How far could civilisation develop within one lifetime - starting from nothing?

Question

This question here asked if it would be possible to reach the moon within a lifetime for a civilisation starting with "nothing". The answer to that question, quite clearly, is: no way.

But it made me think. Given a similar basic experimental setup, how far could a civilisation actually progress within one lifetime? The starting point would obviously be to find food and shelter for as many individuals as possible. In a second step it would be to start investing in primitive technology, making their lives easier and moving up the technology pyramid. How far could they reach?

The basic premise:

• A civilisation of 1 million individuals of perfect health and mixed ages and genders finds themselves in a new world.
• The new world is basically identical to our current world, sans everything human-made: perfect, untouched nature.
• The individuals are distributed in groups over the the surface of a small country/state and know about the rough area where all individuals ended up. (You can assume any favourable climate/region to suit your answer.)
• The individuals are single-minded and peaceful - their only goal is to advance the technology of their civilisation as fast as possible.¹
• The individuals all have constant access to essentially the collective human knowledge of today (this is totally hand-waved). That doesn't mean they also have all the skills though. E.g. every person would know all there is to know about smithing, but would not yet have the trained motor skills or muscle memory.
• One lifetime is (generously) assumed to be 85 years.

Given the setup I'm convinced that the civilisation will reach stone-age technology pretty quickly... But could they surpass bronze- or iron age tech? Early medieval, or even renaissance? What would be the big limiting factors?

What is the highest level of technology that such a civilisation could reach with the given parameters within one lifetime?

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¹ Note, the goal is to have a long-term stable civilisation on as high a tech level as possible, so they'll also worry about educating and raising their offspring, etc.

Answer 1

Not particularly far... The biggest problem was already mentioned, but not in particular detail:

Humans did not only domesticate animals, but also plants. Wheat, rye, etc. as we know them are the product of domestication. In their wild form they weren't particular useful:
The linked wiki-article mentions for example that wild wheat simply shattered and fell to the ground when ripe in contrast to our domesticated wheat, which remains on the stem, enabling it to be harvested en masse.

The process of plant domestication originally was a long and arduous one, because people didn't know exactly what they were doing.
In your case they do, but there is still a lot of coincidence in domestication, since in the end you rely on random mutations to turn out beneficial. How likely it is to turn wild crops into farmable crops within one generation is a question that probably has to be answered by a botanist; what remains however is:
No domesticated crops = no meaningful agriculture = no cities. Great parts of our progress as humans depended on our ability to reduce the amount of workforce necessary to provide essential resources like food etc., enabling the freed up part of the workforce to do other things like artisanship, which usually took place in cities, whose existence was enabled by agriculture.
It doesn't matter if your people have all the knowledge in the world when they are all way too busy gathering food and scattered all over the place. To make use of their knowledge they have to band together in cities and free up as much of their workforce as possible from food production.

Answer 2

Best case: Powered flight. Transistor circuitry. V2 rocket.

Basically 1940s tech, minus the atomic bomb and jet engine.

The most important assumption I've made for this; is they have all of humanities knowledge as of 2020, not just "western white-guy" knowledge. 18th and 19th century European explorers would die in the hostile jungle, right next to local tribes who'd been living entirely in the jungle for generations. All the other answers about "everyone will die in a few weeks" is forgetting about the knowledge of traditional peoples.

If we approach this using the knowledge of western white guys - yeah we'll all die.
If we approach this using all the knowledge of the human race, we'll catch up to about 1820's standards of living in about 20 years.

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What do we start with?

For a million people looking at nothing but empty land the "Giant leap for mankind" moment looks a long way away, but, like I answered on your previous question, the single minded organisation allows us to imply group consent, which shows this is all pre planned in advanced. Because of that preplanning:

• They've landed based on the availability on resources. While a full geological survey probably hasn't been done they know how many people can live in a given region without requiring industrial farming, and have probably distributed around a nice warm continent in such a way that minimal shelter is needed, water is available, and food can be gathered in sufficient quantities year round easily while farms are being set up.
• They have the clothes on their backs and shoes on their feet, nothing else.
• They don't know exactly where minerals are, but they have a good idea from the planning stages about where to look for what based on current geological knowledge, and scatter people near those places too.
• They've preplanned all tasks that need to happen. They've sorted the tech tree and can work on multiple things in parallel.
• They can choose to invest resources in advancement, rather than comfort. They know how to make a TV, but rather than putting resources into mass producing them, instead focused on getting to the next tech level rather than making themselves more comfortable.
• They can optimise their society in a way which prioritises achieving the next milestone over comfort. When there's idle capacity in the workforce comforts can be made, but people should be prioritising building the next achievement over their own quality of life.

Tasks are much faster the second time around

As an example; Edison (and his lab) tried over 3000 variations of the light bulb. Your guys don't need to do that. They have 2020 knowledge allowing them to just choose the right one. So once power and glass blowing and tungsten are available, you can have the incandescent light bulb within days, not years.

Same with the AC motor it took Tesla and Westinghouse 4 years to develop a working AC motor. With 2020 knowledge, once power, copper wires and magnets is available, your guys can build this in a few days, not years.

It was 22 years between the patenting of a transistor in 1926 and a functional device being released in 1948. Much experimentation was done (especially with a war driving demand for radios and such), but it wasn't until Bell labs in 1947 tried an experiment with gold and silicon that we got the first transistors. Your guys can skip those 22 years and as soon as decent silicon is available they can get a prototype transistor.

They know how to refine minerals, and as soon as a forge can be built (needing bellows and clay bricks), can get it right first time. They know how to extrude copper into wire, they know how to make silicon from hot quartz sand, and they know the applications of that in advance. Steel took considerable experimentation to achieve, getting the ratios of carbon to iron right via controlling the carbon dioxide production is non trivial, but your guys know how to build a steel forge as soon as iron, coal, bellows, and bricks are available.

Same with powered flight, tyres, indoor plumbing, textile manufacturing, basically every advance humanity has made had a period of experimentation before it, which you can skip or greatly reduce because you know the answers.

You can fly through the stone age (only needing it for simple mining and tree felling) and will probably have copper or bronze tools partially available before everyone has a house built (climate is real nice, remember). Actually come to think of it why bother having one house per family? They're single minded and devoted to the task - make it one house per group of 20, put them in bunks or even cuddled up together and get some economies of scale with meal prep and child raising.

There are also many advantages 2020 knowledge gives even when absent of stuff. You know first aid, how to lift heavy loads without hurting yourself, sanitation, quarantining sick, you understand project management, engineering, and botany. You understand how to build a mine safely, how to forecast the weather 24 hours out from local observations, how to navigate based on celestial body positions. You know natural medicines and bush tucker. You know wilderness survival tricks.

You know what technologies work out in the end (e.g. windmills) and what doesn't (Alchemy). Your society will fly through the tech tree because it's done it before and knows the way.

A 10 year old girl who landed in the original settlement, dying of old age at 85 in a hospital bed, will see her grandchildren launch a V2 style rocket that leaves the atmosphere. Her child, dying of old age 20 years later, will probably see the moon landing from her hospital bed.

Rough timeline:

Week 1-2

• Travel to prearranged positions around land.
• The land is very fertile (it was chosen this way), and your people know how to find food and water in the wild in transit.
• They travel in large groups, predators are few (remember land was chosen in advance) and those that do exist here are unlikely to attack a large group.

Week 2-5

• 50% go out hunter / gathering.
  • Optimistically, you only need 1 food maker per 3 - 5 people, (or done as per Aboriginal hunting parties of 5, gathering parties of 5, feeding a family of 30). but working on a 1:2 ratio adds a level of safety and to make up for the non-evolution of plants which humanity didn't selectively breed.
• 45% building tools
  • stone axes for land clearing
  • stone picks for mining
  • hoes for land turning
  • better hunting tools.
  • simple woven baskets to aid in food gathering
• 5% exploring pre-identified possible ore deposits.
  • focusing on potential clay, coal, iron, or copper.

Month 2-3:

• 50% go out hunter / gathering.
• 20% exploring pre-identified possible ore deposits.
• 5% mining clay and copper/iron
• 15% cutting down trees, for wood and clearing for farmland.
• 10% build simple huts - shelter from storms now, but mostly for food storage.

Month 4-5:

• 50% go out hunter / gathering.
• 10% exploring pre-identified possible ore deposits.
• 5% making clay pottery:
  • bricks for better forges
  • pottery for food & water storage,
• 5% mining clay and iron/copper
• 5% preparing farmland.
• 10% making simple shelters
• 5% digging kilns into hillsides for simple processing.

Month 6-7:

• 50% go out hunter / gathering.
• 20% preparing farmland.
• 5% mining copper/iron
• 5% making copper/iron tools
• 10% making shelters.
• 10% making replacement clothing.

Month 8-12:

• 50% go out hunter / gathering.
• 30% working farmland.
• 5% mining copper/iron
• 5% making copper/iron tools
• 10% trading with neighbouring colonies - resources in starting colonies are unlikely to be evenly distributed.

Year 2:

• 30% go out hunter / gathering.
• 40% working farmland.
• 10% mining simple resources (copper / coal / iron / sand etc)
• 5% making better tools
• 5% setting up simple refining infrastructure (brick and fire forges), and starting to refine copper, iron, quartz, glass, and other simple things.
• 10% trading with neighbouring colonies

Year 3-8:

• 20% go out hunter / gathering.
• 50% working farmland.
• 10% mining simple resources (copper / coal / iron / sand etc)
• 5% refining simple resources (pure copper, pure iron, glass)
• 5% improving existing tools using refinements
• 5% transporting goods between colonies to make up for local shortages.
• 5% replacing worn clothing, shoes, tools, etc.
• Make Gunpowder (or another similar early explosive), use it to mine faster.

Year 9-13:

• 10% go out hunter / gathering.
• 40% working farmland.
• 15% mining and refining resources
• Join adjacent colonies together into small towns, keeping any productive farms only as farming communities feeding food into the towns.
• Start making mediocre steel (Iron and coal), silicon (Quartz sand), and other similar technologies.
• First magnets, copper wire, and pumps.
• First steam engine.
• otherwise approximate technical parity with the 1810s.

Year 13-20:

• 45% making food from farmland / hunter / gathering.
• 15% mining and refining resources
• First power generation (ideally hydroelectric, but can be coal or wind depending on locale)
• First batteries
• 5% of people involved in trading between 50 towns of ~20,000 people.
• Otherwise Basic technical parity with the 1820s.

Year 21-25:

• Basic electrical parts. Relays and diodes.
• Use power to create aluminium, and other similarly refined things.
• Start casting alumiumium and steel in bulk.
• Basic technical parity with the 1830s.

Year 21-25:

• Spanners, wrenches, and other modern manual tools.
• Sewing machines.
• Vulcanised rubber.
• Long distance telegraph lines.
• Basic technical parity with the 1840s.

Year 26-30:

• Refrigeration
• Railways with steel tracks between towns.
• Basic technical parity with the 1850s.

Year 31-35:

• Telephone connection point-to-point.
• Photography
• Basic technical parity with the 1860s.

Year 36-40:

• AC power generation
• Hydralic / phumatic hand tools
• Basic technical parity with the 1870s.

Year 41-45:

• Two stroke engine
• Telephone exchange.
• Basic technical parity with the 1880s.

Year 46-50:

• Punch card machines
• First Electric car
• First radio
• Basic technical parity with the 1890s.

Year 51-55:

• Vacuum cleaners
• razors
• powered flight
• Basic technical parity with the 1900s.

Year 56-60:

• Power in households
• Electrolysis
• Basic technical parity with the 1910s.

Year 61-65:

• Video transmision.
• Simple rocketry
• Basic technical parity with the 1920s.

Year 66-70:

• Ballpoint pen.
• Cryogenic temperatures
• Basic technical parity with the 1930s.

Year 71-75:

• Transistor.
• Rocket leaving the atmosphere (not orbit)
• Basic technical parity with the 1940s.

Answer 3

Honest assessment:
Your population will be exceedingly lucky if it manages to break ìnto the Stone Age, let alone get out of it, and they will be exceedingly blessed if fewer than a third of them end up dying within the first month.

The fact of the matter is that the setting these people end up in is essentially Earth minus three and a half million years (a time frame in which we can safely remove everything man made). There will be no tilled earth, there will be no domestic animals of any kind, there will be no domestic plants of any kind, there will be no easily obtainable raw materials of any kind. There will be hostile creatures: wolves, cave bears, lions, tigers, bears, and all sorts of creatures that will be looking at one million naked humans suddenly dropped in their territory as basically dinner for the next decade.

Having knowledge of something like a lightbulb or a gun or an antibiotic is one thing. Being able to apply that knowledge in order to get a useful result (a working lightbulb, a functional gun, an antibiotic that will work against the local flora) in quite another. And lastly, doing all three of those things correctly the first time around before the first wave of mass deaths occurs will, again, be nothing short of a miracle.

I challenge one of your basic premises: you say that you've got a million "single minded and peaceful" people. But I ask you to recall what happened back in February or March (2020): a really very minor crisis (COVID) caused social panic resulting in an almost comic post-pockyclyptic response. Supermarkets instantly devoid of the strangest things, like toilet paper and fresh meat within a week and panic buying of just about everything else over the next couple months. I think you either over estimate average people's responses to stressors or else underestimate the environment you're placing them in.

If we look at the situation from first principles, we know one million people will need to drink, they will need to be fed, they will need to obtain shelter; and these will need to be found within the first two days. They can do without clothing in almost any climate as that's a luxury they can't afford to obtain at this time. They have no tools and do not know where any resources are located.

They are basically screwed from this point forward. It's all well and good to plan out a road map to civilisation from the comfort of the 21st century planning room; but for these folks, it's soon going to be night. And the world will suddenly become a very dark, very frightening, very deadly place. They have knowledge, but no skill, no practice, and no teachers; and no amount of theoretical knowledge will prepare them for life in the wilderness. They have no tools and no tools to make tools. They can pick up a couple sticks or a couple stones, and that's about it. However single minded they may have been before, there is now no organisation and no support.

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I think a reasonable timeline would be:

• After the reality sets in, the initial organisation scheme fails as there is no food, no water, no shelter, no clothing, no tools and only a fool's plan for some now obviously unobtainable future. After a couple days of squabbling among the die hard project-first people, pragmatic factions arise and silence the visionaries from the old world. Unsure, most people kind of hang around the places where they first arrived. Maybe they hope that the Planning Team will send along a care package? Hungry and thirsty, individuals and small groups begin to break off from the herd.
• One group of say thirty follows an animal track and manages to find a carcass with some sun baked & blackened bits of tenacious cartilage and tendon still attached and a stream within the first few days of foraging. They've got sticks of varying quality (mostly dead wood that's been subjected to the elements for a season or more). They're starving and thirsty. They can all drink in the stream, but there's not enough left of the carcass for everyone to eat. Still mostly hungry, they hunker down in a clump to sleep. Wolves attack; two humans taken, twenty injured.
• A week later, four of the injured at least seem like they might survive the ordeal. Wolves have taken a few of the other injured. Infection will take the rest. Of the dozen remaining humans, several are feeling sick after gnawing on what was left of the maggot ridden carcass. Others are showing symptoms of dysentery. A small cadre decide that in order to survive, they have to eat something, so they pick the least sickly of injured and thump him with a stone. At least now they can eat something other than rancid carcass and maple leaves. Arguments break out over what just happened and the group splits.
• A fortnight later, two of the women think they're pregnant. One of them has a broken leg. Fortunately, the group, now seven in number having taken in a couple odd fellows who were kicked out of another group, have found shelter in a small culvert and they've spread some fallen limbs over top. The last of the human carcass is now eaten. Attempts at hunting have failed. No success on the fire making front either. The woman with the broken leg is now complaining that she can't breathe.
• A week later, the woman with broken leg has died. The two odd fellows had to be driven off for forcing themselves onto the one remaining woman. A bear has attacked the group. Two of the men are killed and one is severely injured, but at least the bear was driven off.
• A week later, the injured man is dead from blood loss and infection. The sole survivor is the pregnant woman. She's infested will all sorts of parasites and is chronically ill with some kind of bacterial or viral something. She's pretty close to starvation, has no fire and only a couple of clumsily sharpened sticks for defense.

That's about six weeks. On the bright side, she knows all about the Internet! She knows how to make a light bulb and how to fly a plane and how to plant corn and wheat and rice! She knows how to milk a cow and how to herd sheep! She knows how to train a collie to help with the flocks! She knows how to turn a lump of iron into a knife and how to fell a tree and cut it into nicely jointed lumber!

But the wolves are circling again. She and her baby can die tonight having learned that civilisation isn't something that can be brought out of nothing within anything like a short period of time! They can also die in the hopes that, somewhere else in this wide and terrifying country, some other mother and child might survive long enough for some fellow to find a flint and make a fire...

Answer 4

Ultimately this is a question about what it means to have access to all of human knowledge.

You might be interested in The Secret of Our Success How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter by Joseph Henrich (2017).

He starts from the premise that "50 of your co-workers" dropped into the wilderness would fare less well over 2 years than 50 capuchin monkeys.

He also discusses the closest historical, natural experiments to what you're describing: nineteenth-century European explorers consistently dying in regions of the world that indigenous peoples lived in.

So if what you mean by having access to all of human knowledge is a good academic knowledge of western science and tech, then I think the more pessimistic answers above are correct.

But if you mean the knowledge---and the culture needed to value and apply that knowledge---of literally all of humanity, then one can be more optimistic. Our humans will adopt the features of past societies most adapted to the habitats in which they find themselves.

Then the constraints are physical and largely agricultural. It can take a generation for olive trees or vines to become productive, for example, and in the pre-modern world farming was a generational activity. Even during periods of rapid agricultural improvement, it takes about a decade for 1 million people to move off farms: USDA stats

Lastly, such wise, flexible, and knowledgable humans hardly feel typical. I also suspect they would not blindly strive to recreate our history of technology. It's not obvious to me at least that the order in which our world has made its scientific discoveries is the same order one would choose if one could.

In sum, humans capable of recreating our world's technology from scratch in one generation would probably choose to do something better.

PS I think this is the premise for CJ Cherryh's Foreigner series, no?

PPS I'm new to this site, apologies for any faux pas.

Answer 5

I don't think they will reach past the farmers stage. I am not sure they can even reach the metal working stage.

First, they start as 1 million people with plenty of knowledge but not manual expertise nor resources.

For example they know that dumping your own wastes where you get your food or water is a bad idea, they know that a good hygiene is the ground for a good health, but have no way or tools to make soap or dig a sewer. And not having seeds they will have to hunt for food.

Those who do not die of some bacterial infection will face hunger and most likely will starve: again, knowing that you can hunt a deer or a boar with bows and spears is a thing, knowing how to do it is another.

Then those who survive this first stage have to start looking for seeds, and they won't have industrial seed with their high yield, nor anything to work the ground. They will face years of barely passing the winter while struggling to make some improvement on their hygienic conditions and farming equipment, starting from domesticating animals. Until they don't have a horse or a ox to pull the plough they will face harsh times and have almost no time to dedicate to anything else than looking for food.

Answer 6

Cannibalism, Bows, Goats, Wooden Hoes, Pottery and subsistence farming, using some bronze tools

Let's assume our population is one million. And we dump them in the most fertile area of the world, the Nile, without any tools and supplies.

Week 1: The first days are dedicated to trying to scavenge enough food. However, by day 7 our groups have to resort to cannibalism as they work on tools to do more than scavenge the fertile lands of the Nile. Assume 75% of the population die (or are sacrificed) and are eaten. This measure will support the remaining quarter of the population over the first months, allowing them to create stone tools and harvest the first wood with less pressure upon the non-existent food reserves.

Our population is now in the area of the population supportable in the Nile region before the year 4000, though the 4000 BC population of Egypt had about 6000 years to actually create the tools (including crops) and infrastructure (roads, houses) they needed to support themselves over our new arrivals.

Week 2: The remaining quarter has become hunter-gatherers and subside on a diet of antelope and fowl, hunted with simple selfbows created with the stone tools. Over the next week, the rare time not used to rest and hunt is used to create basic shelters for the communities and work on setting up the first attempts at farming. Since the only available crops are wild, the results will be meager and it will take months for them to show any yield at all. Luckily the Nile gives us one of the most fertile non-rainforest grounds with its regular floods - our arrivals don't need to look for fertilizing and revitalizing the ground.

Week 3-Year 10 The attempts of farming lead to the first domesticated grains and vegetables. However, the results are more than meager and can't support the groups yet. If we assume that one pound of einkorn yields 10 to 16 pounds, it will take the yield of the 9th harvest to get above subsistence farming, if they find a single pound of Einkorn. We know it took the 4000 BC Egypt about 25000 acres of land to support their third of a million population, so that is our benchmark what we need. To seed that land you need about 2.5 million pounds of Einkorn wheat. The first yield that could - under perfect conditions - get above this magic number is the year 8 or 9 one, depending on the exact yields and the amount of loss over the winter. So Year 10 will mark the year our people could get bread and will need to build some sort of milling device!

Till this year, the group relies heavily on hunting and creating grasslands to draw grazing animals closer.

Some of the hay yielded by the crops is used to make bricks, allowing the construction of permanent shelters. Clay pottery is becoming an available product. The bows get better by using recurve designs and sinews. Most of the tools are knapped flint attached to the wooden handles with tar.

Year 10 - Year 45 In the next 35 years, the groups managed to domesticate goats (or a similar animal) simply by providing them protection from predators in places they graze so they became somewhat docile. As a result, they let this first, half-wild cattle graze on the outskirts of their tiny settlements, supplying meat and milk. in addition to the wheat. The pinnacle of the available technology at the start of this period is the wooden hoe and the bow.

Because the food situation is somewhat secured due to the availability of grain, first prospection missions can be started, searching for copper or natural bronze. The bronze will allow better woodworking tools and hunting and sickles, allowing to increase the arable fields for the next generations - and ensure that the next generation can start to work on better technology. Also, the group now has to work on creating the next generation - and school them.

Besides domesticating other plants and animals, the mammoth project of these years is to attempt to preserve their knowledge for the next generations. Possibly the bronze tools are used to inscribe sandstone slabs or clay tablets.

Another mammoth project that can be started and possibly completed is connecting the settlements with a rough road network, allowing to transport the bronze tools to the farms, while sending food back to the mining areas. However, mining might still be mostly a seasonal thing, using the high tide season for the workforce.

At the end of year 45, our first generation is getting to the end of their productive life. They had a hard life and spawned a viable second generation. This one now is starting to have kids themselves. Most of the first generation died from complications due to the lack of medicine, quite some of the knowledge they carried now is lost. However, if they set things right, the next generation might be setting their goals straight for iron and steel tools.

Answer 7

Your getting a lot of very pessimistic answers that raise great points, but also Ash's very optimistic answer with great points and a very fast timeline. The answer will surely be between these two extremes, and for evidence of this I'm citing the excellent Primitive Technology series on YouTube. This is one guy in the wilderness with modern knowledge, and he's already flirting with the iron age. Granted, he has the immense advantage of this being a low stakes hobby and being able to return to the modern world once the weekend is over, but it goes to show that if your million people can manage to keep one guy fed and comfortable enough to have free time they can get some great work done.

How far the group gets depends on what the exact nature of having all collective knowledge means. For this answer I'm assuming it goes beyond just Western society knowledge and includes the knowledge all native people have to survive in the environment.

They'll get solidly into the iron age. Maybe if things go exceptionally and they cooperate flawlessly with no conflict and everyone is extremely industrious, best case scenario they can maybe inject some renaissance tech into the iron age here and there. They can't get further than this due to two major bottlenecks that just can't be resolved in one generation: infrastructure and genetics.

First, genetics. As many other answers state, they won't have access to domesticated crops. Even with perfectly executed breeding and hybriding practices, it will take many generations to have highly productive farms. It will also take some trial and error to identify what plants are even reliably edible, even with perfect knowledge. This is not a death sentence, the group can have tree branch spears and start persistence hunting on day one, however it does mean the vast majority of people will be involved in food production for the entire generation. I'm going to conservatively put it at 90% of the productive labor output of the entire group will be unable to contribute to advancing this society due to being occupied with keeping basic survival needs met for the entire 80+ years. But remember, if 10%, or even 1%, of the people are free to advance things they can get a lot done.

The second bottleneck is infrastructure. So much technology depends on standing on the shoulders of those who came before you. With perfect knowledge, you can maybe skip a step here and there (say, skipping bronze age and jumping right to iron), but ultimately you really can't bootstrap later technology because it all has hard dependencies on logistics and infrastructure that won't exist. Even if everyone knows everything about metallurgy, it doesn't help if there are no mines, transportation, furnaces, fuel supply, etc. There simply isn't enough time or labor to get around this, so we're limited to the tech that can be built in one lifetime from nothing. Which is basically what you see in the Primitive Technology videos above.

A third potential bottleneck here is disease. I'm not going to dig in to this one much because of the many variables here (are the people's immune systems completely naive to the new region, etc), but let's just assume a lot of people die and a lot of people live. Ultimately the outcome to this question is mostly the same whether we have a million survivors or 10,000.

Due to all this, my expectation is that a few metal tools and maybe even renaissance era gadgets will emerge, but do to lack of infrastructure, these will be the exception, not the rule. The majority of people will remain dedicated to stone tools and subsistence farming/hunting for a minimum of several generations.

Answer 8

One other consideration which can tack onto any other answer is megafauna. Your settlers will likely have access to huge populations of mammoths, bison, ground sloths, aurochs, elephants, and many other large animals. In the best case, if you were able to apply knowledge of traditional people who actually fought these animals in prehistory, this will solve all your food problems for the first few years and probably longer. In the worst case, if your settlers can't find a way to protect themselves, large predators will eat all of them instead.

Answer 9

You'd get to the Iron Age in a year or less.

I'm not certain how far you'd be able to get in a lifetime, but in a single year, you'd be able to go from absolutely nothing, to the Stone Age, to the Bronze Age, to the Iron Age. I know this because there's someone who's actually done this: a Youtuber named "How To Make Everything" started a series of videos on their channel where they started from nothing, build tools from wood, used those tools to build stone tools, and continued this iterative process of using his existing tools to build better tools over the course of the past year.

They've managed to create agriculture, several different types of food, a wide variety of metal and stone tools, the wheel, pottery, writing, and more. The answers who state that the people in this scenario are doomed are far too pessimistic; at a bare minimum, they'll be able to achieve rough parity with Medieval Europe in approximately a year.

How far they'd be able to progress over the course of a lifetime, I'm uncertain of (it's quite possible they'll get to steam and electricity), but they'll definitely be able to reach the Iron Age in short order.

Answer 10

Medieval technology, minus metals

Many others have pointed out the challenge of food. My solution is start with a smaller population (10,000) in a region with considerable native food (Amazon River basin). During an initial period, they use up most of the nearby native food, incrementally traveling farther out to gather more. This gives them enough time to establish more permanent sources of food (fishing, farming).

If you want to advance society, you need agriculture, which in turn means that at least some of your population is permanently settled. During the initial period, the others will be bringing back food to the settlements, which limits the radius of the area available for hunting/gathering to at most a few days' travel. This puts an upper limit to your initial population size; instead of 1 million, I believe 10,000 would be more practical.

Metals such as copper, tin, and iron vary in their location. I am going to assume the worst case that the population does not have the opportunity to find them. There still is a considerable amount of technology that be acquired without metals.

First month:

• Start with 10,000 people slightly upstream from the mouth of the Amazon River.
• All inhabitants travel no more than one hour by foot to gather food, returning to the settlement.
• Some people are going to get sick or die by poisonous food. Determine those plants which are non-poisonous and appear nutritious, and begin planting their seeds to establish agriculture.
• Hunting would be limited to any opportunities that arise.
• Create stone firepits, light the first fires.
• Construct temporary shelters.
• Begin collecting or making stone hand axes, spears, atlatls, and nets.
• Population likely to shrink to about 8000 due to dysentery, food poisoning, injury, and zoonotic diseases. Hunger is not yet the major killer.

By end of first year:

• Most (80-95%) inhabitants continue to work to get food. Those who remain in the settlement build tools, improve the settlement, are injured or sick, or are caring for others.
• Food gathering begins to expand outward from the settlement -- following the river or the coastline -- as nearby food is exhausted. Continue to try new foods and plant seeds of the most promising ones.
• Use spears and atlatls for hunting, and spears and nets for fishing in the river.
• Clear the settlement's land to gather wood and prepare farmland. Improve or build better shelters.
• Continue tool-making. Begin making handled axes and boats.
• Population likely to shrink to about 5000-7000. Starvation is most likely during this period.

By end of second year:

• Most of the population continues to gather food, but the yield of food by hunting and fishing steadily improves. Boats enable gathering and hunting parties to travel further upriver during the morning, returning to the settlement in the afternoon.
• The first crops of annual plants produce a tiny amount of food. Continue planting the most promising seeds gathered or grown.
• Gather clay, build kilns, begin making pottery.
• Make seaworthy boats.
• Population reaches its lowest point (about 5000).

By end of 5th year:

• Gathering and hunting continues to spread further out from the settlement.
• Farming continues to improve, although it continues to be a small portion of the diet. Annual plants have gone through several generations of selection, and perennial plants have their first crops.
• Begin ocean fishing and the domestication of animals. The former becomes an increasingly significant and renewable source of food.
• Begin making bricks and using them to build homes.
• Ceramic tools and utensils. Encourage writing and art on clay tablets and pottery.
• Population starts to slowly grow and to specialize in their jobs.

By end of 10th year:

• Farming improves enough to feed domesticated animals, and to supplement the human diet. Hunting and gathering of food declines. Fishing is a reliable source of food.
• Improved hand tools. Use of the wheel for carts and waterwheels. Quarrying and stonecarving. First grain mills. Digging of water wells.
• Part-time city council and constables. First written laws.
• Population is growing.

By end of 20th year:

• Although crude and not as nutritious and tasty as our modern versions -- which will take centuries -- crops are an adequate supplement to fishing and domesticated animals. Hunting and gathering are reduced to seasonal activities. This basic food paradigm will continue henceforth.
• Improved ocean ships. Fish oil for lamps and soapmaking. Breadmaking and ethanol.
• Leatherworking, bellows. Glassmaking for bottles, beads, and coins.
• Baby boom. First schools and library. Settlement begins to grow in area.

By end of 30th year:

• Less than half of the population is involved in food production.
• Looms and clothmaking. Wooden/ceramic screws and pulleys. Sailboats.
• Paper, inks, and ceramic typeface for printing press.
• Elected officials. Full-time constabulary.
• Concrete. Public buildings, canals, and sewers.
• Support of scholarly study and science. Recording of knowledge. First college, astronomical observatory, and hospital.
• Settlers travel up the river to establish the first new settlement.
• Continued population growth.

By end of 50th year:

• Regular trade between several cities. Roads, bridges, lighthouses.
• Printed books. Growth of schools and libraries.
• Dams, pumps, hot water, toilets, bathtubs. Glass windows. Apartment buildings.

By end of the 85th year:

• Technology has settled to as far as it can get without metals. If they are lucky to find metals, then their progress would follow Ash's answer more.
• Population has grown back to 10,000.

Answer 11

To add to AuronTLG's answer:

Farming depends a lot on humus, which in most places needs to be worked on also. Pre-historic tribes spent millennia cultivating their lands in a way that was beneficial to the micro fauna in humus, which lead to fertile lands. During the industrial age farm machinery basically destroyed all that hard work and nowadays large farms rely on artificial fertilizers to ensure crops can grow.

If your million people simply spawn on a virgin Earth that has never had humans, they will not have a layer of humus that is appropriate for whatever crops they bring. They will have to hunt and gather, which won't be enough for everyone. So most of them will starve, and the remainder will be stuck on a constant struggle for survival. Between fending off predators while hunting big game themselves, starting agriculture from scratch, and drinking only primitive moonshine beer because that's more sanitary than whatever water they collect, they won't have time to discuss the rocket equation and the square cube law.

Answer 12

Pre-Industrial era because one million don't need to go further.

Let's start with the assumption that they know everything. Just didn't had the opportunity to try it. The one with the best motor skills on day one learn the fastest and share the knowledge (like how to cut from yourself, never toward yourself).

Second is that, as I see, almost everyone is aware of the changes humanity did to food to have more of it. But they forget that if we reset to "day 0" we reset everything. The iron is just laying around. And they know how (and where) to look for more. There is no twelve thousand years of exploiting surface sources. And even now there are (of course in remote places) people who find (because they look for it) iron nuggets.

They also have knowledge about dangers. Dangers that come with humans not only from beasts and nature. Wooden houses burn whole cities? Place the building in distance that make it harder to do so. Sanitation is important. Place the little settlements in distance that don't also sikcness to spread easily but, at the same time, make communication easy. Medication - they have knowledge on what natural remedies are avaiable and for what they can be used. No experience? There had to be the first person who fixed open fracture.

From all "failed" experiment that lead to our current state-of-the-art technology they can choose ones that suit their needs and capabilities best in their current position.

Imagine it like a knowledge tree in the game. You need something so you see what you need to unlock to get that. And what you can ignore because you don't need it. Do you need to waste materials and time to make needle making machine? Do you really need to build Hoover dam to get enough power?

My great-grandparents were using tallow lamps in the early 1950's. Just because their village wasn't electrified. And they were doing fine (maybe not great but fine). You can, using knowledge, arrange living situation of 1 million people to maximise their comfort, health and progress.

Answer 13

Could advance to the Industrial Age within a generation.
Here are a few key factors which would make advancement much easier.

Easy access to the following resources in close proximity. 0) food & cloth. I’ll put this off for later.

1. anthracite coal. This allows you to fire kilns to a sufficiently high temperature to make steel. https://en.m.wikipedia.org/wiki/Anthracite

2. nearby iron deposit.

3. leadership. Once you start making steel products, life for everyone gets easier. Leadership needs to focus on getting kilns built and running ASAP so they can make high quality axes, saws, knives, shovels, picks. You’ve got a million people so organize 100k people smithing right away. This is your only hope for getting beyond subsistence living.

4. lime for concrete. Also requires kilns/coal.

5. copper & tin deposits for making bronze. If you don’t have anthracite coal, it’s probably faster to settle for bronze in the short term.

FOOD PRODUCTION Lots of people have ideas for food production. The first 5 or 10 years will be rough. Someone mentioned these kickstarters:

1. megafauna. massive herds of buffalo
2. Nile delta year round farming
3. flooded rice paddies. Lots of manual labor, but requires fewer tools in the short term. Produces crops year-round. Use ducks to keep the bugs under control?
4. fig trees produce lots of fruit for many months out of the year. They propagate fast and grow extremely fast.

It probably would take nearly 10 years to foster farmland/seeds/crops that yield enough grain to feed people. In the meantime you better hope that food from other sources doesn’t run out.

OTHER NECESSITIES Mass producing things like rope, cloth, etc. is a huge problem. Cotton & flax are even more labor intensive than food crops. Nearly as important as smithing.

Answer 14

I would suggest early middle ages with better medecine and sanitation but worse crops and only the unruliest of domesticated animals. Meaning iron is availible for the most important tools but expensive. And a much higher fraction of the population works as farmers.

Answer 15

No one has mentioned the fact that early civilization depended heavily if not entirely on slavery. Assuming people managed to achieve subsistence after arriving in this new world, it's hard to imagine how or why anyone would then start to put in the vast amount of work required to rebuild civilization without some rather nasty Mad Max style despots then coming into the picture and forcing them to keep on task (assuming said despots don't also give up on the mission and settle for the wealth and power they've achieved thus far). I'm not sure that civilization can be born in this manner. Civilization seems like a side effect of the rich and powerful enslaving and/or domesticating the rest of the population for so long they learned to accept it and make the most of it.

Answer 16

They could make little house in the first day and hopefully use fire that first day as well. After that they can make bows and arrows to help them with hunting. They would need to hunt all the time until the first winter to have enough food to survive it. After that they could have the time to start gardening. That will give them so much more free time to do things such as making better homes. They might start to make villages after the first few years. After that they might want to explore even more so they will spread out and maybe make kingdom's after decades.

By now the timeline is almost up so they can't get much more done. But they could start to focus on more things like science now that they made a basic society.

They might learn some things about outer space during the last few years and they might even be able to run in more human kingdom's as well. By chance, some of them will get iron from comets. Those kingdoms might be able to do more advanced things such as make musical instruments like drums if they get enough iron.

They might even start mining and get their hands on other gems before the generation is up.

It would be hard to say all of the different things that they could do if they get their hands on iron, but it would be roughly around the late mid evil times maybe.

Answer 17

Although these are premises but "All are Healthy" and "All are single minded and peaceful" are two conflicting conditions. Healthy Society will have people with Different Minds and being Violent is one of them.

Anyways:

They can reach Moon in one life time(85 years). Perfectly possible. They don't have to necessarily pass through "ALL" the civilization ages, they can directly jump to today. Well technologically most time would be taken to build machines that in turn build other machines. Once machine-building machines are built, technology can progress at exponential speed.