Civilizational Collapse (Part 4)

This is part 4 of an intermittent yet always enjoyable series:

Part 1: the rise of the ancient Puebloan civilization in the American Southwest from 10,000 BC to 750 AD.

Part 2: the rise and collapse of the ancient Puebloan civilization from 750 AD to 1350 AD.

Part 3: a simplified model of civilizational collapse.

This time let’s look at the collapse of Greek science and resulting loss of knowledge!

The Antikythera mechanism, found undersea in the Mediterranean, dates to somewhere between 200 and 60 BC. It’s a full-fledged analogue computer! It had at least 30 gears and could predict eclipses, even modelling changes in the Moon’s speed as it orbits the Earth.

What Greek knowledge was lost during the Roman takeover? We’ll never really know.

They killed Archimedes and plundered Syracuse in 212 BC. Ptolemy the Fat—”Physcon” —put an end to science in Alexandria in 154 BC with brutal persecutions.


Contrary to myth, Library of Alexandria was not destroyed once and for all in a single huge fire. The sixth head librarian, Aristarchus of Samothrace, fled when Physcon took over. The library was indeed set on fire in the civil war of 48 BC. But it seems to have lasted until 260 AD, when it basically lost its funding.



When the Romans took over, they dumbed things down. In his marvelous book The Forgotten Revolution, quoted below, Lucio Russo explains the evil effects.


Another example: we have the first four books by Apollonius on conic sections—the more elementary ones—but the other three have been lost.

Archimedes figured out the volume and surface area of a sphere, and the area under a parabola, in a letter to Eratosthenes. He used modern ideas like ‘infinitesimals’! The letter was repeatedly copied and made its way into a 10th-century Byzantine parchment manuscript. But this parchment was written over by Christian monks in the 13th century, and only rediscovered in 1906.


There’s no way to tell how much has been permanently lost. So we’ll never know the full heights of Greek science and mathematics. If we hadn’t found one example of an analogue computer in a shipwreck in 1902, we wouldn’t have guessed they could make those!

And we shouldn’t count on our current knowledge lasting forever, either.

Here are some more things to read. Most of all I recommend this book:

• Lucio Rosso, The Forgotten Revolution: How Science Was Born In 300 BC And Why It Had To Be Reborn, Springer, Berlin, 2013. (First chapter.)

Check out the review by Sandro Graffi (who taught me analysis when I was an undergrad at Princeton):

• Sandro Graffi, La Rivoluzione Dimenticata (The Forgotten Revolution), AMS Notices (May 1998), 601–605.

Only in 1998 did scholars get serious about recovering information from the Archimedes palimpsest using ultraviolet, infrared and other imaging techniques! You can now access it online:

The Archimedes Palimpsest Project.

Here’s a good book on the rediscovery and deciphering of the Archimedes palimpsest, and its mathematical meaning:

• Reviel Netz and William Noel, The Archimedes Codex: Revealing the
Secrets of the World’s Greatest Palimpsest
, Hachette, UK, 2011.

Here’s a video:

• William Noel, Revealing the lost codex of Archimedes, TED, May 29, 2012.

Here are 9 videos on recreating the Antikythera mechanism:

Machining the Antikythera mechanism, Clickspring.

The Wikipedia articles are good too:

• Wikipedia, Antikythera mechanism.

• Wikipedia, Archimedes palimpsest.

• Wikipedia, Library of Alexandria.

20 Responses to Civilizational Collapse (Part 4)

  1. Wolfgang says:

    It is very interesting to study the rise and fall of civilizations including thoughts about the probable fate of our current one, which, since the rise of natural science, seems to be on an eternally rising track, too.

    In this context, two ideas came to my mind.

    First, which of this future decline might happen already now? What I mean is the extreme specialization of fields, the extreme amount of scientific paper production, most of which are unfortunately noise, and the lack of overview both phenomena generate. How many mathematical theorems, for instance, are lost already from the start, because they were of lesser importance published in more obscure journals? Can one quantify this? Perhaps by noting the amount of reinventing and rediscovering facts over and over again?

    Second, if decline is inevitable, what are the best strategies to conserve the most important knowledge for future generations? Obviously, massive and wide dissemination should help, if random selection will take place. But maybe it could be good to write everything as neatly and concise in one big tome and store it in a safe somewhere? Like one does with the earth’s seeds in some bunker in greenland. But the problem seems not, to only write it down, but to make it accessible again to a, possibly, less experienced future generation, which has not only lost the knowledge but also the methods of learning and understanding it.

    I think the possible risk of loss of knowledge is highest with information stored electronically. We can read 2000 year old manuscripts, but not floppy disks from 20 years ago. Books seem indispensable for safe storage.

    I think Feynman once was asked, what would be the one scientific fact that entails the most information in order to be able to reconstruct most of science from scratch, and his conclusion was, “matter is made from atoms”.

    • Bob says:

      First, which of this future decline might happen already now?

      Historically, all booms are followed by a bust, and then a Great Depression. Then it starts up all over again; just with fewer people. Sort of like that child’s game, “musical chairs”.

      A lot of energy is wasted managing complexity because of lack of organization which is in part due to the lack of ‘sort space’ which results in information aliasing. Complexity makes it very costly to distinguish things. Information gets smeared out and blurry. For example, the pencil eraser that I keep losing gets buried on my desk among the clutter and then it reappears (gets rediscovered) in strange places. Sometimes it moves around in my subliminal and peripheral vision as if it were a tunnelling particle with ESP obeying some kind of quantum weirdity. Complexity generates a sort of phase change in the management requirements.

      Second, if decline is inevitable, what are the best strategies to conserve the most important knowledge for future generations?

      I’d preserve copies of Moby Dick, Hamlet, The Old Man and the Sea, Rod Serling’s Patterns,…
      Otherwise fossils and genes seem to be good ways to store information long term. In H.G.Wells’ The Time Machine, the question is posed to the audience: Which three books would they use to reboot a crashed civilization? I doubt you can tell a crashed civilization anything that would prevent them from making the same mistakes again. As the old saying goes, “Insanity is doing the same thing over and over again and expecting different results.”. You might try teaching them about “hotswapping” upgrades instead of using the cold boot corporate downsize-reorg model. As for rebooting science, that probably isn’t necessary: the most durable of facts are not perishables. They are indelible and they are not trying to hide.

      • Wolfgang says:

        True, fossils and genes are very good in storing information. In the human context paper still comes close, maybe just rivaled by clay discs. It is also true, that science does not need a backup copy, since the laws are still all out there to rediscover. It could be a hard time, though, to do that in practice from scratch. And is it really guaranteed that some Zweistein guy of the future comes up with the same idea of relativity? Well maybe, at some level of investigation, it is inevitable to do so. One possibly would also rediscover the Planck law by necessity. But then, mankind lived most of their history without doing science at all. Would there be a second Newton to start it? Would it be ignited from another field, say thermodynamics instead? How could that shape the minds of the future scientists and predispose them for other discoveries? Or is there something special about the laws of Nature, that would make mechanics always the best starting point and the most dominant way of thinking, like it happened in the past?

        • Bob says:

          Archimedes managed to be a genius far beyond his own place and time. His bouyancy principle will likely be a “gift that keeps on giving”. Exceptional people like Archimedes seem to be able to manage information without becoming confounded. Their wetware wiring stays manageable and tangle-free (defragged) even when flooded with mis-information. They seem to have limitless memory and be able to digest and condense information, using it for fuel.

          For others, opening a time capsule containing cheat-sheets would be a recipe for disaster, a real “Pandora’s Box”. As the old saying goes, “If you give an idiot a gun and he shoots someone with it, you don’t blame the idiot.”

          Or is there something special about the laws of Nature, that would make mechanics always the best starting point…

          Some laws are just speed bumps; they’re meaningful and useful in their context, but you can still get over them. Other laws will kill you if you break them. The most useful laws seem to be the ones that keep you alive long enough to appreciate them. So , if by “mechanics” if you mean “mortality”, then the supernatural (human) laws might be just as important as the natural ones. I almost gave up on the Mind-Body Problem after reading about Nicolas Malebranche’s gravitational theory of “swerving” atoms as a basis for free-will. Laws can be perverted. It’s unnerving how the 2nd Amendment can be used to build up a domestic army of insurgents who want to eliminate the Constitution. It’s un-nerving that pro-lifers want to force some women into a reproductive act against their will, but for some strange reason nobody is calling that ‘rape’. Ignorance is bliss. Optimistically I would concentrate more on opening horizons, opportunities, and options rather than building arks, time capsules, and infinity clocks

        • ecoquant says:

          @Bob,

          Some very old religious traditions believe that proper ethics, sociology (caring for the “widow and the orphan”), and environmental sensibility is wired into the fabric of the Cosmos. By that they mean if a society transgresses these boundaries, there are real costs associated with doing so. They don’t necessary mean that individuals who are responsible for anything pay. But, to some extent, if someone arises and is permitted to do bad things, it is partly the responsibility of the society about them for failing to intervene to stop them.

          Accordingly, I think, they would judge that the bad actor is a symptom of a corruption in the society, and that corruption eventually earns its own punishment.

  2. Ammar Husain says:

    Wonder how much that Ptolemaic family dysfunction contributed to Physcon. Did he have any of those genetic disorders?

  3. Here is a simple example which struck me while watching a documentary of the Roman invasion of Britain. The Romans built homes (mainly for the commanders ) with underfloor heating which can still be inspected in a a few places. The locals never seemed to take to this technology and I suspected it was because it was the technology of the conquerer – bugger them we will live in the damp and cold and show them! So a bit of useful technology just disappeared apparently. It never formed part of castles, or stately homes let alone a tenement in London as far as I can tell.

    I think electronic storage is incredibly fragile and there are big businesses built around migrating movies, images (eg Getty Images) from one form of storage to another as the technology changes.

    • John Baez says:

      Peter wrote:

      bugger them we will live in the damp and cold and show them!

      My father, who worked as an editor for Forest Service in the U.S. government, had a Scottish officemate who seemed to have internalized this attitude. He would leave the windows open even in the winter.

      Yes, electronic storage is fragile and ever-changing. From the Atlas of Digital Damages:

      “When the US space agency NASA sent two Viking Landers to Mars in 1975 to find out whether life might exist on the red planet, it was assumed that the datasets painstakingly compiled by scientists at the time would be available for future generations of scientists on magnetic tape.

      Yet, just a few decades later, despite the space agency’s best efforts to keep the tapes in a climate-controlled environment, time has left them cracking and brittle. Furthermore, when scientists attempted to re-use some of the data in the late 1990s, they found that they could not decode the formats used. In the end they had to track down old printouts and retype everything.”

  4. ecoquant says:

    Very interesting, John!

    One of the purposes of the Long Now Foundation is to try to preserve basic knowledge for the far future. I saw an early talk where a big concern was that future civilizations might not be able to read our digital file formats.

    On the reverse side, I’ve heard talks by historians and museum curators concerned about the loss of records, like diaries, because people don’t use paper any longer.

    One of them in fact mused that a future civilization might (mistakenly?) consider us to be the Age of Ignorance because there would be no record of writing. Obviously that’s false logic, but …

    I had a Botany prof in college who thought we’d be known as the Age of Plastics. But that was long before it was appreciated that plastics are decomposed by microbes, especially in oceans, but even in landfills. As Dr Chris German from Woods Hole Oceanographic Institution (WHOI) observes, “Microbes don’t spurn a free lunch.”

  5. Peter Erwin says:

    Ptolemy the Fat—”Physcon” —put an end to science in Alexandria in 154 BC with brutal persecutions.

    Well, no. (Leaving aside the fact that Ptolemy the Fat wasn’t Roman, and so doesn’t fit into a narrative of “The Romans ruined Greek science!”) Alexandria recovered and remained a center for science for at least another three hundred years. It’s where Hero of Alexandria (died ca. 70 AD) and Claudius Ptolemy (died ca. 170 AD) lived, and also where Galen (died ca. 210 AD) — the apotheosis of Greek medical science — received part of his training.

    The real question is why Hellenistic/Greek science seems to have stagnated after the 2nd Century AD (i.e., about three centuries after the Roman conquest), and why much of it never caught on in the Latin-speaking West (we know that Romans were interested in it, to the point where encyclopedia-style summaries of Greek mathematics, astronomer, etc., were written in Latin, but it’s striking that there aren’t any notable Roman mathematicians or astronomers, and very few physicians.

    • John Baez says:

      Thanks! Maybe I should tak Lucio Russo with a bigger grain of salt. He writes:

      Starting with the year 212 B.C., which witnessed the plunder of Syracuse and the killing of Archimedes, Hellenistic centers were defeated and conquered by the Romans. During the second century B.C. scientific studies declined rapidly. Alexandria’s scientific activity, in particular, stopped abrubtly in 145-144 B.C., when Ptolemy VIII (Euergetes II), who had just ascended the throne, initiated a policy of brutal persecution against the city’s Greek ruling class. Polybius says that the Greek population of Alexandria was almost entirely destroyed at that time; Athenaeus gives a lively description of the subsequent diaspora of the city’s intellectuals; other sources give a few more details. Our information is not enough to reconstruct the causes of the persecution. Subsequently, Euergetes II continued to pursue a policy hostile to the Greek community in Alexandria, turning to the indigenous ethnic groups for support. Since he had enjoyed Roman support even before ascending the throne (when, exiled by his brother, he had taken refuge in Rome), it is reasonable to think that he became a proxy for Rome’s Mediterranean expansionism, which at the time was particularly violent.

      Rome’s expansion ended in 30 B.C. with the annexation of Egypt, thus completing the unifiation of the whole Mediterranean under Roman rule. This event is usually considered as the end of the Hellenistic era, which was followed by the “imperial period”. From our point of view, however, it is not a particularly significant date: although the golden age of science had tragically come to an end over a century earlier, with the end of scientific activity in Alexandria and the conquest of the other main centers by the Romans, Hellenistic culture survived during the imperial age.

  6. Knowledge of geometry is an interesting case. Newton’s Principia is all geometrical and even Feynman gave up trying to reconstruct the inverse square the way Newton did it (“Feynman’s Lost Lecture” – see page 19: “”Feynman tried to follow Newton’s proof, but couldn’t get past a certain point , because Newton made use of arcane properties of conic sections (a hot topic in Newton’s time) that Feynman didn’t know.” The incredibly detailed knowledge that underpinned Principia has been lost. I imagine that people just lived and breathed geometry and it all made sense. I can recall seeing a physicist re-deriving one of Newton’s fluid least drag problems because he couldn’t follow Newton’s work but he got the same result finally and was suitably impressed at the power of geometry.

    • Wolfgang says:

      This is very interesting, and I think it works the other way round, too. As we do not always know today, what our ancestors did know, it also seems to be very difficult to know, what they did not know. The latter seems obvious, but is far from that. We cannot unlearn things. We cannot really imagine how it must have been in a time preceding the discovery of a method, say calculus. Of course, by meticulous historical study one could reconstruct both knowledge, thereby giving an exact picture of the historical knowledge at this time. But who is able to do that? This means, we will always read Newton’s, and any other historical text, from our perspective, never from theirs, unless maybe we really try very, very hard, remembering the biases in our knowledge. In one way, this is lost knowledge, too, which might not be seen as that, since we think of ourselves to better understand the topic as a whole today.

  7. rovingbroker says:

    “And we shouldn’t count on our current knowledge lasting forever, either.”

    The solution will certainly include a clever combination of 5G and blockchain.

  8. Richard says:

    All this talk of preserving records and that science can be rediscovered assumes that technological civilization can be re-booted.

    With all of the cheaply extractable raw materials gone, and much of the globe uninhabitable, what are the odds that anything will be preserved, or that anything cultural can be recreated in less than geological timescales?

    • John Baez says:

      Many of the cheaply extractable raw materials will be conveniently stored in landfills.

      But, one can also imagine future civilizations that don’t use much more than plant-based materials, rocks, sand, etc., for technology, so don’t have our kind of technology, but still have interesting culture. They might be unable to do particle physics or even quantum mechanics… but there are lots of other things to think about.

  9. “The Antikythera mechanism, found undersea in the Mediterranean, dates to somewhere between 200 and 60 BC. It’s a full-fledged analogue computer! It had at least 30 gears and could predict eclipses, even modelling changes in the Moon’s speed as it orbits the Earth.”

    Is this epicyclic gearing that essentially does this kind of stuff?

  10. John Baez says:

    Nothing that complicated, but it’s fairly complicated:

    (Crosshatched gears are merely conjectured rather than actually found among the fragments.)

    The Wikipedia article gives a pretty detailed description:

    Antikythera mechanism

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