# How to calculate the probability of survival of a young civilization

In a fictional world a young civilization is struggling for survival.

Round about a century ago, it broke up with the core-society that was just beginning to establish itself on an inhospitable planet. The hiving off was accompanied by a war, involving heavy losses. Meanwhile the war is over, but there are still occasional raids going on. In fact there are more than these two groups loitering around, but let´s keep things simple.

Our young civilization is surrounded by a voluptuous vegetation and dangerous animals living in it. As a result of the fight for survival and due to the penchant of some of the early leaders, people began to calculate their own possibility of survival called “ProProg” (Prognosis of Progression). Absolutely everything is tagged with a number that ranks its contribution to the ubiquitous ProProg. For e.g. a method to control the birth-rate gets a high positive ranking. The birth-rate itself , depending on the actual situation, is ranked too. Production of goods is ranked. Technical innovations are ranked. The quality of ore recently has become worse, so it has been down ranked. But at the same time, a gas pipeline-worker made a proposal how to only defecate every three days without getting digestive problems and thus saving precious time. So there’s an up valuation of the ProProg here. The way people (and even children) contribute to the ProProg in their spare time is ranked. And the ranking can be negative too, so people get aware of favourable and unfavourable behaviour every minute of the day. How many and how severe raids have there been ultimately? Being it wild beasts or the other “tribe”. How probable is the eruption of a near volcano? All these tiny to big rankings are pooled in one big number, the actual ProProg. A ProProg of 100 would mean: survival granted for the next 500 years, no threats at all. Birth-rate is going up, production growth stable and political stability granted. Right now the ProProg is around 38, meaning that there is a good chance to survive the next 190 years, but a lot of problems still are unsolved.

Besides the psychological effect, in a positive as well as in a negative way, does this make any sense? Which sectors in such a civilization are essential to be ranked? Is it somehow feasible to gather this huge amount of data and make one sustainable number out of it? Can there be one formula to rule them all? Would it really help a young civilization to blossom? A lot of questions, but I think they all stay in the frame of the main topic. Some more specific indications (Meant to help frame the answer and not to be taken too literally. Also referring to the above mentioned examples):

• The society has a stage of development comparable to middle Europe +/- 1880.
• It´s political and social framework is mostly technocratic.
• No electricity. Main energy source is natural gas in diverse refined conditions. Gas sources are everywhere. Here our society is far beyond the technical status of earth´s 1880.
• The whole administration and calculation is based on paperwork.
• All devices used to help calculating should be similar to the ones used on earth until 1880, unless the availability of different types of gas allows other.
• Steel is produced.
• Lots of construction wood in the surroundings.
• Just one other humanoid group.
• A very solid and gigantic “town hall”, allowing shelter to most citizens and main production facilities.
• I am afraid that you will not be able to crunch the necessary numbers with 1880 technology. But other than that it looks like an intriguing idea. – Olga Nov 20 '17 at 11:25
• If you started out with only a few hundred individuals, and certainly without careful screening of individuals and pairings (not likely in a pre-electricity, 1880 European society, even with abundant energy available from natural gas) it seems likely that you'll see the effects of a genetic bottleneck at some point. You might want to compare present-day cheetahs. – user Nov 20 '17 at 11:46

TLDR; "It’s difficult to make predictions, especially about the future". (Attributed to many famous people; the Quote Investigator attributes it to Karl Kristian Steincke)

## Garbage In, Garbage Out

So we have this cilization which aims to "establish itself on an inhospitable planet" and has a "stage of development comparable to middle Europe [around] 1880". I won't be snarky and point out that the stage of development of, for example, (little) Romania (oh my country!) around 1880 and the stage of development of, for example, the United Kingdom around 1880 were profoundly different. (To illustrate, Romania experienced massive peasant uprisings in 1888 and 1907; in 1880 Romania had about 1400 km of railroads while Britain had about 29000 km.) So let's assume the best of the best, and consider that this society has a stage of development similar to Britain around 1880.

• The first strange thing is how could a society similar to Britain in 1880 get to aim to establish itself on another world. This does not compute. To be in a position to aim to establish themselves on another world they must have started from a very advanced society, several centuries more advanced than ours. How did they forget how to make electric generators, electric motors, light bulbs, electronic valves (they can be made at home), how did they forget radio and television? This is crucial; societies cannot forget selectively. Either they went through a long phase of complete illiteracy, in which case, sorry, but a hundred thousand people society will not reach a level of development similar to 1880 Britain (maybe, just maybe, they could reach a level of development similar to 5th century BCE Athens), or this is simply inconceivable.

• The second strange thing is how did this society similar to 1880 Britain get this obsession with planning? Are they by any chance Marxist-Leninists enthralled by five year plans and the dream of building a perfect society? (Note that not even the Soviet Union tried to aim for global optimization of progress; they simply established that some things were "good", such as producing many tons of steel per head, introducing many hectares into cultivation, opening many miles of railroads and canals, etc. and went for it.)

But anyway, let's take the premise as given. We have a society similar to Britain in 1880 which is curiously fascinated by a numbers, specifically by computing a prognosis of progression, which, by the way, is specified only as a "prossibility of survival". "Right now the ProProg is around 38, meaning that there is a good chance to survive the next 190 years, but a lot of problems still are unsolved". All right, but what are the threats? That is to say, why wouldn't their society survive five hundred years? Will the bears eat them? Is the climate changing? Are the gas reserves running out? The question does not specify.

So we have "everybody" providing a daily ranking of their contribution to the probabilty of survival of the society. Now, here come the first problems:

• Both Lenin and Kerensky will estimate their contributions to 100. One of them is wrong, but which one? How can the Central Institute of Totally Democratic and Objective and Definitely Not Totalitarian Statistics decide whether Lenin is right or Kerensky is right without having to fight a civil war to find out?

• How do they solve the problem of the shortage of clairvoyants? The invention of the internal combustion engine was considered a great achievment in the late 1800s, and it took a hundred years for society to realize that burning a lot of hydrocarbons poses a clear and present threat to the survival of the human civilization. Birth rates? Should they be high or low? Would the invention of television be rated 100 or 0? How to decide?

In short:

• The input numbers are completely untrustworthy. Individual rankings are purely subjective. "Societal" estimations are, to use a term from dialectical materialism, historically determined, that is, they are constrained by the level of development of the society. Burning gas was seen a a good thing in 1880, not so much in 2017.

Ah, but we'll have an army of trusted estimators (a.k.a. the KGB) providing estimations of each individual's contribution, and we'll have Central Planning Committee providing estimations for inventions and innovations. True, it didn't work on Earth, but our society is different! We'll develop a perfect method of divining the future impact of any invention or innovation! We'll grow a generation of perfect snitches, intelligent, benevolent and with the capacity to see the future!

Basically, garbage in.

• The thing with history is that it's long and unpredictable. Children's activity in school and out of school is ranked... by fortune tellers, presumably; because how can one provide a trustworthy evaluation of a child's future contributions to society? Maybe the child will develop into a Faraday (born in a poor family), or a Tesla (born in a faraway and backwards country)? As children neither of them had any readily apparent prospects to do anything important in life, and yet they proved essential to the development of human civilization.

How can the Totally Democratic and Transparent Planning Committee of Clairvoyants decide how to weigh the individual numbers? They are submerged in a deluge of numbers: the boy Joseph Vissarionovich did great in school, the girl Marie Sklodowska no so well, a scientist named William Thomson discovered a method to compute the maximum signalling rate on a long cable, an economist named Karl Marx published an analysis of the capitalist mode of production... How can the committee judge how important is any of this events relative to the others? How can they tell which is positive and which is negative?

In the question, it is said that "the quality of ore recently has become worse". This is bad, undoubtely. But what if this deterioration of the quality of ore spurs the mining company to explore new deposits, thus finding a much better source of ore?

Basically, garbage out.

This looks a lot like Asimov's psychohistory but using only the current situation not projecting against changes to the situation. Your numbers are far too small for his purposes but the principle is the same at heart. It is hence a concept that a SciFi audience will accept.

There can be one formula to rule them all

# Problems exist

Many of these problems are solved by the much larger population numbers Asimov insisted on.

• Their technology isn't good enough to gather the data required for the number to be correct.
• 100 people surrounded by tigers are more bothered about whether they're going to survive into next week, never mind next century.
• The more factors you introduce, the more complex the formula, the less meaning it has to the ordinary person, and the closer it gets to 0.
• The mere presence of a volcano above their only town should reset the number to a permanent 0.
• On any day someone could go out into the jungle and catch the fever that will wipe them all out, the mere existence of something like ebola would give a permanent 0.
• You have to know what it is that's going to kill you to be able to do something about it.
• There can be one formula to rule them all but taken alone it has no meaning.

The granularity of data is there in the calculations, but the grand formula takes away any use it has in projecting the future. It becomes a toy for morale and nothing more, you need to hope it keeps rising.

To do anything with this number, to improve their survival, it has to be looked at as a series of values, one for each threat against the factors that mitigate that particular threat.

That sounds a lot like an insurance risk calculation though, which begs the question, when did insurance first come about? Lloyd's Coffee House was the place to go to get your insurance in the early days. Now known as Lloyds of London it was founded in 1688, so it's perfectly reasonable to be making risk calculations against a basis of 1880 technology.

• "You have to know what it is that's going to kill you to be able to do something about it." Perhaps extreme case of this: A tiger is going to kill you. So you pull out the big gun and shoot every tiger you see, and so does everyone else. Except that you happen to be behind a tiger from someone else's point of view, so the bullet goes through the tiger, then through you. Maybe that tiger was even going to kill you, and you were out of ammunition, or plain didn't see it. You are now just as dead as you would have been, but the cause of death has changed. – user Nov 20 '17 at 12:31
• @MichaelKjörling, that just means you have to add "idiot with a gun" to your list of potential factors – Separatrix Nov 20 '17 at 12:36
• The principle of psychohistory is that the individual is largely irrelevant though, a few people will die on the tiger hunt, but if the tigers are gone then the civilisation as a whole is no longer at risk of tiger. The small number calculation here is whether the civilisation is more at risk from loss of those people now than the risk of tiger later. – Separatrix Nov 20 '17 at 12:40
• "It becomes a toy for morale and nothing more, you need to hope it keeps rising." This right here is exactly how I feel about this concept. Just like the doomsday clock idea, it's all about taming public hysteria rather than solving the problems at hand. – V. Sim Feb 24 '20 at 18:51

Our young civilization is surrounded by a voluptuous vegetation and dangerous animals living in it. As a result of the fight for survival and due to the penchant of some of the early leaders, people began to calculate their own possibility of survival called “ProProg” (Prognosis of Progression).

There are two kinds of society :

1. Survival problem ? Focus energies on solving the problem. This type survives.

2. Survival problem ? Focus energies on calculating the odds of surviving. This type becomes extinct.

The number you are describing would not, ever, be done by detailed calculation, but by some sort of empirical rule of thumb guess-work formula. It's the sort of number politicians like and technocrats actually have utter disdain for, because the number is useless in and off itself. The number provides no information on the nature of the problem and no idea at all how to solve it. It distracts from the problem itself and it uses resources to make it which could be better spent elsewhere.

The society has a stage of development comparable to middle Europe +/- 1880.

We're almost 150 years in advance of that and we can't make such an estimate.

And we'd never agree on one estimate anyway.

Your society could never produce a useful estimate. All it could produce is a useless one done for dogmatic purpose ( "we must have a number, even if it's pointless" ).

It´s political and social framework is mostly technocratic. No electricity.

We had electricity in the 1880's, if they had comparable technology to ours in 1880 and were technocrats then they would inevitably focus research on producing an electrical power production and distribution system over the less efficient gas. Electrical power is essential for forward development of technology - you can't match it with gas, and they would know that.

Main energy source is natural gas in diverse refined conditions. Gas sources are everywhere. Here our society is far beyond the technical status of earth´s 1880.

This technology is limited. Electric lighting is far superior to gas - you can generate much brighter lighting even with early versions of light bulbs. High speed devices for machining need electric motor technologies - gas won't ever do it. Switching systems (like phones and primitive computing devices) require electricity.

As technocrats they would know this. Gas is a dead end technology for their society.

The whole administration and calculation is based on paperwork.

So they're not a technocracy, but a bureaucracy. :-)

Once you start down the road of organizing everything around a dogmatic principle with no value (calculating the odds of survival) your entire organizational system will become warped to that purpose and everything else will become secondary. The bureaucrats and administrators will become the controllers and the technocrats will loose out.

That's inevitable.

The only way to have a technocracy is to make developing the technology for society's benefit a primary purpose - you need "social technocrats". And you need to ditch the daft calculation to make this work.

All devices used to help calculating should be similar to the ones used on earth until 1880, unless the availability of different types of gas allows other.

Different gas won't fix the fundamental fact that electrical devices allow faster and smaller and easier to maintain calculating machines than gas ever could. This is simple physics and would be plain as day to your technocrats.

Steel is produced.

In what quantities ? You have a tiny population to try and sustain even basic levels of steel production. I do not believe this is economically viable.

Lots of construction wood in the surroundings.

Oh joy. :-)

Note also implies a lot of woodland that's soaks up resources to clear for agricultural production and housing needs.

Just one other humanoid group.

That's so vague as to be useless. Are they enemies ? Are they friends ? Are they neutral ? Are they more advanced, less advanced, about the same ? Are they integrated into your society or completely apart ? Are you able to communicate with them on any level ? If you can't answer detailed questions like this then leave this other race out of your story altogether.

In a single century ???

Even if a quarter of the population are of child-bearing age in any five year period and they produce four children per couple in that period that survive to adulthood, they will barely be able to make the 100,000 mark in a 100 years.

But just sex alone won't keep a population alive !

They need food and shelter. And in your society they also need education and light and heat and protection and health care.

And that takes time to build and resources to make. Humans take time to grown and are not productive for the early part of their lives and cannot be as physically productive in their later years.

Factoring in all these things means your society will expend most of it's resources in simply expanding it's numbers and being able to keep them.

Rather than being able to focus on technology, they'll have to focus on agriculture and basic building and basic infrastructure - try designing and maintaining a sewage and water system for just 100,000 people !

So this is not realistic in any way. They'd have a hard time just maintaining the technological level they started with, let alone improving it.

A very solid and gigantic “town hall”, allowing shelter to most citizens and main production facilities

A town hall large enough to house and shelter, say, 70,000 people in even the most basic conditions would be vast - an engineering feet beyond the ability of their technology and one that would be a massive undertaking for us now. Without the development of 20th century levels of water production, sewage management, cleaning systems and agriculture you would have nothing more that a miserable disease ridden slum.

The availability of wood makes the building of normal small dwellings more likely, simpler and more cost effective. This won't reduce or remove the requirement for a sophisticated system as described, but it's not as difficult to build and maintain as your giant hall.

The giant hall would be a serious problem in that it is difficult to expand it as the population grows. A modular town hall would be little more than a lot of connected sheds - useless for housing a population and it's social needs as well as production facilities.

So the giant hall is a non-starter.

Beware tautology, predictions of any kind tend to be self-reinforcing, any data that comes out of ProProg will be problematic. Actually it's worse than that, ProProg is going to be prone to turning recursive since it has to take the manifold effects of ProProg into account in it's calculations (if the ProProg output data are made public, which they have to be if you want to act on them), that will alter said calculations which will also alter those calculations and so on. You will have extreme difficulty, as in it will be next to impossible, in getting anything usable out of a system that's sensitive enough to provide accurate predictions and then anything you get will start a fresh recursion loop.

The concept isn't exactly a non-starter but you have to be very careful to put some solid limits around what it monitors and how the data are presented to the public, if at all. A dip is of course worse than a lift, humans tend to panic during downturns, (see every market crash in history), but even a sustained high number can be tricky if people stop paying attention.

The number in itself has no meaning and even less value.

The process to derive it, if rigorous enough, could be very helpful indeed.

What you really need is a way to move resources from one sector to another in order to maximize the number.

This is done very badly "on paper" and this is the real reason of (initial) Apple success: the first program readily enabling to do this kind of calculations (the first spreadsheet) "VisiCalc", but I'm digressing.

For sure you need to, in some way, approximate this computation in order to manage the colony development. It is one of the "modern" discoveries that many interactions in complex systems are highly counter-intuitive and thus the development of a series of tools (from the above cited VisiCalc down) to help managers, at all levels, to take their decisions.

If useful to your plot you can devise a specific "plan office" where some skilled humans will emulate this "optimization" process "by hand".

Bear in mind the whole process will start as a very rough model and will be refined over the time, along with techniques for multi-variate maximization.

You need something similar to what has been done in early '70s by "Club of Rome" to give a rough estimate to The_Limits to Growth (it has been heavily ridiculed at the time, but many of graphs proved somewhat true, unfortunately).

Reliability of computations in a small and culturally compact colony would be much more reliable than what possible in a 7billion+ inhabitants world with many conflicting entities.

• VisiCalc didn't invent anything revolutionarily new, though; it simply took an existing practice and moved it to a computer, greatly simplifying the work involved. (That's not to say that this didn't change things in practice; just that it was "only" an optimization of an existing process.) Running the numbers was standard practice, though done by hand on a blackboard rather than automatically on a computer. – user Nov 20 '17 at 12:33

Have a look at Maslow's hierarchy of needs.

Based on your original premise, this is a splinter group from a colony that I would assume was seeded by an advanced civilization. So at least initially, the possibility that the know-how to prevent or minimize the risks of in-breeding would have been available, and I am sure that the means to grow the population in that regards safely would have been passed down to later generations, even if the why wasn't.

Similarly, the original colonists would have been aware of the above-mentioned hierarchy, or something similar, and so have based their rating scale on that. Initially physiological and safety needs would have been the primary focus, but they would have recognized that for their civilization to not only survive, but endure, the other needs would also need to be addressed at some point - and not in the too distant future either - "all work and no play" would have serious repercussions early on in the game.

Another important aspect to rating an improvement would be how many people will benefit and/ or suffer from an event/ implementation.

So one method would for the colony's founders to have broadly ranked ideas according to Maslow's hierarchy. If someone came up with an idea which might benefit a large number of the colony's population, the value of the benefit might either be put before a committee for ranking, or even put to a popular vote (as this might supply a benefit both the Love/ belonging and Esteem steps).

If the benefit was deemed to be good for a smaller number of people, it would rather be decided on by the people potentially affected.

But ultimately, the score could be worked out along the lines of rank on the hierarchy x ( percentage of population benefited - percentage of population harmed ).

Very good answers so far. From me just some afterthoughts:

Sounds like a steampunk and Difference engine setting. No problem there in 1880.

Electricity just seems to be forgotten or impossible on this planet, perhaps too few or the wrong metalls, metall eating bugs / coroding plant sap ... and very good hard wood for your gas and difference engines?

I would expect your number 38 to be determined empirical, but then you would need experience with a lot of such colonies in the past (some big amounts of historical data from other planets or the last 10.000 years in books?) or very good models (calculated with your difference engine or by hand on paper).

To get more experience I would split (at least virtual) the colony in several self-governed parts. After some time the fitness of all the parts would be compared and correlated to their decisions. The fitness would be your number, e.g. calculated with number of children, combined weight of people, calories in stock, time with digestive problems and such. The more successfull parts would get resources (like people just voting with their feet) from the less successfull parts, splitting and diversifying again after a certain size is reached.

A hundred thousand (and fast growing) people just doesn't sound very "inhospitable" ;-)

The Lindy Effect may make fools of your prognosticators.

The theory called the Lindy Effect basically says that the life expectancy of a particular thing (such as a civilization) can be expected to be about its current age. Your civilization ultimately will come to an end (unless the apocalypse comes first), so the question is not whether, but when. If it has survived for a century so far, the best bet is that it has another century left in it. But if it survives a second century, it can then be expected to survive two more.

The logic here is that the future is fundamentally unpredictable, but some societies are more robust to changing conditions than others, and this can only be observed over time. The longer they survive, for whatever reason, the longer you can expect that they will continue surviving. This applies even if the reasons they survive are entirely different from the reasons they think they will survive.