# How long can knowledge stagnate before it may be deemed 'fantasy'/lost' in folklore?

News media showcase any number of potentially depressing events around the globe - internecine conflicts, ethnic conflicts, catastrophes and what-not.

The corollary constitute fiction as depicted by Arthur Clarke who writes to say

Any sufficiently advanced technology is indistinguishable from magic


Say, civilization is redeemably stripped of two core contemporary technologies - electricity & electronics - abruptly (meaning over a span of a decade). I use the word redeemably here to indicate the technologies mentioned are simply unavailable to the civilization until some unknown future date.

E.g.

• Global ocean levels rise so high as to inundate all ground where a turbine may be installed
• The crew/colonials aboard an interstellar colony ship (as depicted in Heinlein's "Orphans of the Sky") suffer loss of focus

(+: Takes a stretch of imagination, I know)

Some of the consequences may be as follows:

• An equally abrupt fall in life expectancy
• A gradual decline in the quality of education - specifically pertinent to the 'lost' technologies
• A similarly gradual 'return' to provincialism as means to communicate (using the word 'communicate' in it's broad sense to include high-speed long-distance transport as well) disappeared

The second item on the list holds my curiosity. Initially (perhaps upto a generation) there could be some people who would know of electricity/electronics, and also be able to discuss the techniques/technology. Over time I would expect this ball of knowledge to dwindle & stagnate.

How long (read: how many generations) would it be before the knowledge of the 'disused'/'unavailable' technologies were lost out of ignorance as to reduce the technologies to metaphor in folklore?

• Did you mean to say 'redeemably' or 'irredeemably?' Based on the context, I assume the latter. – guildsbounty Mar 16 '15 at 16:52
• @guildsbounty Redeemably (+: Irredeemably would strip the question of meaningfulness. But say a set of conditions were to arise that could herald recovery of the technology. In that case the ability of the civilization/people to carry the apparently worthless knowledge could be key to recovery – Everyone Mar 16 '15 at 16:55
• Okay...then I don't think it would actually be 'lost' at all. If it is redeemably lost, then the people who know of it, as well as the techniques and technology would simply 're-invent' it. It would be like putting out every fire on the planet ('stripping' humanity of fire), then assuming that humans wouldn't just make more fire when they needed it. That's why I assumed 'irredeemably' because that would imply that (for whatever reason...ion storms or something) the technology could not simply be re-established. – guildsbounty Mar 16 '15 at 16:57
• Ah, your edit to your comment cleared that a bit. May want to clarify in your question that 'for some reason, they can't just rebuild it right away.' and that at some point in the future, it may become possible to use it again. – guildsbounty Mar 16 '15 at 16:59
• Wikipedia to the rescue! Sounds like an Asimovian-Foundation question. In almost any situation, there will be small enclaves of people dedicated toward preserving their individual tech... – Isaac Kotlicky Mar 16 '15 at 18:15

Mad Max was based in the "not-too-distant" future, and I think they got it right, in the sense that technologies that prove useful are still in the know-how, such as how to ride a motorcycle or fire guns. Ideas like cities and airplanes were painted as the stuff of legends. Of course, it wasn't specified how long in the future, so we're left with a guess.

Though I would argue that only two generations would be sufficient time to arrive at a point such that Mad Max would have been possible. Most people don't know how to build electronics or get a power plant back online. It would only take a generation to lose all this technical knowledge. It would take only one more for what basic knowledge we have to also become lost, and for only technologies that we need to survive to remain.

This is highly speculative of course, but if you think about it, cities are only able to exist due to existing technology. You would see mass chaos in cities if electricity dropped, and shortly thereafter it would become unsustainable. Cities would quickly become abandoned save for a few scavengers. After two generations, most would have burnt down or it would be absent of anything useful for the taking. Future generations would wonder if it were even possible to have so many people living in such small spaces.

So too would be things we take for granted such as computers, telephones, elevators. All of these things without electricity and without knowing how they work would seem like magic if they somehow could get them to work.

• So ... two generations? Approximately 40 years - assuming procreation occurs at the age of 18 years – Everyone Mar 16 '15 at 17:20
• +1 Agreed. If my parent told me how to troubleshoot a broken computer and I had never seen one operate there is probably no way I could actually fix one on my own given the chance. And an exponentially lower chance for my own child. – Samuel Mar 16 '15 at 17:22
• @Everyone nope. In just 40 years those of the first generation are still living. Forget the term "generation" at all, actually, since it's obviously misleading. – o0'. Mar 16 '15 at 20:42
• @XosMel: Without visualization the ability to relate is degraded too – Everyone Mar 17 '15 at 3:41
• @vsz Cities sustained up to a million before electricity because everything was there to sustain it. The difference today is that we've grown dependent on electricity and electronics in general. That's like saying that we survived fine during the days of 12th century agricultural practices, so we'd survive now with 12th century agricultural practices. We'd produce a lot less than we do today.. mass famine, mass chaos, you name it. At the very least, cities would be the last place you'd want to be for a good long while. – Neil Mar 17 '15 at 8:56

To lose the knowledge of how to make stuff? About a generation. But to have the concepts involved become mythologized? That generally takes around 3 centuries.

HISTORY MUST BE CURVED, for there is a horizon in the affairs of mankind. Beyond this horizon, events pass out of historical consciousness and into myth. Accounts are shortened, complexities sloughed off, analogous figures fused, traditions “abraded into anecdotes.” Real people become culture heroes: archetypical beings performing iconic deeds. (Vansina 1985)

In oral societies this horizon lies typically at eighty years; but historical consciousness endures longer in literate societies, and the horizon may fall as far back as three centuries. Arthur, a late 5th cent. war leader, had become by the time of Charlemagne the subject of an elaborate story cycle. Three centuries later, troubadours had done the same to Charlemagne himself. History had slipped over the horizon and become the stuff of legend.

In AD 778, a Basque war party ambushed the Carolingian rear guard (Annales regni francorum). Forty years later, Einhard, a minister of Charlemagne, mentioned “Roland, prefect of the Breton Marches” among those killed (“Hruodlandus Brittannici limitis praefectus,” Vita karoli magni). But by 1098, Roland had become a “paladin” and the central character, the Basques had become Saracens, and a magic horn and tale of treachery had been added (La chanson de Roland). Compare the parallel fate of a Hopi narrative regarding a Navajo ambush (Vansina, pp. 19-20).

This suggests that 17th century history has for the bulk of the population already become myth. Jamestown is reduced to “Pocahontas,” and Massachusetts boils down to “the First Thanksgiving.” And the story of how heliocentrism replaced geocentrism has become a Genesis Myth, in which a culture-hero performs iconic deeds that affirm the rightness of Our Modern World-view.

The author here is speaking of the "Galileo was persecuted for believing that the Earth goes around the Sun" myth, (the truth is far more complicated, and far more interesting!), but the point raised here has plenty of other applications.

For example, we've all heard the idea that Columbus proved that the world is round. Not only is this so wrong that it falls apart under the simplest possible examination--take a look at a globe sometime and see if you can explain how sailing from Spain west to the Caribbean and then back east to Spain will prove that--he actually wasn't trying to. Everyone knew the world was round already, sailors most of all! (The visual phenomenon of a ship disappearing at the horizon from the bottom up, exactly as it would when moving along a curved surface, has been known since ancient times.) What Columbus tried to prove is that the world was a lot smaller than everyone knew it was--and they were essentially right about the size of the world, BTW--such that if you set out west from Europe, you could reach Asia before running out of provisions. He was wrong about that, and if there hadn't been more unexpected land in the way, he and his crew would have all died at sea.

But in the early 19th century--about 300 years after his fateful voyage--the idea arose, promulgated by Washington Irving, that Columbus was some paragon of Reason, proving to the benighted people of his day that the world was not actually flat as everyone believed, and the myth has stuck around in the popular consciousness ever since.

Therefore, by long historical precedent, if your society reaches a state where knowledge of modern concepts turns into myth, it's likely to take about 300 years.

Almost all knowledge right now is institutional and dispersed.

For example - nobody - not a single person (and to a lesser extent, not a single company) knows how to build a working computer from the ground up.

• The people who refine the metals and materials do not know how to build a chip.
• The people who know how to design semiconductors don't know how to design a CPU.
• The people who design the CPU don't know how to manufacture the CPU.
• The people who manufacture the CPU don't know how to program a general-purpose OS.
• Very few people who design OS's know how to also build a working networking server.
• Etc.

If the internet were somehow destroyed (say, a global catastrophe that eliminated electronic communication for some time) I would guess that the knowledge would be lost within 10-30 years, via atrophying skills and deaths of the greybeards.

• A corollary to this: The more technologically sophisticated a civilisation becomes, the more layered technology becomes and the more diffuse the "big picture" of how it is implemented becomes. Consequently a more advanced civilisation may atrophy faster than a less advanced one. – glenatron Mar 17 '15 at 11:09

In the right scenario it can be very fast. A specialist company, or industry, closes and the methods are lost very quickly as usually the necessary knowledge is not in the hands of a single individual, but in the whole team, and once split, it's gone.

Have a look at the various industrial archaeology projects to see what knowledge folk are trying to re-discover (e.g. how to create the original Sheffield steel)

• Why don't you add a little more about your example of Sheffield steel? – bowlturner Mar 16 '15 at 19:58
• My comment follows on from a programme on the BBC a few years ago where they were studying how the original Sheffield (carbon) steel process was performed, and that at the time they didn't really know how it was made 'back in the day' before they had crucibles and the like. hrionline.ac.uk/matshef/symonds/MSsym.htm shows some of the archaeological digs. I spotted "the struggle of a young apprentice to create something new using the inherited knowledge and experience of generations of Sheffield cutlers is revealed" in the text ;-) – Philip Oakley Mar 16 '15 at 20:37
• content.historicengland.org.uk/images-books/publications/… e.g. section 2.2's comments – Philip Oakley Mar 16 '15 at 20:42
• Didn't a dig in Ebla uncover what were believed to be Leyden Jars, or such? – Everyone Mar 17 '15 at 3:55

It's quite hard to say exactly, because it depends a lot on how advanced the tech is. Bear in mind a lot of artisan crafts were passed on master-apprentice for many generations. Clockwork for example, is hundreds of years old. Steam power, combustion, even the transistor - aren't technically very difficult. So keeping it alive as an artisan craft I think would be very feasible.

However our advanced tech - anything involving a microprocessor - cannot be made without the right infrastructure. So they would pass into history the instant they broke. You'd have the people who had seen or used one - but when they died, then they would pass out of living memory and be one step removed.

A second generation, and that would be that. There might be records, designs etc. but the degree of advanced manufacturing took ... well, the industrial revolution probably started about 1750 - so we've had about a 250 year 'run up' to our advanced manufacturing of today.

Starting over might take less time, because of record keeping. But then, it might not, because people are people, and actually - a lot of our records now wouldn't survive a 250 year downtime.

• A microprocessor may not be feasible to be recreated from scratch but a CPU is certainly doable. Before integrated circuits, CPUs were built out of discrete transistors (even vacuum tubes and electro-mechanical relays way back in WW2). So while you can't quite build laptops, you can build a computer with the power of a 1970s scientific calculator the size of a small house using telephone relays (relays are really simple devices made essentially out or springs and an electromagnet). Google Konrad Zuse – slebetman Mar 17 '15 at 3:34

I'd suggest 3 generations, where a generation is an approximate amount of time for one individual to grow to physical maturity and reproduce. Let's say 20 years, times 3, for 60 years.

I'm saying 3 generations based on the 3rd generation rules for wealth building and space habitats. I know what you're thinking now... huh? These have been referenced before here on worldbuilding (What society might survive the 3 generation rule).

I'd also reference the story "Earth Abides", a post-apocalypse story after a plague decimates humanity. The main protagonist is a geologist. At first, the survivors gather and try to preserve the society they knew. Their children, the next generation, are more focused on building a new society based on the reality they were raised in. This includes no modern medicine, or electricity. They are still being raised with the expectations of the previous generation, which includes a formal education. But there's no use for education in modern manufacturing techniques and the like. They learn what they need to in order to survive.

Their children, in turn, have even less use for what we consider basic education. Reading and writing skills are not commonly held, and much of what we understand of the modern world has been subsumed by nature, and are the stories of the grandparents. The rock hammer wielded by the protagonist becomes a "magical" symbol of authority.