The collapse and collapse of the Roman Empire is a matter that is being debated time and again, because we believe that our civilisation can follow the destiny of the Roman: to weaken and fall. In Rome's, we can see the paradigm of collapsing societies.

Historians, and more people, have debated this to come up with dozens of explanations: invasions of barbarians, epidemics, lead poisoning, moral decadence and many others. Which one is right or all are right? I will base myself on the interpretation of Joseph Tainter [EE.UU. 1949, anthropologist and historian, author of the famous Collapse of Complex Societies], empire and civilization as ‘complex’ systems, and I will use the dynamics of systems to describe the collapse.

The disaster seen from within

Let's start with the beginning ... Did the Romans themselves understand what was happening to them? It's important that a society, its rulers, understands that a collapse comes to it, can it do something to avoid it?

We have a lot of Roman historian texts, but nobody seemed to understand what was going to happen. Historians of the time were mostly chroniclers, counting acontecimientos.Por so it seems interesting to look at the writings of people who were not historians, who experienced the collapse of the Roman Empire.

I'm going to start with Emperor Marcus Aurelius. He lived in the years 120-180 of post-Christ. He was the last emperor to have a powerful empire. He spent most of his life fighting to keep the empire intact, against the barbarians. Marcus Aurelius appears in the first pictures of the film “Gladiator”. He died in the fight against invasions.

Marcus Aurelius managed to keep the barbarians on the runway, but within a few decades of his death, the Empire collapsed when historians called it a “3rd century crisis.” The Empire had survived for a couple of centuries, but it was not the same, it was enough to survive as it could, fighting between barbarians, pests, famines, caciques and disasters that came one after the other. Later, the Empire disappeared as a political being, in the 5th century, at least in the West.

The “Emperor philosopher” Marcus Aurelius left his ideas in the book Reflexiones [in original Greek Ta eis heauton], with excerpts such as:

“If you lived three thousand years, or even ten thousand years, remember that man loses only the life he now lives, he lives only the life he now spends.”

The man who has written the reflection is seeing his world collapse and striving to maintain a personal balance, a moral attitude. Aurelius was sure to have understood that something was wrong with the Empire. The Romans had always attacked and now defended themselves. But in Gogoetak you will never read about the need for the barbarians to do more than fight, about social change, on the disastrous march of the economy. Apparently, I did not think the Empire could fall today, if not tomorrow.

I would now like to mention to you another document of the Roman Empire, De Redu suo [His return in Basque], written by a Rutilius Namatianus. At the beginning of the 15th century, Patricio Namatianus lived. He held a position in the administration of the Empire in Rome, decades before the "official" destruction of the Western Roman Empire (year 476). With his book they have also made a film in Italy, De Redu – Il Ritorno.

Namatianus realized that it was not possible to continue living in Rome. Everything collapsed around him, so he took a boat and went to his native Gaul, which today we call France. It offers us a terrible explanation of the trip:

“I’ve chosen to come back by sea, by land roads or flooded or filled with stones. Leaving Tuscany through the Via Aurelia, as after Godo attacked with fire or sword there is no house to control the forests or bridge to cross the rivers, I have chosen to go by the sea rather than venture there.”

It seems incredible. The Romans were always proud of their roads. No Roman empire can exist without roads. Namatianus tells us about the ports that have taken the mud that it sees along the Italian coast to the north, the fueled cities, the landscapes loaded with ruins.
He sees the collapse around him, but he can't understand it. It has to be a headache, a terrible time that Rome had already lived, but that has always risen and overcame its enemies. It has always been that way, Rome will be strong and rich again.

He could have provided more documents, but the Romans have not understood what was going on with his empire. It seems that weaknesses can be fixed by expanding the army or by building larger walls. This shows us how the collapse is lived from within. Most people don't see what's going on, like fish: you can't see the water.

What destroyed the Roman Empire

Although we've lost a lot of documents and data, we have a lot of information about this empire, a lot more so than other ancient empires that have been collapsed and disappeared. But we do not agree on the reasons for the collapse.

Edward Gibbon quotes in the famous Decline and Fall of the Roman Empire that Christianity had a negative influence, that the noble virtues of the ancient Romans were corrupted by those fanatics who came from the East and prevented the barbarians from facing up. You will probably agree if I say that this explanation seems rather limited, like that of subsequent authors, like Splenger and Toynbee.

I believe that the original interpretation of Roman decadence was given by Joseph Tainter in the book The Collapse of Complex Societies, published in 1990. It provides very rich information about the collapses, but also about the Romans.

Society, says Tainter, is complex beings and that is why its collapse must be linked to complexity. What he said asked in the documentary Blind Spot [2008, Punto Ciego] sums up Tainter's thinking:

“In the old societies I’ve analyzed, as in the Roman Empire, the main problem was that they only had to face high costs to sustain the status quo. Invest very high amounts to solve problems that no longer had a net positive return, but did not allow them to maintain what they already had. This reduces the performance of a complex society.”

The fact is that the Roman Empire entered a catastrophic loss of complexity in the third century. It was the real collapse. But let us mention the many reasons people give about the collapse. Again and again there are the only causes that explain the collapse, and there are people who fall in love with them: “I have the solution, this is and nothing else.”

It has been said that the Roman Empire was destroyed because the Romans drank wine in lead forests, causing them to die poisoned. There is some truth in the skeletons of the ancient Romans that indicate that it has been poisoned with lead. There was probably a problem, perhaps a serious one, but it can't pose it in isolation. Imagine a future story saying that the U.S. Empire was destroyed because the Americans ate burgers.

The same is true of other unique causes, such as climate change. Evidence shows that the fall of the Roman Empire coincided with droughts. They certainly were a problem for the Romans. But can you say that the history of the future brought Hurricane Katrina to the U.S. empire?

A complex being must fall in a complex way. Societies always face crises and challenges of many classes. For them, the answer is usually the organization of structures, such as bureaucratic or military structures. Whenever a crisis is resolved, society is endowed with a new layer of complexity. Then, as complexity increases, the performance of each extra complexity that Tainter calls ‘marginal benefit of complexity’ begins to decrease.

It happens because complexity has a cost: maintaining complex systems costs energy. As you increase complexity, performance becomes negative, the cost of complexity outweighs performance. At any given moment, the burden of complex structures is so great that the whole of society collapses -- that's the collapse.

Societies adapt to change. One of the characteristics of complex systems is their adaptation to the changing external conditions. This feature that defines a system as complex (and not just complicated) is called “homeostasis”. When you work with complex systems, you don’t think of the terms “cause and influence” but of the terms “forcing and feedback.” “Forcing” is something that comes from outside the system. “Feed-back”, response of the system to external pressure, which supposes a certain homeostasis.

Homeostasis is a basic concept in the dynamics of systems. Something influences something else, but this also reacts. That's the feed-back. It can be positive (reinforcing) or negative (damping, damping) and we mention feed-back circuits, which generally stabilize systems within certain limits.

Homeostasis must be well understood. It is not the same as equilibrium, as defined in thermodynamics. For example, the human being is a complex system. When you live, you're in homeostasis. Instead, if you're in balance, it means you're dead. Homeostasis is the dynamic balance of forces.

On the other hand, homeostasis cannot be opposed to the principles of the fish you are swimming at sea sica.Imag. Physics says it can float, but it needs to spend some energies to maintain the homeostasis conditions to get out of the surface of the water. Think he's now hooked his leg with some weight. So physics says you're going to sink. But you can spend more energy, swim harder and keep your head above the surface of the water -- back in homeostasis. But if nothing changes, the energy will be extinguished in an instant, it will become fatigued and it will not be able to retain homeostasis. At that moment physics will take over and sink, it will choke. They can withstand homeostasis for a while, while they have the means to dissipate it.

Dynamic models of collapse

As we speak of complexity, we can compare the Tainter model with other models. We can turn directly to the study of the Growth Limits of 1972, the mother of all theories. [The Limits to Growth was made on behalf of the Club of Rome and financed by the Volkswagen Foundation. Meadows, Dennis L Meadows, Jorgen Randers and William Behrensek. They simulated Earth's interactions and consequences with human systems using the World3 model.

The authors of Muga del Desarrollo wanted to describe the current world, but the model used by them is very general and can be applied to the Roman Empire. To understand how it works, I'll show you the following graphic image of the model:

Here you have the population, agriculture, natural resources, pollution and capital. The model consists of five components that intuitively understand the meaning of each one. The important thing is the feed-back relationship between these components. Perhaps there is the most important feed-back link between capital and resources. This is described in the study Limits to Growth:

“The stock of industrial capital grows at a level that requires enormous resource input. It exhausts many of the resources available in the growth process. As resource prices increase and mines run out, more and more capital needs to be allocated to the acquisition of resources, reducing their use in future growth. In the end, investment cannot keep pace with depreciation and the industry base collapses, dragging with it services and agriculture systems, which have been subjected to industrial inputs.”

You can play with images of Myrtveit and compare this to what Tainter has said about societies. Tainter said that if a crisis occurs, society will try to overcome it. From the scheme you can see what happens as time advances and people try to avoid collapse.

Let us think that pollution has become a serious problem. Big humareds spilled by fireplaces kill people, and then society is going to put capital to reduce fumes. For example, it will put filters into chimneys. But to make filters, you need energy and natural resources, which will create more pressure on natural resources. This is going to put pressure on capital, so the fight against pollution can increase the speed of collapse, but not fighting can also lead to collapse, although for different reasons: pollution kills people and that causes capital to reproduce with greater difficulty, etc. That's how the model works.

Another example. Suppose the population grows to the point where there is not enough food for everyone. In response, society will use its own natural resources for fertiliser production in order to increase crop productivity. This, however, will lead to an even greater increase in the population, putting pressure on the population and increasing pollution, leading to new pressure on capital and resources, etc. Within some limits, society can always adapt in that way, that is the homeostasis we have mentioned before. But only within a few limits.

In this game you can play in different ways. Magne Myrtveit’s five-component image is a good tool to feel how society reacts to external interventions and how it changes as natural resources run out. If these resources are non-renewable, as is the case with our minerals, the amount of capital that can be generated and retained will be reduced. This is one of the possible causes of the collapse, probably the most frequent. But to understand how it's going to happen, you need to use the model on your computer and see what it gives you. Below is the result of the 2004 edition of Border to Growth (in the graph on the page).

The parameters of the scenario are very close to the current situation. You can see how collapse occurs, when you see industrial and agricultural production sink. When the industrial and agricultural system is blocked, its complexity falls (and, of course, also the population). Thus, to put it somewhat, the report model Limits to Growth is compatible with the model of Tainter.

People are very good at optimizing exploitation. The problem is that it exaggerates and takes the system more than the system itself can replace. That's the essence of the curve. First you go up because you are so good at exploiting the resource; then you go down because it has exploded too much. In the middle there is a peak: there is the peak resource, the summit of the resource. In the case of oil, people often talk about “peak oil.” Given civilisation as a whole, we should say “peak civilisation”, the summit of civilisation.

And as we have said, the culmination of civilization is the summit of complexity (“peak complexity”), as Tainter has described.

Collapse is not inevitable. Once society has gone too far, it collapses, but the collapse gives it time to change the overexploited resource, and growth can start again in a while. But this happens when the resource is renewable. If it is not like oil or uranium, once spent, it is no longer. In this case, the collapse has no turning back.

Similarly, as far as the human being is concerned, even if a society can recover from the collapse, it will tend to be longer than a person's life. So, as far as we are concerned, the collapse has no turning back if it takes us, and that, of course, we do not like anything.

Decline dynamics of the Roman Empire

The Roman Empire was based mainly on two resources: the army and agriculture. I have put the image of the legionary to the section of “capital resources”, because the legions were the capital of Rome, the military capitals. This was built on a natural resource: gold. The legions did not take gold out of the underground, but picked it up from people who had previously unearthed it, or who had stolen the miner.

Tainter explained that military adventures were of fundamental importance in the expansion of the Empire. The Empire was defeating a neighboring kingdom, stealing gold from it, and boosting a portion of its inhabitants for slavery. With gold, he paid more legions and thus conquered new lands. There was a positive feed-back: the more legions were available, the more gold was stolen; the more gold it was, the more legions formed. Etc.

One of the Roman inventions is to turn gold into gold for legions and legions. We still say “soldier” (soldier, renewables, soldier…), which in Latin means “salaried”.

But as the conquests prospered, the Romans soon found themselves without land that would allow them to conquer. The problem was the Energy Return on Energy Invested Rate; in this case it would be GROGI. After the conquests of the first century, things got complicated. The energy gain gained from the conquest of new territories decreased. In the Northeast, the Germans were too poor and also belligerent. Their conquest, besides being difficult, left no benefits. In the East, deliveries were very rich, but very strong in military terms. Then, further west, the Atlantic Sea, the North too cold, the South too dry. Negative feed-back, do you see?

When the legions had not brought him any more gold, the gold had vanished from the Empire for several reasons. On the one hand, to buy luxury things from abroad, because the Empire didn't manufacture them, like silk. On the other hand, the leaders of the barbarians had to be paid not to invade or combat the Empire. Gold was everything for us for the Roman Empire -- "black gold," oil. In times of prosperity, legions brought more gold than they had spent, but over time the balance became negative.

And then there was agriculture. This can also give positive and negative feedback, as you can see in the scheme. With good agriculture the population increases and as a result you have more peasants. In the case of the Roman Empire, as the population increased, they could have more legions back and forth that brought the slaves to work in the camps. But agriculture also gets negative feedback, and it's erosion, erosion.

We can place the wear in the place where there is pollution (“pollution”) in the scheme. It adversely affects agriculture. It reduces the population little and everything becomes worse. The more it forces itself to feed a larger agricultural population (including legions), the more violent the fertile soil is. This is not a renewable resource, it takes centuries to rebuild fertile soil once lost. Wear destroys agriculture, the population shrinks, legions also have less, and in the end … the barbarians invade you.

Overexploitation of resources

From the data we have, we can understand why the Roman Empire was gravely concerned. His army, composed of legions, had to be paid and the military did not make any profits. It was the beginning of a gold hemorrhage that could not be interrupted. In addition, the Empire lost more blood because of the need to build a comprehensive and expensive system of forts to monitor and manage borders.

The fortifications account explains what happens to a complex system when it wants to maintain homeostasis. Because legions were too expensive, barriers were being built to preserve borders, which would require too many legions. Slaves were going to be built, and the slave was cheaper than the legionary. But slaves were not good at fighting. You will know the story of Spartacus, the leader of the slave rebellion: the Romans would not want it to be repeated. Slaves have been used for the fences, because it takes less legionaries than to defend the border in a broad field. Saving money is a homeostasis effort.

However, the Romans needed men, legionaries, to put on all the fences and these were extremely expensive. The Empire climbed into a cage and never managed to escape. Negative feed-back kills.

Military spending has not been the only cause of the fall. Seeing that erosion ruined agricultural land and that mine productivity was in decline, we should not be surprised to see the Empire at its core. It couldn't be otherwise. The collapse of the Roman Empire has been a complex phenomenon of negative factors that have strengthened each other. The negative feed-back, one after the other, plunged the Empire. This shows how close we are to the Romans.

There are undoubtedly differences: our society is more linked to mining and less based on armies. We don't use slaves, but machines. We have a lot of upheavals that the Romans did not have. But, after all, the interactions between the different components of our economy are not so different.

What plunged the Romans will also sink us: the overexploitation of resources. If the Romans had figured out how to use their resources, agriculture, for example, without destroying, to prevent, for example, erosion, their society would have endured more time. But they never found the point of balance, and they came to grips with what they had.

Avoid collapse

Suppose someone had things very clear at the time of Marcus Aurelius. Imagine a British Druid, Merlin's ancestor, fast enough to realize what was happening, that the Empire's concern was felt by the negative feed-back, the army's costs and the bureaucracy, the overexploitation of fertile soil and the depletion of the simple yodots conquered by Rome.

Just like Merlin had done with King Arthur, the druid believed he had to tell the emperor when he went to Rome. I have often thought about what I would say to him being in his place.

For example, if gold has been reduced, why not tell him to arrange an expedition to America? This is what Columbus did a thousand years and a peak later and about what Spain built the empire. But the Romans lacked the right technology to traverse the ocean, and to develop it, they had exhausted their resources. They had to stay in Europe, arrange them within the boundaries of the occupied area. Therefore, like the Druid that has left England, you cannot give the emperor only one tip: you have to return within the limits that the economy of the Empire will be able to sustain.

So, because of your reputation as a wise man, the emperor receives you in your palace, and you tell him what you have found:

"Emperor, the empire is doomed. If you don’t do something now, it will sink in a few decades.”

The emperor is perplexed, but he is patient. Philosopher, after all. He will not order to decapitate him as the other emperors would, and he asked him: “But why do you say that, druid wise?”

You say: “Look, you spend too much money on legions and fortifications. The gold accumulated in the secular conquests is disappearing and you cannot afford to be legionary enough to defend your borders. In addition, there is too much pressure on agriculture, soil erodes and loses. There will soon be no longer enough food for the Romans. In conclusion, you are drowning the people with too big and expensive bureaucracy.”

The emperor has once again had the idea of beheading him, but he will not; you are very lucky to meet an emperor philosopher. And he asks her. “There may be some truth in what he says, but what should he do, wise druid?”

"First planting trees, the land needs rest. Over time the trees will make the earth fruitful.”

“But if we plant trees, Emperors, there will be not enough food for people.”

“No one will be hungry if the patricians give up their luxuries.”

- “Well, Mr. Druida, I understand your vision but it will not be easy…”

“And you have to trim your many legions and leave the walls.”

“But… Druida… if we do, the barbarians will invade us…”.

- “Better Orian than I do. Now you have enough troops to defend your cities. It will be impossible later. Make a lasting defense.”

"Permanent?"

"Yes, it means the defense you can afford. You have to turn legions into a militia of the city and… ”

“And…?”

-You have to spend less on the imperial bureaucracy. The taxes of the Empire are too high! You have to work with people, don't step on people! Plant trees, reduce the army, work together!”

On this occasion Marcus Aurelius has seriously examined whether it would not be appropriate to decapitate him. But since he is a good man, he has sent you back to England, escorted by a hard military guard, with strict instructions that you do not return to Rome.

This anecdote that has never happened is very similar to what happened to the authors of “The Limitis to Growth,” these modern druids. They were trying to tell those who once were rulers of the world something similar. The authors of “The Limits tho Growth” did not cut their necks, but, to put it another way, they decapitated them “academically”. Download it. They made them ridiculous, they made fun of them. It's not easy to be druid.

Here is another similarity between our contemporaries and those of Rome. We live the fate of the “fish in the water”, we do not understand that we are surrounded by water. And we don't want to hear the water closing.

We are happily going down the same road as the Roman Empire did. Our leaders are not able to understand complex systems and continue to implement solutions that worsen the problem. Just as the wise druid tried to explain to Marcus Aurelius, the building of walls to leave out the barbarians was not only useless, but also a great loss of resources. We can imagine the politicians of that time saying: “Let’s keep the barbarians out! Build more fences to defend the Empire!” Today we have the same situation. Tell a politician that we have oil problems and he will answer “Zulatu sakonago!” or “drill, baby, drill!”. Negative feed-back kills.

Controlled transition

But there's more. Druida told Aurelius “plant trees, reduce the army, collaborate.” Have you thought about what I was proposing? A world composed of cities defended by urban militias, without central or very weak command, an economy based on agriculture. You will realize: It's the Middle Ages! Thinking about it, the Middle Ages have been the solution to the problems of the Roman Empire. The Empire was going to do it and couldn't avoid it. What Druida proposed was to go to it but in a controlled way. Facilitate the transition, not fight it! If you know where you're going, you can travel in style and comfort. If you don’t know… the journey will be hard.

If the Roman Empire had made a “controlled transition” in the time of Marcus Aurelius, it would have done precisely: to abandon the walls, to mutter the number of legions and become an urban militia, to reduce the expenses of the bureaucracy and the Empire, to decentralize authority, to reduce the pressure on agriculture: to plant forests. The transition would not be traumatic and would result in less loss of complexity: books, knowledge, works of art and much more could be saved to leave them in the hands of future generations.

But this is just a chimera, a prefect. Nor would it have been easy for a Roman emperor to dissolve legions. The emperor was a military commander and to be Imperator he had to please the legions. An emperor who would have wanted to annihilate the legions would not be very popular and would probably have lived for a short time. So even if I had understood the dynamics of the systems, I wouldn't have been able to do much. Indeed, throughout his life, he was endeavouring to strengthen the army with as many legions as possible.

Emperors and the Roman world in general struggled to maintain the status quo before, as things had always been. III. After the crisis of the 20th century, Emperor Diocletianus revived the Empire making it something similar to what the Soviet Union of Breznev reminds us. An oppressive dictatorship that contained suffocating bureaucracy, high taxes for the citizens and a slow military structure. All of this was a heavy burden on the Empire, which led it to sink into the end of a century.

Today’s druids may be better than those of the Roman era, as they have digital computers. But our leaders are no better adapted to the complex systems of understanding than those of the Roman era. But even if we had better leaders, they should face the same problems: there are no structures where society is going to be carried comfortably. The only structures we have are able to maintain society as it is, no matter how difficult and uncomfortable it's going to be to stay there. That is what Tainter says: our way of dealing with problems is to build more and more complex structures that end up generating negative benefits. That is why societies are sinking.

All our efforts are to maintain that status quo before us. That's why we're desperately looking for something that represents oil and keeps all things as they are today. It should be something liquid, cumbersome and, if possible, odor. Dig more, drill more, cook the sand tar, even though people have to go hungry doing biofuels. Anything, if everything remains the same.

But we're still in the direction that the laws of physics lead us: a world less oil, or nothing oil, can't be the same as the world we're used to. It is not just a return to the Middle Ages. If we manage to expand new sources of energy, renewables or nuclear, to replace oil and other fossil fuels in time, we can estimate that the transition would not result in a great loss of complexity, perhaps no loss. But most likely, as the flow of energy and natural resources decreases, the economic system will be affected by a collapse like the one shown in the simulations of The Limits to Growth. We cannot help but go where the laws of physics lead us.

Last word: decisive moment in Teutoburg

Two thousand years ago, three Roman legions were destroyed by the Romans in the jungles of Teutoburg, joined by tribes called “Germania.” In recent years the forests of this region are peaceful places, as you can see in the photos.

We can hardly imagine what would be the three days of that battle. The legions were surprised by the Germans, who, desperately, tried to squint in the woods, where there were heavy rains and strong winds, and the legions were unable to complete the ranks and fight as they were trained. One by one, the majority were killed; General Varus committed suicide. The Germans let the corpses rot in the forest as if it were the sacred memories of the battle. Even more sadly, the legions lost their sacred standards. So great was the disaster that the legend said that Emperor Augustus was accustomed every night to those places “Varus, give me back my legions!”

We remember for a moment those men, the Germans and the Romans, who so passionately fought and murieron.Podemos to see great similarities between our world and that of Rome, we can also feel what those men felt. Why did they fight, why did they die? Many of them paid for war. Others by order of the commander or chief. But I am convinced that a good number of them would assume that they were fighting for an abstract (or not) concept that was the Roman Empire. Some would feel that they were fighting to defend civilisation against the barbarians, others to defend their land against the invading enemy.

Two thousand years later, we realized how useless that struggle was in the rainy jungle. A few years later, Roman General Germanicus, the nephew of Emperor Tiberius, returned with at least eight legions to Teutoburg. They defeated the Germans, recovered the banners of the torn legions and buried the dead Roman soldiers. The Germanic leader who defeated Varus, Arminius, lost his reputation and was soon murdered by his own inhabitants. But that didn't change anything.

The Roman Empire had exhausted its resources and could not extend them anywhere else. Germanicus could not conquer Germania in the same way that Varus had not been able to return his legions from the kingdom of the dead.

Civilization and empires, after all, are nothing but waves in an ocean that is time. They come and go, leaving little traces, except the sculptured stones that proclaim their eternal greatness. But from a human point of view, empires last a long time and, for some of us, it is worth fighting for them or against them. But those who fought in Teutoburg didn't change the line of history, as we can't. The only thing we can say is – as then, now – that we are going to a world of the future to which we can only perceive one aspect vago.Si we could clearly see where we are going, perhaps we would not want to go, but anyway we are going. Finally, perhaps it was Marcus Aurelius who saw the future more clearly:

“The nature that governs everything will soon change all the things you see, and the same substance will do different things, and its substance will do other things again, so that the world will always be new.” (Marcus Aurelius Verus - Meditation to 167 after Christ)