A classic with some flaws.

Reads more like a whose who of the anthropology department. Probably best held as an exquisite example of why academia is a excellent place for good thoughts to die under the weight of pretension. You could say the entire theory in a single page and then put the rest in the appendix.

This was one of those books that will forever change the way I look at the world. Tainter analizes societal collapse the way you would expect a physicist to. He cuts through our human tendency to explain complex events with narrative confabulations and instead proposes a model of collapse that is grounded in first principles thinking.

Ok, done!

Tainter's work is an opus. How could it be otherwise with a title like that? Yet, it lives up to the title: aiming and broadly succeeding to argue the causes for collapse. It's a little ponderous to read, because it is documented and reasoned like a thesis. This is a historical analysis, with applicability to our age that's noted only lightly along the way: it's not a political position paper, though it could be.

Tainter says diminishing returns eventually trap civilization in a no-win situation. The idea of diminishing returns (well explored) meaning that more fertilizer, internet, railroads and regulations produce more food per man-hour invested, but only to a point. Eventually the return on investment tapers to nothing, and then further effort would actually COST energy, blood and treasure. ...and critically, you can't go back.

I don't think he successfully argues why we can't step back from that precipice, why for instance the diminishing returns aren't their own regulator, moreso because the broad curve of lost benefit implies a smooth hilltop, not a cliff (My precipice description makes Tainter's point, but it seems inaccurate to describe the actual dynamics.) It seems pretty simple negative feedback: the farmer eventually looks at a JET powered tractor, (plows 20% faster, but uses 3x the gas) & thinks, "no thanks." There IS a valid issue of "measurement delays" though. Maybe when you're a city planner contemplating a bridge too far it's not obvious that it's total cost/value is a losing proposition. Surely there will someday be one road too many, if not already!

Another possibility (I'm trying to cinch down the last loose knot on his thesis, you see) is that the complexity is a house of cards. A famous "cappuccino" speech (by Greenspan) trumpets the hyper-complicated chain of products that enables something as wonderful and only SEEMINGLY simple as a cappuccino: where'd the ore for the selenium cobalt in the magnets in the electric motor that ground the beans come from? If our system is interdependent (and surely it is for is not the efficiency derived substantially from specialization that interdependence allows?) then perhaps because of fragility it cannot regress to a simpler time. There is no retrenchment possible; removing a keystone will bring it all down, and every stone is a keystone.

A final idea I'll offer is that we become addicted. Not in a bad way either. We are addicted in that we want to support our population: it's not o.k. with us if people die. But that's what will happen because, as we expand our capability (e.g. the green revolution that fed Asia), we respond by literally eating up that excess capacity. Some of it goes into luxury, but lots goes into people too, and we are thereby committed to the additional technology. I heard a great study about a lane mover that would increase one way traffic on the I-70 corridor during ski season. 50% less crowds? No, the crowds will respond, said the analysis, and it'll just be 50% more people skiing, with the same traffic jam as ever. I believe it! We invent an improvement and then gobble up it's benefit instead of banking it away against lean times. So the change becomes not really an improvement, but instead a permanent commitment to additional infrastructure, additional complexity. In Skinner's Walden II they lived a life of ease founded upon 30% more efficient work habits. Why then don't I live a life of ease with (the US average) 10kW at my disposal? That's the equivalent of a dozen horses, working for me 24/7. The answer is that we use it up. Also I suppose I DO live a life of ease and luxury in comparison to a 19th century Russian peasant with only one actual horse in his stable. Anyway, Tainter does talk about this obliquely at one point.

Re-reading my review a year later, both Tainter's analysis and mine leave me uncomfortable, unsatisfied. Trying to be succinct, I don't think it's about diminishing returns, but about slack and momentum. Consumption of all the slack technology provides leads to an irrevocable commitment to complexity and interdependency. "Commitment" is the mouths to feed, and it's the inertia you need to make instability possible. Commitment means you can't retrench to simpler technology in a bad year because the greater efficiency has become the new minimum baseline. Now you're in danger of actual collapse.

One more last thought (how many "last thoughts" is one allowed?) is that maybe the famous hidden "negative externalities" provide the extra lag in measurement that could trip us over the self limiting point of diminishing returns and into an unsustainable vicious cycle of collapse. The farmer buying the fast tractor doesn't see the oil cost in it's impact on fertilizer cost, or food prices in poor countries, or something similar, so he makes what is for him the right Local decision, but Globally, it is the wrong one.

Of course bringing oil into it pulls Jared Diamond to mind. Only soil, Diamond's favorite limited resource, could be more apt. Here's a link to some comparison between this book and Diamond's Collapse.

About a year later, a gloomy note  from Thomas Edsall of NYT opining that America's had her run, and will be next. Hope he's wrong.

And later still, the latest foodie trend here in Boulder is to disparage the humble wheat stalk, it's multifarious chromosome threatening our digestion. What if this graduates from trend to generally accepted fact? What if the ideal response is to regress to einkorn and yields drop by half? Just in case society does collapse, I'll document the fall here, so at least at the end I can say "I told ya so!" (I expect there's a great business in Cassandrasim, but the rewards are fleeting.)

It took a long time but I finally got around to finish Joseph Tainter's anthropological inquiry The Collapse of Complex Societies.
The book's central thesis is that societies collapse because of declining marginal returns on investment in complexity i.e. initially complexity affords a society abundant advantages but after a certain point further investment nets less and less returns until the ROI becomes negative.
At this point the society becomes fragile and it's only a matter of time before "stress surges" (famine, drought, plague, war, invasion, etc.) do them in.
I liked that Tainter systematically went over other theories and actually addressed their points before going into the body of the text, criticizing some for being incomplete while dismissing others.
While I don't agree entirely with Tainter its refreshing to see an author actually engage with other academics' arguments, the book is extensively cited for one's convenience. Its a very well-researched work.
Overall, I think Tainter puts too much stock on the integration model and is too quick to discard the conflict model of society (one is tempted to ask why exactly, if societies are composed of rational actors, don't the individuals in charge realize they're pursuing a losing strategy and change course) but as whole, The Collapse of Complex Societies' thesis is disturbingly compelling, the book is a must-read for history buffs interested in collapsology.

This is a fascinating subject that was handled academically. In fact, it was like reading a research paper, which is to say factual and precise, but dry, so it took me longer to read than I had expected. I've enjoyed watching many talks by Tainter, so I was looking forward to reading this. Overall, I was not disappointed, despite a few minor criticisms.

The thesis is that complex societies are problem solving organizations that require energy, but that increased complexity leads to diminishing marginal returns until lower complexity becomes the optimal problem solving social structure.

The book is not without flaws.

First, the examples used in understanding diminishing marginal returns could have been both broader and deeper.

Second, Tainter examines current theory in causes of collapse: resource depletion, new resources, catastrophes, insufficient response to circumstances, other complex societies, intruders, mismanagement, and mystical. In trying to develop his unifying theory, he was perhaps overly dismissive of the other theories, especially mystical as a story-telling perspective rather than scientific study.

Third, Tainter spends considerable time applying his thesis to three case studies: Roman, Maya, and Chaco societies. The treatment was thorough but redundant. I would like to see how the thesis can be applied to many other societies, including our own global civilization.

This brings up the fourth criticism. In the final chapter, Tainter is seems to hedge his bets about the current possibility of complex by refusing to dismiss infinite substitution as wishful thinking, especially regarding peak oil (and, actually, peak everything) and biodiversity. See Richard Heinberg for more on peak oil and Ronald Wright about the myth of progress and the progress trap.

In fact, he never even mentioned anthropogenic mass extinction. He hardly acknowledges, reluctantly, that if the global complex society were to collapse, it would do so together. To this point I agree, and believe we are already in the beginning of a centuries-long decline. See John Michael Greer for more on the current long decline.

I have yet to read Collapse by Jared Diamond, but am looking forward to seeing how his views support or differ from Tainter's.

In "The Collapse of Complex Societies," Joseph Tainter offers a compelling examination of the rise and fall of civilisations throughout history. As I delved into the pages of this book, I found myself drawn into a world of ancient empires and modern societies, all struggling with the same fundamental problem: how to maintain their complex systems in the face of mounting challenges.

Tainter's prose is elegant and precise, weaving a rich tapestry of historical examples and theoretical insights. His arguments are nuanced and thought-provoking, challenging readers to question their assumptions about the nature of civilisation and the forces that shape it.

As a writer, I was particularly struck by Tainter's ability to distil complex ideas into simple, accessible language. He has a gift for making the arcane seem clear, and the abstract seem concrete, and his writing is a pleasure to read.

I would highly recommend "The Collapse of Complex Societies" to anyone interested in history, anthropology, or sociology. Tainter's insights are profound, and his analysis is both rigorous and engaging. This book is a must-read for anyone seeking a deeper understanding of the forces that shape our world. Four stars, without a doubt.

Most of the critiques one could make about Tainter's Collapse of Complex Societies are attributable to its very nature as an academic book, and as such are not all that fair to make. The book feels long and repetitive as it attempts to draw a rather exhaustive list of illustrative examples which it revisits several times, first factually, then under the lens of various theories and ideas. Academically, this reinforces the argumentation and makes the case all the stronger, which is the reason behind this writing style. Same can be said of the listing of various theories from prior authors, or of the frequent use of summarisation chapter to chapter. Of course if one takes this as a book for the general public - which it isn't -, then the writing feels clunky and many sections sound redundant. The reader should be aware of this going in, but ought to remember the intended public for this was academic peers, students perhaps, but certainly not members of the general public simply interested in the topic at hand. I do wish there was a version of this book that was reshuffled and re-written for that purpose indeed, as I do think the form will deter many - and certainly made this far less enjoyable for me to read than it could have been -, which is quite a shame in light of the interesting content that hides behind it.

The introductory chapter does do a good job of making the subject feel interesting. Collapsed civilizations, ruins and lost empires have quite a mystique aura to them, and Tainter does a good job of leveraging that aura to engage the reader. He also points to the evident yet all important connection between the collapse of societies past and the possible collapse of current civilization; he even cites The Limits to Growth in this part which is interesting to see. The author's definition of collapse - a relatively abrupt decrease in a society's complexity - leads one to think about whether we should voluntarily collapse in as controlled a manner as possible to achieve a 'sustainable transition'. Indeed, in many instances, an eerie feeling of familiarity affects the reader as they go through the stories of various civilizations collapsing.

The stated objective of this book is to develop and make the case for a theory of collapse that can explain all societal collapses through history, both on the very large scale such as the endlessly discussed Roman Empire, and on the much smaller scale of lesser known civilizations.

The author first takes great length to rule out the most common existing theories of collapse. Most of these arguments I find rather valid and are much the same. Saying that an empire was overruled by 'barbarian invasions' does not explain collapse, because by nature a large empire should always win against smaller barbarian societies. For it to collapse, there must have been collapsing processes upstream that fragilized the empire to start with. Saying that 'severe droughts' terminated a centuries-old civilization encounters the same problem. Why would a civilization that survived many droughts and similar events suddenly be overwhelmed? Again there must be a deeper fragilization process upstream wherein lies the true cause of collapse. Tainter also briefly mentions some more old fashioned types of theories which are pretty much trivial to invalidate: talking points along the lines of 'cultural degenerescence', 'losing touch with the glorious past' etc.

There is one theory which he brushes off yet where my biggest critic of his entire reasoning lies: chance concatenation of events. He gives it a half assed paragraph where there is no true argument really, yet I don't see how this is a crazy theory. Why would an empire yield to barbarian invasions after withstanding them for centuries? Because it was dealing with droughts and a plague at the same time. That to me isn't at all a farfetched explanation, though I will concede it must be possible to find examples where that wasn't the case as far as we know.

After duly rejecting currently available theories for being inadequate to his stated purpose as a good academic, Tainter then proceeds to describe his own. The thesis boils down to a cost benefit analysis.

Societies become complex to solve problems. An agricultural society is more complex to manage than hunter-gatherer bands; large empires are more powerful than small tribes, but require an increasing amount of administration, logistics, specialization, and organization. The author makes an interesting point in saying that complexity is an unusual, recent development in human societies, and that for most of human history, social structures were very small, simple, centered around a tribal or even familial nexus. It is also quite clear, based on the given definition of complexity, that the society of today is enormously complex - perhaps the most complex it has ever been. Complexity enables improved food supplies, improved military power, increased specialization, increased tertiarization and education, etc.

As society progresses in complexity, the benefits of its increased complexity decline - there are declining marginal returns to the complexity investment. This appears relatively logical - the benefits of the most basic sanitation and hygiene measures do much more for overall human health than ultra specialist biologic cancer-targetting therapy, and the scientific benefits of Isaac Newton theorising about gravity have much broader ripple effects than ultra specialist topics of today. It is much more of a relative leap in food security to go from a family nexus of hunter gatherers to an organized agricultural tribe than it is to unite agricultural sub-cores under higher hierarchy. Although the modern farm has much higher overall yields, because it requires such a complex network of productive society around it - steel plants for the machines, engineers, chemical plant staff, repair people, hydroponics etc etc, not to mention research -, the yield per unit labour actually decreases (or so Tainter says). Rome gained relatively less fom its conquest of Britain under the Empire than it did from its conquest of Italy. The most readily collectable resources are those humans exploited first, and so the cost of further extraction increases. Some of the arguments are shaky, but overall the point appears acceptable as a premice.

Although challenges can be seen to all of the above, the core assumption in this work is that societies will reach a point where this escalates. Eventually an increase in complexity yields benefits lesser than its costs, and after a transitory phase where the society clings on to ever increasing complexity, there is collapse and abrupt decline in complexity and social structure. The trigger or tipping point can be anything, as stated above: climate events, conquest, invasion, spread of disease, famine, currency debasing, alienation of the over-taxed population, etc. Technological innovation can forestall declining marginal returns only so long, and a new energy subsidy is essential to avoiding this fragilizing phenomenon.

Tainter mentions that complex societies evolve to overcome regular, semi-predictable crises e.g. droughts, but count on their surplus of ressources gleaned from their complexity to surmount major unforeseen crises. He then says that with diminshing marginal returns, complex societies become increasingly vulnerable to such catastrophes. That is one way to think about it, but the flipside is to say that chance concatenation of events, which he never rejected in a meaningful or valid way, could overwhelm a same given surplus that would have been sufficient had the events been dispersed in time. So I still think there is a very weak point in the thesis presented here there.

A final important point is the clustering of complex societies. Most of the historical examples described in the book pertain to isolated complex societies surrounded by less complex ones - the Roman Empire being a prime example. When several complex societies exist at once in a cluster, or as Tainter terms it 'peer polities', any decrease in complexity almost immediately equates to invasion by neighbours. Therefore, investment in complexity must be maintained irrespective of costs and returns. He applies this to the Maya, and uses this as an explanation for the simultaneous collapse of many societies within a few decades. He also argues this creates class conflict. Peasant revolts cannot aim for decomposition of the state, because it would then just be replaced by another, similar state, with similar domination and no overall loss of complexity. Revolts must thus aim at reformation in this context, to improve their share of returns on complexity.

The book goes in depth intro three examples from very complex (Roman Empire) to smaller scale and less complex, to show how the theory can be applied and how it applies at any scale. Rome made enormous benefits from its earlier conquests - Gaul was ripe with manpower and loot -, especially on a transient level. As it grew, the costs of maintaining the existent empire could no longer be met by further conquest into ever more distant territory. Several of the later conquests (Britain, Trajan's ventures against Parthia) were relatively short-lived as a result. The cost of the standing army and the administration became overwhelming as the size of the Empire became very large - this is an example of increased cost to no benefit, i.e. to maintain the status quo of stability (another example being the constant need for research to stay competitive in an arms race). After centuries of attempted adaptation to this through currency devaluation and other things (skipping details here), the empire became vulnerable and eventually collapsed on its Western side. The Mayan example also focuses interestingly a bit more on the resilience of food systems, where a lack of variety in crops made the entire food supply vulnerable. When drops of production between regions are asynchronous, this promotes cooperation in the form of exchange and trade; when it drops everywhere synchronously, it promotes pillage and warfare. I don't particularly see how this can be framed as an issue of declining marginal returns of complexity, but it is a good point nonetheless. The third in-depth example is much smaller scale and I didn't really make much note of it to be honest.

These chapters going through in-depth examples in addition to the brief chapter rejecting existing theories and the final chapter are perhaps the most worthwhile here, as most of the rest of the book is spent on surface level examples, although as mentioned above I do find it interstingly eerie to read about some of them. Reading about the Mesopotamian collapse out of greed, overexploitation of ressources, short term yield being valued over sustainability, all leading to ecological and social collapse sounds awfully modern doesn't it. The Mycenian example, where collapse in one place affected surrounding societies, also made me think of the whole question of climate migration, including that related to political instability. The fall of the Roman Empire beautifully echoes the modern problems of globalization and the vulnerability that it creates. I will say though that most of these links are not explicitly made by the author - they are just an interesting thought to have while reading. Tainter does recognize that lots of this book sounds like the doom and gloom of The Limits to Growth though, and also points out some of the current vulnerabilities - e.g. the inability of most of the current population to produce primary resources and grow food, which makes highly industrialized societies very vulnerable to a potential collapse. The world of today is also essentially one giant cluster of complex societies, and so per this theory, would be likely to collapse all at once if it collapses at all. At any rate, a nation can no longer unilaterally collapse, as it will likely be absorbed or receive international help. This is also true of voluntary collapse: economic degrowth, he says, cannot work, because the risk posed by unilaterally reducing growth is too great; withdrawing from the spiral is too much of a risk for any one society. Although the book only briefly touches on energy and its role in complexity, it does mention it is about the only way to combat the decline of marginal returns with increasing complexity, and makes note (in 1975!) of the then recent events indicating fossil fuels had already reached their point of declining returns. New abundant energy sources will be necessary and should be heavily researched and cooperatively funded if we are to avoid collapse, he says.

Of important note, collapse is not the only way a society can end. Both the Ottoman and Byzantine empires slowly degraded and lost territory over time, but there was no collapse as the land was taken over by equally complex adversaries and therefore there was no overall loss of complexity. Collapse can only occur to a society more complex than its neighbours, or to a cluster of equally complex polities collapsing all at the same time. Collapse is not the same as a change of ruler or regime. Tainter acknowledges that, although his theory is meant to be all encompassing, that does not mean it is the only possible mechanism of collapse - he points to nuclear warfare being a possible cause of collapse that has nothing to do with declining marginal returns.

Phew. This was a very long, hard to write review, but that shows how interesting I found this book despite a few gaps in its reasoning imho. The format of it, and again I can't blame the author for this, is the only major hurdle, but is enough to make it difficult to recommend. This is a shame because, as explained above, the theory presented here is a really interesting prism to look at world events and history through. The final chapter is a breath of fresh air as it skips a lot of the academic exemplification and just focuses on the discussion of concepts and brief examples, and it is well worth reading. Much like an academic paper, most of the interest lies in the final discussion and conclusion after all.

4.5 for its ideas, but for the actual book 3/5

Interesting thesis on the collapse of complex societies. The author starts with a review of possible causes for collapse proposed in the literature and moves on with a theory, technical and mathematical, about the importance of economic weakness. In a few words, most events leading to collapse (invasion, natural catastrophe, resource depletion, ...) require a process of economic weakness to trigger such a collapse; otherwise the society withstands the event. It is a difficult read, with the historian or sociologist as target audience I presume.

Tainter's work here is a dissection of what it means for a society to 'collapse', and an attempt at a rigorous causal explanation for why that collapse happens. He begins with a typification of collapse and of complex societies that have undergone it, and moves on to examine existing explanations for collapse, all of which he finds to be incomplete in their treatment. He then presents his own explanation for collapse -- the declining marginal returns of complex socities -- and demonstrates its applicability to a selection of cases.

While for the most part convincing, Tainter's thesis has a few holes worthy of highlight. His rejections of existing theories as incomplete seem to often focus on theories not spelling out a full causal chain between cause and effect to his satisfaction, rather than proper rejection of a causal link, and in that light his identification of declining marginal returns as the key factor can be cast in doubt compared to, for example, resource depletion, which seems more central to the economic argument he builds -- declining marginal returns being a seemingly unavoidable factor, but societies which discover new energy sources seeming to survive despite it. His treatment of modern staving off of collapse touches on this. A second hole is his treatment of collapse as happening only in a power vacuum, and that collapse cannot happen where there are competing societies which would predate upon weakening ones. At best, it would seem that this is a surface definition of collapse which leaves aside the possibility that collapses can be masked by conquests. At worst, it seems to suggest that complex societies that collapse must be isolated, or else that all their neighbours being less complex counts as such. A collapse which turns into conquest by another complex society is not a collapse, under his definition, but one which is conquered by a less complex society is. This point seems to decohere from earlier logic about the role of invasions in stressing a society.

On a somewhat less challenging note, Tainter's selection of examples seems unusual. He draws upon far more North and Central American societies in his examples than any from elsewhere. This may reflect his own background in archaeology, and is not necessarily problematic in a world literature which focuses heavily on the histories of Eurasian societies, but I do partly wonder if the choices of societies are motivated by popular concerns. Tainter's main examples are Romans, the Maya and the Chacoans, a combination which seems to lean heavily towards relevance to the modern United States, Rome being the cultural predecessor and the other two societies being roughly geographical ones. Tainter shows an awareness of popular interest in collapses, and I wonder if he thought of representativeness or cultural connection when building this analysis.

Disagreements aside, Tainter does seem to build a convincing explanation for collapses, even if his focus within the model is probably slightly askew. The level of scholarship is high, and his examples are well-argued. Lacking the ability to build quantitative tests of these theories, he has proceeded with a duly empirical presentation of cases, which is likely as best he can do. I expect that there will be developments which follow on from Tainter and adjust his model in various important ways, but I also expect that his field will not judge him as significantly misguided.

While on a trip to Peru I decided to tackle Joseph Tainter’s The Collapse of Complex Societies. I learned of this book from Thomas Homer-Dixon’s excellent The Upside of Down. Since we were once again headed to see some ruins, I thought this an appropriate time to approach this book, although in the case of the Incas, we can easily identify Guns, Germs, and Steel (and perhaps horses) as the proximate causes of collapse. But other cases, like the Maya, the Western Roman Empire, and Easter Island, are among those situations that do not provide easy explanations. Tainter reviews virtually all of the prevailing theories. He identifies the prevailing theory in popular thinking and among some historians (Toynbee, for instance) as “mystical” explanations, a poor choice of words to my mind. Toynbee, following a long pedigree, thinks in terms of biological analogies, with birth, youth, maturity, decline, and death the pattern for “civilizations” as well as individuals. This, Tainter argues, provides a false and rather misleading or unhelpful analogy. The other theory, of “decadence”, seems more literary and moral than causative. So what is Tainter’s alternative? Declining marginal returns on complexity (complexity being a term of art in this instance). In short, he bases his theory upon a fundamental economic law (if you will suffer the dubious term here). His analysis and application of his theory to the Western Roman Empire argues that it was not barbarians, Christians, or plagues that brought down Rome, but a limitation on the value of complexity. He applies a similar analysis to the Mayans and the Chaco Canyon civilization in North America. If he’s right, and I think that he makes a very strong argument (but see Peter Turchin’s War and Peace and War for an excellent competing theory), it has to be taken quite seriously, and if he’s right, then we have to think very carefully about our current predicament. Can we innovate our way out of the inevitable decline of petroleum? Can we get out from under excessive demands for complexity?

On a second reading, even better! A very thorough, careful analysis of phenomena that we have to take most seriously. Outstanding achievement.

A society has collapsed when it “displays a rapid, significant loss of an established level of sociopolitical complexity,” according to Tainter. Such complexity exhibits both inequality (vertical hierarchy) and heterogeneity (many components in the society). There were many theories that tried to explain such a collapse (e.g., resource depletion, catastrophes, intruders, etc.). However, each such theory has its issues. For example, all societies face catastrophes and intruders. But why do they collapse at some point but not at others?

The overall theory proposed by Tainter is rather clear and powerful. It can be broken down into 4 steps:
1. human societies are problem-solving organizations;
2. sociopolitical systems require energy for their maintenance;
3. increased complexity carries with it increased costs per capita; and
4. investment in sociopolitical complexity as a problem-solving response often reaches a point of declining marginal returns.
At that point, society experiences increased adversity, and the system searches for alternatives. Reduction of complexity (collapse as defined earlier) is often a way out.

For example, during the early time of Rome’s expansion, the booty could easily fund future expansion. But as the empire got big, the cost of maintaining the road, the legions, and the administration brought a significant tax burden to the point that the peasants invited “barbarians” to help. The Germanic kingdoms that succeeded Rome were more successful at resisting invasions at a lower level of complexity and cost, restoring the marginal cost of investment to a higher level.

Another example is of the preclassic and classic Maya. Cultivation of marginal lands and their agricultural practices made conflict and raiding common. This, in turn, selected for aggregation into the more secure political centers. The gained security comes at a cost of more population and large monuments to project their strength, leading to even more pressure on resources. The collapse, when it came, brought with it a crash of the number of monuments built during the period.

Overall, very articulate, structured writing propounding a generally persuasive theory with clear examples and nuances.