labour (think ditch-digging). An heir child could marry a non-heir child without fear of blending knowledge. Though this creates a system of elderborn and youngerborn children almost being castes. (Probably better than "ditchdigger" being an inherited caste like "untouchables" though.) If families help out all their members regardless of task that absorbs any resentment. You might need a bit more society-wide sharing to offset economic needs that would make people break the conventions.

A third option is that there aren't traditional marriages; instead women simply get pregnant by men as they like, then those children are raised in their maternal home. You might develop a slightly matriarchal society like this though, which would look different to medieval Europe. If your males are anything like human males in terms of their sex drive and being extremely competitive for mates, you'd need all the ladies to be pretty sexually active across the board to avoid conflict, and this creates biiig problems for disease in medieval tech levels. So unless STDs are not a thing or you work the high death rates into the social system some how, that might not work out.

There's probably lots more little wrinkles I haven't identified, but the crux of the idea is that when people don't share their knowledge, progress is so limited, so slow, so stunted and easily reversed, that it would barely exist at all. If a culture believes this is the best system (for some reason you would have to invent) and there's no written language for people to even share philosophical and cultural ideas, it would seem to create quite the technological stalemate.

• This is a really compelling way to set up a society, and exactly what i was looking for as far as the cultural aspects of this question. At this point I’m imagining a more dim witted hominid with an already extremely slow rate of innovation. This society develops into a roughly medieval tech level in some pockets, and rapidly undergoes a large cultural/religious revolution that spreads across the entire civilization that leaves them with the cultural traits you mentioned, and an extreme conformist culture. This lasts so long they eventually evolve to be hard wired into their society – Alex May 2 '20 at 9:50
• you do realize Da Vinci went to a lot of effort to prevent other people from learning what he knew, and the real guild structure was focused on keeping methods secret. that did not stop people from having ideas of from other people stealing them. – John May 2 '20 at 13:39
• I think you need to learn more about the aboriginal Australians. They lived along the coastal areas, not in extreme environments. The weather was perfect. They did not even need to practice agriculture - there was an abundance of food that grew naturally. All of their needs were met by hunting-gathering. What they did manage, was effective population control. – Justin Thyme the Second May 2 '20 at 15:56
• So in Martian he could not have done what he did because he was all alone and there was no one to share his accomplishments with? – Justin Thyme the Second May 2 '20 at 16:04
• Some good and valid points. So why did humans get passed the feudal/guild stage? It eventually society out-grew its usefulness when our population reached a critical threshold. Too many over-achievers who did not want to be constrained. It is the human cerebral cortex that is the problem. You have to get rid of that. It is the cerebral cortex that divides pre-humanoids that lived for millions of years in a stagnant culture, from humans who have advanced in just ten thousand years. – Justin Thyme the Second May 2 '20 at 16:21

I'm late to the party and this is just food for thought, but Peter Watts fantastic novel Blindsight posits that technology is always a response to threats or challenges. An environment in which groups are always in competition with each other for resources will push them towards improving offensive and defensive technologies. One where the cold is constant and harsh will prompt developments in heating technology.

An environment where resources are plentiful for the given population -- either because the rate at which the population reproduces and dies makes population growth very slow; the planet is rife with nutrient-dense flora and fauna; or whatever -- wouldn't provide the pressure to invent new and better ways to steal your neighbors' food that we had here.

I'm not necessarily a proponent of the "high technology implies high aggression" theory but it struck me relevant to your question so I wanted to share.

No plagues and Aztec/Chinese style society.

The black plague wiped out almost a quarter of the population of europe and is widely believed to have triggered the renaissance. You had a lot of farmland and not enough farmers, but you still have a reasonably large population to feed. Neccesity is the mother of invention and such innovation in agriculture is neccesary to avoid millions starving. Eventually the population returns to the original levels and agricultural innovations have not been forgotten, allowing more people (potential inventors) to flock to cities and survive off their intellect rather than their strength and eventually one of them will be able to invent a lathe, steam power or any other critical invention for the industrial revolution.

Additionally you can look at the history of china, they had plague and they had great inventors but if not for the "intervention" of western powers it's unlikely they would have industrialised. China's great powers were it's historically massive borders and it's historically massive population. China expanded as far as it could in every direction, even today it goes to the coast in the east, the siberian wastelands in the north, the mountains in the south near nepal, the mountains in the north east near north korea, the incredibly dense jungles of vietnam, the mountainous and desert expanses of afghanistan in the west. They spread as far as they could in every direction until they met a significant geographical barrier (and armed populous). The thing about these geographical barriers is that they usually block from both directions. With the notable exception of the mongolian steppes in the north and the mongolians each of these barriers also protected China from foreign invaders. This is vastly different to europe which had many countries of comparatively small populations constantly invading each other, a place where each country greatest threat was a well equipped and experienced foreign army. China's greatest threat was civil war, essential poorly equipped farmer uprisings against an imperial army.

China's greatest strengths of unity and sheer size were also their greatest weaknesses as it removed the necessity to innovate military technology and tactics and even today military technology is a big driver of further technological innovation.

Other answers have mentioned the fact that the chinese invented the printing press but given their writing system it was almost useless for them due to unique cultural factors.

Why innovate when you dont have enemies and no one is starving?

The Aztecs had cities but not the wheel because they didn't have easily domesticatable beasts of burden (such as oxen and horses) to pull carts, I get the feeling that a "horseless carriage" might be a difficult concept to come up with for a civilisation that lacks horses or carriages, even if they are capable of building cities and making weapons.

How could you innovate when you culturally can't even comprehend the next step?

Look at highly traditional cultures, know your place, don't waste time thinking of new things, follow in your father's footsteps, make literacy difficult (for example by using chinese characters or hieroglyphs), allow polygamy, prima nocta and any thing else that gives people a reason to spend more time attempting to rebel against the system instead of enjoying the collective fruits of everyone's labour.

How can you innovate when there are (starving children in africa!) lords taking all the good women!

Religion, this one is easy and has been covered by other answers pretty well, perhaps you could have a confucian style system where society has been cut into specific classes, farmers, merchants, scholars, artisans, etc... and perhaps add a more modern anti intellectual spin as the scholars don't earn their food, like a farmer or an artisan, nor do they have the wealth of the merchant class but instead must survive as a parasite by the good graces of another. Add this to a romantascism for all things ancient, everything worth inventing has already been made, greek, roman, tang dynasty creations and culture were the pinacle of greatness that we shall never again reach.

To innovate is to spit in the face of our great and long dead ancestors in the name of avoiding a hard day's work.

• Thank you for the historical perspective. This has got me thinking that my word will likely likely have a single Pangea like continent with out much in the way of geographical barriers, and the ones that do exists are so large that people never spread past them. A single culture that looks like China, without easily domesticated pack animals could be a recipe for an extremely stagnant culture – Alex May 2 '20 at 9:57
• @AlexanderTolkan that might actually be an idea animals that can be tamed but not really domesticated, so that every plow animal takes years to train would put some solid constraints on food production. – John May 2 '20 at 13:53
• I'm not convinced that the western way was the only one to modern civilization and that the other civilizations couldn't have made it. The Islamic world had a great scientific culture before the Mongol invasions, China had the Treasure Fleet and who knows what later expeditions could have done to the Chinese culture if the new emperor had been supportive of exploration. The Japanese had begone exploring the seas, but coming in contact with the Europeans shellshocked them into isolation. India is its own highly complex story, it was the industrial center of civilization for centuries. – TheDyingOfLight May 2 '20 at 22:47
• @TheDyingOfLight I completely agree that the western way wasn't the only path, it just happened to be the fastest given the timing of a few critical events. Have you read Guns Germs and Steel by Jared Diamond? It talks a lot about about this most of my answer (besides the china parts) were based on the little I can remember from that book. Do you have any recomendations on books about Indian history? – hamsolo474 - Reinstate Monica May 3 '20 at 11:03
• From an historical perspective, India is an enigma . It just isn't a 'popular' country to study. Can you identify the current Prime Minister of India, for example? I can tell you more about the Hindi religion and its historical evolution than of the people themselves. There does not seem to be an interest in historical archaeology or historical preservation of or even in India. I can not explain it. Maybe it was the British imperialistic occupation and colonization of the country that so thoroughly demoralized it and stole its identity? Maybe a good model for the OP. – Justin Thyme the Second May 3 '20 at 13:56

A planet bound society that endured to many millennia would probably have mined all the easily minable ore on the planet. Which leads me to suggest that they would be very good at recycling (not just metal - everything). All this should lead to stable civilisation(s).

One issue would be "war"; I think you will have to rule it out. War leads to innovation and disruption...

• would probably have mined all the easily minable ore on the planet Or they developed a culture that doesn't use minerals, but renewable resources instead, like wood. – Adrian Colomitchi May 1 '20 at 3:21
• Wouldn't that imply that they developed beyond the feudal stage, then regressed back to it? – Justin Thyme the Second May 1 '20 at 23:47

At some point in their history, a much stronger Toxoplasma Gondii strain evolved and spread though all of the population. In our world, toxoplasmosis symptoms include changes in risk perception*. Infecting with the stronger strain, people just stopped caring about the sort of problems that lead to new technological solutions, and stayed home playing with kittens instead.

*in rats. little evidence exists of systematic human behavioural changes.

A few million years is a pretty long time. Thats basically enough time to go from early hominides like Homo Erectus to modern man. But if you look at that timeframe, you see a very long, slow start and then a rather rapid progress since the neolithic around 5000 BC.

Most of the progress came from population growth, specialization and food surplus allowing it. Before that you mostly had small hunter and gatherer packs, with sometimes surprisingly sophisticated flinstone tools and clear evolution in the sophistication of those tools and even medical procedures. Even long distance trade (thousands of miles) and communication happen, albeit very slowly.

So to slowdown progress to a near halt and stay at a sophisticated medieval level you would need to remove sources of innovation. Get rid of writing or efficient means of communication or teaching. Oral traditions do not scale as well. Make travel very slow, hazardous and low capacity, to slow the spread of ideas as if it was a disease. Make food scarce and surplus production unreliable, so cities have a hard time to feed their specialists and wage war.

Most of this would be pretty hard to do, the only way i could think of would be a contagious plague that was linked to innovation. Like new ideas and challenging the old state of affairs make people deadly sick and contagious. People would isolate themselves in their safe spaces of orthodox thought, innovation would be a real danger and the frequent short and deadly outbreaks in small villages or towns, eradicating the whole place would remind anyone about the dangers.

a lack of metals. If copper and iron are rare you have trouble making tools and machinery. You would even have trouble working stone and wood. It could still be done but it would take much longer. an obsidian ax head would not not work as well as a iron ax to cut wood. Stone would have to be worked by grinding instead chiseling. In theory gold and silver could be used to make electrical and electronic items, but they might be rare too.

• Do you think this would work for millions of years? I’m sure after a period of time even without these elements people would develop some sort of tech even if it doesn’t look like our own – Alex May 3 '20 at 11:42

To see a stable, unchanging civilization you just need to take a look at any of the indigenous primitive cultures that exist in many places on earth. Australia's aboriginals, the Maori, Amazonian tribes, oceanic civilizations , Sub Saharan African tribes, the Inuits/Eskimos of Russia, Canada, nomadic tribes. Many of these civilizations are thousands or even tens of thousands of years old, but have remained mostly unchanged (at least until being introduced to our civilization).

Although their tech level is below medieval, many of them have complex social structures and governments, writing systems, basic money. They don't need to change because they live in very stable environments that they have adapted to. The environments are pretty stable year round so their way of life suits them just fine. They don't need tech or anything else, they heavily rely on tradition and many worship their ancestors, so any innovations or changes would likely be reverted back to their old ways.

• Keeping a society stagnant at a low level of technology is not difficult. The trick is to get it to a feudal stage, and then stop it. If the society was stagnant at the feudal stage for millions of years, did it take them hundreds of millions of years, if not billions of years of very slow development to get to where they were? – Justin Thyme the Second May 2 '20 at 0:09

If they have everything they want, there's no reason why things should change.

Technology only develops where there is a perceived need. If there is no need, and no capitalist system to create artificial needs, then it need not be developed.

Of course society will be very different to any medieval society ever known here, but if there's no disease, hunger, war or want and there is no reason why there should be in your world -- then it can stay in its idyllic condition indefinitely.

Alternatively, other approaches - magic, psi powers etc - might stand in for our technological approach, so you could have, eg, a basically medieval world with street lighting or advanced medicine.

Note that the medieval world spanned centuries, with very different technologies in different areas (Byzantium vs rural Norway), so it's a bit of a moving target.

• So completely get rid of money and any monetary system? Without money, there is no capital for new infrastructure and innovation. – Justin Thyme the Second May 2 '20 at 0:03
• Well, some of cultures which latest longest (like aboriginal Australian) have endured without money, which may be a destabilising factor. – David Hambling May 4 '20 at 8:36
• Certainly without money there would be a very restricted concept of of investment or lending, so financing innovation and research would be very difficult.. – Justin Thyme the Second May 4 '20 at 12:57
• The aim is a society which doesn't have concepts like 'financing', 'research' and 'innovation'. Which would be most cultures in human history. Our current era is a huge anomaly. – David Hambling May 4 '20 at 17:17

George R. R. Martin did exactly this in A Song of Ice and Fire. Westeros (or I guess Planetos)' bonkers weather system was his excuse for keeping society stagnant at a medevial tech level for thousands of years. Wonky magic-driven seasons that last for years mean that society is basically reset every cycle, innovation is a luxury they can't afford, all the smallfolk's efforts go go gathering food just to survive, and potential society changing geniuses are squashed by the need for farmhands (or just die of starvation in winter). This also drives the intensely feudal land system, only the lords have the large castles and large food stores that can survive the winter.

That said, people have pointed out that in this case Westeros' native wildlife should look nothing like Earth because they would have adapted to the weird seasons. You wouldn't get wolves or deer, and the native plants would look more like cacti or baobabs than anything else. And the events of the story do show signs of societal and technological change. So take the effectiveness of that justification with a grain of salt.

I'm not sure if this is the type of answer you are seeking, but how about some characteristics of the planet itself? Maybe an unstable orbit, or an unstable sun emitting solar storms and flares and whatever it is that suns do, wreaking havoc on the planet's climate, magnetic field, and ability to harness energy, etc., causing all manner of difficulty for the populace. Or, the planet is constantly pelted with meteorites or asteroids or other irksome projectiles that screw things up here on earth every so often?

• I think that this answer could be improved a bit if you took some more time to explain how each of these things could affect the population without making it unsuitable for human life/ flat out causing an extinction. Otherwise this does lead my down to a few interesting ideas – Alex May 3 '20 at 2:45
• The problem is that historic evidence strongly indicates that periodic disruptions are a driver of innovation, not a suppressor. The Little Ice Age and the Renaissance/Industrial Revolution, for example, coincided. – Mark May 3 '20 at 5:14
• @Mark I think he means like the 1859: The Carrington Event, which caused telegraph lines to catch fire and a very significant portion of the world's electronics to die at once, but had very little consequence outside of that. If you had events like this every few weeks or perhaps these levels permanently it might hinder the development of electricity. space.com/7224-150-years-worst-solar-storm.html, it's hard to innovate when you don't understand the problem. – hamsolo474 - Reinstate Monica May 3 '20 at 12:35
• @hamsolo474 - Reinstate Monica Up vote for recognizing the difference between 'electricity' and 'electronics'. Electricity is the study of electrical principles for the transmission of power, and electronics is the study of electrical principles for the transmission of data and information. Telegraphy is electronics, power generation is electricity. The difference has nothing to do with the transistor or with computers or solid state. – Justin Thyme the Second May 3 '20 at 14:47
• @hamsolo474-ReinstateMonica, geomagnetic storms only affect long-distance wires. If you keep your electrical systems small (eg. Edison's neighborhood-scale DC rather than Westinghouse's continent-scale AC), they won't be a problem. Long-distance communication is more of an issue, but you can actually build telegraphs to take advantage of the geomagnetism until you're able to build microwave relays or other radio-based systems. – Mark May 3 '20 at 20:46

## Harsh climate, one sex, no prohibition on incest

This is the world of Geten in Ursula Le Guin's The Left Hand of Darkness. Not exactly sure about the incest thing being in the book but threw it in for good measure.

Why: in Earth mammals the males are driven away from their cozy birth environments because incest is genetically disadvantageous. That is so, in its turn, because of binary sexual structure of reproduction.

The males must fend for themselves, must strive to succeed more than other males to prove themselves worthy to be selected for reproduction. This has been the main impetus behind human civilizational progress.

Remove that, add in harsh climate / meager resources so people must cooperate to survive and everyone counts and can't be spared, and you're set.

By the way wars are highly unlikely in such setting. Scurmishes, hardly.

Or maybe go the other way, and have say five sexes, or twelve. Again, incest ceases to be an issue, people stay put and don't make much waves in their lives.

By the way on Earth even with the usual sex structure the societies in the Far North were pretty static until Modernity, I think.

• So behind every good invention is ... sex? – Justin Thyme the Second May 2 '20 at 0:23
• human psychology is determined by evolution. evolution happens through sexual reproduction. without procreation there is no humankind. youthful rebellion is an evolutionary trait to prevent incest. – Will Ness May 2 '20 at 8:17
• I have to admit I just flat out do not agree with the idea that male’s trying to prove themselves to females has been a significant driver of development. – Alex May 3 '20 at 2:50
• Harsh climate is a wonderful driver of innovation. – Mark May 3 '20 at 5:12
• There's an old joke, an old fish sees two young fish and swim's past them and says "Hey guy's, the water is great today isn't it? The two young fish look at each other and say "what's water?". Hes saying that it's hard to see the invisible strings that control and shape your society. I strongly agree that sexual selection has played a massive role in forming core human behaviours and almost all world cultures. In general women like successful men, sometimes that's the man who has the most money, the biggest farm, but sometimes thats the man who is able to profit off solving a societal problem. – hamsolo474 - Reinstate Monica May 3 '20 at 12:24