First, we didn't really forget "greek fire" or "roman concrete" exactly. We don't know what the formula for "greek fire" was exactly because it wasn't recorded. But in modern times we have an amazing chemistry and can come up with a hundred formulas for napalm -- we just don't know which of those matches "greek fire". Nothing was lost but the association between a formula we almost certainly know and a name.

Same goes for roman concrete. We know far more about concrete than the Romans did. We just don't bother to engineer everything to last forever, because that costs money and has little point to it a lot of the time. Yes, some buildings are works of art, but many things just have a function to fulfill, which is often temporary. Nobody is sad that the millions of mass-made soviet residential crappy buildings aren't still as good as new. If they were made to a better standard they'd still be ugly cookie cutter things.

And I'd say the same goes for the Saturn V. We didn't forget material science or heat shielding. We launch plenty rockets and even landed car sized robots on Mars -- that required excellent understanding of heat shielding. If we had any reason to build a modern copy, we'd use whatever shielding is required, after accounting for modern improved materials. We wouldn't be dumbfounded that the thing melted down on the launch pad. That in the popular consciousness we see the engines without the asbestos covering doesn't really mean much of anything.

Your comment seems to be about how these technologies aren't useful for us in the present. AFAICT, it doesn't dispute that the knowledge was lost.

An additional interpretation is that you're interpreting my writing as being from someone who thinks that "the Romans clearly built it better" etc.

That's not the point I'm making.

Yes, we have napalm and recipes for it. Yes, we have digital computers that are incalculably better than the Antikythera mechanism. Yes, we can trivially manufacture better concrete.

And that's amazing, for us today, but how much better would it have been if we hadn't forgotten about these technologies in the first place and had continued to improve on them? Heron of Alexandria described building steam engines, what if we had continued to experiment on them for over 2k years? Where would we be now?

The loss in knowledge doesn't matter (as much) anymore in the present, but it has held us back, measurably so. For a thousand years, between the Antikythera mechanism and a few hundred years ago, we somehow lost their equivalent of Kepler's laws, some version of calculus, precision machining, mechanical computing etc. For over a thousand years, we have no records of anyone producing devices that approached or surpassed its capabilities.

What if the knowledge behind that device hadn't been lost and we were 1k years further along into our understanding of mathematics and computing?

That's the point here.

The point is that those technologies were exceptional at their time, but were still lost, and we are poorer for it, because it took away hundreds of years of erstwhile progress that could have been made had we remembered and kept building on them.

Happy to hear how I could make the ending better though!

If you want to make the point that "what if we developed steam power sooner", then sure, that works so long you keep talking about steam power in Ancient Greece. Yes, knowledge did get lost there.

But that's not what happened with the Saturn V. The knowledge didn't really go anywhere. We still have the engines and the designs, they're just technologically obsolete. We're not making them not because it's some lost wonder-technology we forgot how to make, but because it costs a lot of $$$ and there's no profit to be made by sending another lander to the Moon and science funding is scarce. That we don't see the asbestos covers much doesn't really mean anything because the actual knowledge is in the fields of heat management and materials science, and not magazine cover photos.

Just as legacy tech isn’t automatically better than today’s technology, today’s technology isn’t always better than legacy tech. The agency has gone back to the Apollo well many many times for these “technologically obsolete” designs because they effectively solved problems that we haven’t faced in decades.

Example, the CSM’s umbilical connection was a work of art, it had to be reverse engineered from museum pieces for current gen spacecraft, https://www.nasa.gov/mission_pages/constellation/orion/umbil...

The F-1 engine’s turbopump and gas generators had to be taken apart by hand because we haven’t built anything close to their throughput for decades, https://www.nasa.gov/exploration/systems/sls/f1_sls.html

Apollo’s phenolic resin heat shield led to the Phenolic-Impregnated Carbon Ablator (PICA) that was then studied by SpaceX to develop their current PICA-X heat shield.

IIRC, there’s a fairly direct line between the Apollo parachutes and SpaceX, https://spinoff.nasa.gov/Spinoff2017/t_3.html

There are many more big and small examples that I can’t name off the top of my head. From the thermal roll to core sampling, having that knowledge allows us to learn from their experience and do better.

Hundreds of thousands of extremely smart people worked on the program and they came up with some extremely interesting ideas along the way. It’s faster/more useful to have a library of their work to draw from rather than going to the well again and redoing it from scratch.

Consider the massive costs that went into many old structures. Often you could measure them in lives lost during construction.

In the case of asbestos and leaded paint, lives and damage done by having used them.

Now, I do believe we should have people study the past. I still like reading on old programming techniques. But progress is not necessarily held back by not building on what came before.

Or the simple fact that laborers were not paid. Hard to compete against literal slave labor

Servitude labour was more of a thing for castles, Cathedrals were build in towns and cities, with free citizens. Castles were build by nobles and those had servitude populations to draw labour from.

Doesn't exactly sound like volunteering to me.

Me and my s/o, who actually studied a lot of the German cathedrals for her master's degree, went on a tour across a lot of the cathedrals this summer with the 9-euro flat train ticket... it's utterly amazing what medieval people could pull off. If you're interested in old buildings, wait until the successor of the 9-euro ticket comes next summer and go on a trip yourself, it's definitely worth it.

Do you also apply such a standard to modern examples of volunteering?

That said, I think this is just a misalignment in what "volunteer" means. Historically, it was more like "volunteer trees", in that you didn't specifically recruit or hire them. It did not mean that they did not get benefit out of it.

Specifically, if there was a local market, it would have been near the cathedral. And if you didn't have a reliable farm or other plot of land to provide food, seems reasonable to assume your best bet was to be compensated in some form for manual labor.

I believe that knowledge is overrated on the long run. It is methods for knowledge creation what really matters. And incentives to apply the best known methods.

Had you read Bret Devereaux talking on an absence of Roman Industrial Revolution?[1] No practical steam engine before it's time has come. Knowledge is created when it is needed. I believe the same stands for computing. It must be some new demand for calculation that created computing. Probably the development of economics.

[1] https://acoup.blog/2022/08/26/collections-why-no-roman-indus...

You might be interested in Lucio Russo's book The Forgotten Revolution. He describes how the Hellenistic scientific and technical culture which gave us Heron's aeolipile, Greek fire, the Antikythera mechanism, Archimedes' method of exhaustion, Eratosthenes' measurement of the Earth's size, Eucid's axiomatization of geometry, etc.†, was lost. Basically what happens was that when centers of science like Syracuse and Alexandria were conquered by the pre-scientific Romans, the philosophers who weren't massacred were dispersed to the four winds, preserving their knowledge in foreign lands if at all. In later generations, Christian fanatics lynched Hypatia and threw down the Egyptian temples, extinguishing the millennia-long knowledge of hieroglyphics.

Russo reaches some conclusions that aren't generally accepted, but much of the history he reviews in the book is uncontroversial, if little-known — but starkly horrifying.

It wasn't a gradual process of forgetting, but a series of genocidal catastrophes. Similar processes obliterated the House of Wisdom in Baghdad, the Maya codices, the khipu, and in our own time most of the world's languages and folklore, much of the Timbuktu libraries, the Afghan relics of early Buddhism, and the collections of the archaeological museums in Iraq.

______

† I have omitted Roman cement and the separation of gold from silver because I don't have any reason to believe they came from the Hellenistic world.

They're about invasion, shifting power centers, economic collapse, societal decay, religious zealotry, and whatnot.

And indeed, many of the moments where massive progress was made were flukes, not the norm -- very happy coincidences that were unlikely to continue for long.

So the idea that we've lost progress due to "forgetting" makes as much sense as saying that a company shut down because the engineers forgot how to work with the codebase. No -- it was all about much larger events. The forgetting was a result, not a cause.

So thanks for that.

The act of preservation in the now, making copies etc. is kind of like a prophylaxis against an adverse event. We are doing the mundane to prepare for the insane.

Let's consider the problem of media longevity — while, as you point out, it is not by itself sufficient to preserve knowledge, it does seem to be necessary, at least as we currently understand things. (Scholars of songlines may disagree, but of course oral traditions like songlines are even more vulnerable to catastrophic forgetting; even half a century of prohibition can obliterate them.)

If you preserve data on Flash, you need to refresh it every few years before the stored electrons leak away; standard datasheet retention times are 10–20 years, though presumably that's at 80°, so maybe you'll get a few centuries at room temperature. If you can trust in continuity of institutions, this is not a big problem; you just have an endowment sufficient to support a small number of sysadmins who make sure the SSD arrays get resilvered at the right interval, replace broken devices, etc.

But if your preservation medium has to survive the PRC nuking TSMC 18 months from now — or an invasion by a military dictatorship of genocidal religious fanatics who hunt down and kill the sysadmins and burn the archives, as happened with the Maya codices — Flash looks much less appealing (though perhaps still viable; see http://canonical.org/~kragen/eotf/ and https://dercuano.github.io/notes/atmospheric-pressure-harves...).

— ⁂ —

I think this also bears on the question you're focusing on in the post, which as I understand it is more a question of curriculum design than of preserving physical storage media. If the target audience for the curriculum is the next generation, or three generations down the line, you can assume a lot of shared cultural background: shared celebrities, shared neologisms and modisms, shared values in a lot of ways. Hipparchos, by contrast, was writing for Ptolemaios, though he didn't know it. He died in 0120 BCE, and Ptolemaios was born in 0100 CE, 220 years later. Hipparchos was the most recent astronomer he could find to cite in the Almagest.

Amongst the civil warfare of the late Ptolemaic dynasty, none of the succeeding eleven generations had produced new astronomical observations, and the line of philosophical mentorship was broken, at least within the Hellenistic world. This bears quite directly on the problem of lost tacit knowledge you focus on in your post. Even Hipparchos was only able to do his work because he lived in Rhodos, on the periphery of the Alexandrian scientific world, which was sacked by Cassius in 043 BCE after a century of gradual reduction to servitude by Rome.

How do you design a curriculum so that it is still intelligible after eleven generations of cataclysmic cultural collapse, largely under a prescientific genocidal military dictatorship like that installed by the Roman invasion? The solution might look more like the Rosetta Project or the Cult of the Bound Variable and less like Surely You're Joking, Mr. Feynman. If Hipparchos had done a better job, maybe Ptolemaios (and consequently Colombo) wouldn't have gotten the size of the Earth so badly wrong. Maybe Ptolemaios, like Archimedes before the Romans killed him, would have followed the heliocentric model Aristarchos had developed 500 years before him (though Hipparchos did not.)

One of the things I really like about the work that the Long Now Foundation has done and does is that they've defined their threat model and retrieval requirements with precision. They're okay with things being inconvenient to retrieve in the short term as long as they can be retrieved by beings with extremely different tooling in the long-term.

I think depending on the model, the threat form can change. The implicit assumption that I was thinking about while trying to come up with a "solution" (I did emphasize that it's a solution, and not even a good one at that, just my stab at it) was that the information would be for the world of 2070. Or, 2080.

I chose that for two reasons, one was that a lot of people have done long-term things, and depending on how long-term you go, you start getting into really interesting territory. And the second is that there's a need to start from a positive place/assumption (i.e. it's implicitly baked in that our civilization will still be around and kicking at said time without a catastrophic collapse) to make it more relatable for the reader so that they're likely to do something. Even if that something is a half-hearted attempt at documenting their personal projects with a higher degree of fidelity.

Depending on the threat model, the following would change,

    - the information encoded/form of encoding

    - how many copies would be necessary

    - maintenance specs 

I don't have the answer to the fascinating question that you've mentioned. I need to think about it more and we should continue this conversation. Lemme know how I can connect. I'm available via twitter etc. (see profile)

And will do :)

I agree with you point. On the other hand I think if we did not forget anything and kept improving while still having medieval views we might have had exterminated ourselves already.

Dead from climate change most likely.

I don't think this is a possible world in the first place. The knowledge of steam engines and intricate mechanical machines wasn't "lost" by accident: it was lost because there was no good reason to develop it further. The Greek steam engine was a cool demo, neat little piece of stage magic for the temple whose doors it powered, but there weren't any practical applications in sight. I bet it also was a hell of a maintenance burden.

The unfortunate reality of our lives seems to be that technology only propagates as long as there's enough funding for it. That means at least several people have to need it very much to support a single inventor. Many more people if there's a need for extra labor, or expensive resources (such as metals). That's as true today as it was 2000 years ago.

What I'm saying is: the reason the Greek steam engine was forgotten is that there was no demand for it back then, and that's because of a combination of factors, such as:

- It could do only so much, because other important technologies - such as precision manufacturing - weren't in place;

- The things it could do could be served better and cheaper by other means - such as hired, slave[0] or animal labor;

Learning history on my own[1], past the school curriculum, I was surprised to discover that a lot of technology was always there in the background. Medieval times weren't just a long period of stagnation - it's when the building blocks for industrial evolution were slowly invented. A lot of important developments happened in mining, where increasingly powerful and reliable pumps allowed people to dig deeper. The progress here was sustained, because it was paying for itself.

The industrial revolution happened when things aligned just right. The steam engines could be manufactured cheaply and robustly enough, and put to important enough work, that they paid for themselves - which financed their improvements, which opened more net-profitable applications, and so on - creating a positive feedback loop that run so long, it triggered more feedback loops, and turned humanity into proper technological civilization.

Note that there's a lot hiding in the "put to important enough work". The overall political and economic situation of the era was what created the "jobs" for steam engines, and that situation is downstream from technologies developed for sailing (progress in astronomy, healthcare and shipbuilding), communications (the printing press), and many others.

Point being: inventions aren't islands; they can't sustain their existence if there isn't a need for them. The question "where would we be if we didn't forget ${technology that we 'forgot' and 'rediscovered' centuries later}" doesn't seem valid to me.

----

[0] - There's an argument I see raised every now and then that historically, technology made jumps when labor was expensive; conversely, cheap labor meant it was cheaper to just throw more bodies at any problem.

[1] - I'd like to say "studying history", but what I really mean is just occasionally watching some high-quality documentaries and reading blog posts by people who (claim to) know this stuff.

I'm not personally convinced of the specific proposed solution, since it's "Just Another Technology", but I wholly agree that the problem exists, and I think you argue effectively for some of the reasons why.

In more ancient times, the process control instead basically relied on "get your ingredients from this well/mine/whatever". So while we actually have a decent idea of what Greek fire is (it's a kind of napalm), we don't have any way of knowing what their actual source of naphtha was, so we don't know what the precise impurities that gave it its best kick were. (I'll also opine that there were probably several different formulas in use, and we may be ascribing properties of different kinds of Greek fire to the same one, which would mean that the search for "the" formula for Greek fire could only ever be a failure.)

This ship-borne version only worked in calm conditions, otherwise fireships were just as likely to set themselves on fire. However, it did do pretty well in the sheltered Sea of Marmara around Constantinople. The fireships probably saved the empire from the Caliphate during the 719 siege of Constantinople by destroying the much large Muslim fleet. That occurred at a nadir of Byzantine power and the height of Caliphate power. Western Eurasian history would have looked very different if the Caliphate got control of the Bosporus then, as opposed to the Turks 700 years later.

That is, it is an odd blind spot to not realize that "barely exceeding the goal" is often far far harder than over building.

Grossly overbuild the structure, so that it is lightly stressed. Don't use any reinforcing material within the concrete (much of the damage that happens to a modern reinforced concrete structure is the result of the internal reinforcement swelling due to corrosion). Ensure that the structure doesn't freeze (water that penetrates the concrete and freezes will cause cracking).

Note that following these limitations would rule out the vast majority of modern concrete structures.

Part of the problem is "ancient Roman concrete" is the epitome of selection bias. We basically know why it's strong, and can basically recreate it, but it would take a very long period of process optimization and corrosion testing to get a consistent product we're sure has a long lifespan.

If you want something to last 1000 years, you may be better off cutting it out of a hard, stable stone (like granite).

How long? 1 year? 10 years? 100? 1000?

If it's not the last option, isn't it worth figuring out?

Actually, you don't have to imagine it. Go watch the show, "Peripheral". This idea of long-lasting concrete was actually what I found myself thinking about just last night watching it, in the scenes of future London.

Or is the tailoring of the mix to the environmental conditions going to be a more significant factor than the components?

There are actually lots of artificial materials that weather more slowly than rebar-reinforced portland-cement concrete. But buildings are huge — a small house commonly contains many tons of building materials, and a large building contains thousands of tons — so the overriding consideration for building materials is that they be cheap as dirt.

In fact, buildings — then and now — are to a very large extent literally made of dirt. And rocks. Bricks? That's clay, which is a kind of dirt. Mortar? That's sand, which is a kind of dirt, glued together with typically a small amount of ordinary portland cement with an even smaller amount of additives. Drywall? That's gypsum, which is the kind of dirt White Sands National Monument is made out of (as well as, in its mineral form, many stunning ancient Egyptian vases) although a significant amount of modern gypsum is sourced from flue-gas desulfurization. Plaster? That's sand glued together with cooked gypsum, except when it's sand glued together with quicklime, which is made by cooking chalk. And of course adobe is sand glued together with unfired clay.

The issue is that costs that seem totally reasonable when you're dealing with gram or kilogram quantities of a material become totally unmanageable when you need a hundred tonnes of it. You can use glass, wood, or steel (the cheapest metal) in more modest amounts, but they generally can't replace OPC.

So, there's a pretty short list of materials that are both strong enough and cheap enough to use as building cements, and which can additionally be synthesized on a building site between grains of sand (as opposed to, say, in a furnace isolated for oxygen, or at 500°). You have:

· the above gypsum, quicklime, ordinary portland cement ("OPC"), and unfired clay;

· tar (asphalt);

· geopolymer cements (milled metakaolin polymerized with waterglass);

· waterglass itself;

· Sorel cement (magnesium oxychloride);

· magnesium oxysulfate;

· calcium aluminates; and

· the phosphates of aluminum, magnesium, and occasionally calcium or even zinc.

Of these, some have worse weathering properties than OPC: unfired clay, Sorel cement, magnesium oxysulfate, and (if cured improperly, in a famous nationwide disaster in Spain a few decades ago which wasn't discovered for years) calcium aluminates.

But there are all kinds of extremely stable materials that would last much, much longer than concrete in the weather, but which are just too expensive to make buildings out of, or which nobody knows how to make big enough pieces of. Soda-lime glass (though foamed glass and fiberglass have uses), aluminum, titanium, aluminum bronze, epoxy "granite", gold, silver, polytetrafluorethylene, sapphire, yttria-stabilized zirconia, yttria, carborundum, silicon, the rubber used for car tires, and so on.

Raise the bar and use diamond.

I used to be in the CVD diamond world. On my honeymoon nearly 30 years ago, my wife and I were hiking in the Himalayas, in Sikkim.

My Dad loved diamonds and used them in his work (geophysical drilling, using diamond bits). He passed a year before my marriage. I wanted to leave a rem meminisse eum a in his honor.

So I grew a 2mm thick x 2.5cm diameter diamond disc. I used some nucleation art to make his first name appear as a texture variation in the faceted growth surface. I left it on a protected ledge at ~ 19,000 feet, with a note that just said “Thanks, Dad”.

That disc, or its fragments, will be around until that mountain gets covered by a lava flow or subducted into the mantle.

Concrete? A thousand years? Let's aim higher. :-)

Structures that lasted from ancient times to today were either made out of giant slabs of stone or had maintenance done on them repeatedly over the years.

Unfortunately...

1. There's no "we". i.e. the entities choosing concrete mixtures and other construction technology do not typically share interests with the people / organizations which inhabit the buildings, except in some very abstract roundabout sense. Which is part of the reason why

2. Concrete construction is usually not engineered to last even a few centuries, let alone "forever". In fact, it is often so poorly engineered (or one might argue: misengineered) that it won't last even a single century, or less than that. Because the principle of costing less money tends to be taken all the way to the point of just barely passing regulatory constraints.

3. ... and those regulatory constraints are often quite lacking. I live in Israel, and a constructor is not even required to guarantee that their building will not-collapse beyond 7 years' time.

4. Actually, a lot of the mass-made soviet-era residential buildings are very well made and almost as good as new (well, considering how they often weren't so great when new). This depends on the specific country, region, period of construction etc.

Practical Engineering has a good video on Roman concrete

https://www.youtube.com/watch?v=qL0BB2PRY7k

Yet still better than US suburbia.

The context of when and why (and to who) asbestos causes cancer is simply ignored.

This sort of problem exists everywhere. If something bad happens or is caused by something (politics, economics, etc) we are simply too quick to throw the baby out with the bathwater.

From a tech standpoint, I see this a lot. Postgres at my current company got banned because one team one time had a bad experience with it (after they misused it).

Imagine if when building a house you needed to shape every single brick for it’s actual load. Sure you end up using less materials, but you lost economies of scale and suddenly need vast quantities of computing power for minimal gain.

Using uniform bricks and banning stuff may seem wasteful, but it enables efficiency elsewhere.

Rather than focusing on the safe use of a material, we instead lean towards removing it all together. Older materials with known faults (such as wood being flammable) are deemed acceptable simply due to having known weaknesses in a period where we didn't care about safety. If we found out wood causes cancer, we'd still use it in building and furniture because we've always used it in building and furniture.

It's not an economies of scale problem.

When you get right down to it, the people that got mesothelioma from asbestos pretty much universally directly worked with it (usually in the form of doing things like blowing it in loose form for insulation).

Yet we spent an ungodly amount of money and time stripping asbestos from buildings that had been there for decades not causing any problems. Ironically, directly exposing people to asbestos in the process (more than you'd ever be exposed to it was left undisturbed).

Asbestos is only prohibited where there are practical alternatives.

The problem with asbestos is it was used where there was no rationale for its use beyond profits as a bulk material.

Those profits were only available because the health costs were externalized.

The existence of practical alternatives is the reason asbestos abatement is possible. The cost of abatement is almost entirely the removal and disposal, the cost of replacement materials is not a major factor.

If you have to do such a thing every time you are rebuilding something it is not going to economic.

That's not all or the only way asbestos can be packaged. Which is my point. If you bind asbestos to vinyl, for example, you get a lot of the same insulation benefits with none of the problems of becoming a health hazard.

That's the problem. Yes, loose blown asbestos IS a problem and a major health hazard, but it's not the only form asbestos can take. Hence, baby thrown out with the bath water.

Maybe asbestos binded to vinyl is literally not a health hazard in any of these cases, but this needs to be shown in a positive way. The reason it's regulated/nearly banned is because the default way we treat materials is that they are assumed safe until data shows otherwise, and we obviously can't treat asbestos as a default material.

Wear a mask. But also, you likely aren't going to be affected. The risks are primarily for people working heavily with the stuff. Similar to how you could get silicosis cutting concrete but you likely won't get silicosis because you don't do that enough daily.

> if the house catches on fire

The neat thing about asbestos is it doesn't burn. That being said, the fumes from a fire are toxic without the asbestos so it's not exactly like it's making it more dangerous. (perhaps cleanup is what you're referring to?)

> or floods

Getting asbestos wet keeps it from Aerosolization. In fact, it's recommended to do that anyways if you are removing asbestos. (though, water isn't good enough to make it completely safe, it's better than nothing). [1]

> The reason it's regulated/nearly banned is because the default way we treat materials is that they are assumed safe until data shows otherwise, and we obviously can't treat asbestos as a default material.

The reason it's regulated/nearly banned is because the asbestos industry hid the dangers of it and got exposed in a very public way which generated heavy public outcry. We treat it like this not because it's rational, but because of public outrage. Asbestos has become synonymous with unsafe, no questions asked. [2]

Mercury and lead have similar more well known public health problems, yet purchasing CFLs and lead water pipes remain everywhere. Why? because there's not nearly the same level of outrage.

[1] https://www.hse.gov.uk/pubns/guidance/em5.pdf

[2] https://www.asbestos.com/featured-stories/cover-up/

I recently learned that in the mid 20th century there was a huge scandal when it came out that TV game shows were rigged. The public was outraged and a law was passed prohibiting the fixing of "purportedly bona fide contests of intellectual knowledge or intellectual skill". You can go to prison for up to a year for this.

Because we need to be protected from that. ( https://www.law.cornell.edu/uscode/text/47/509 )

Fixing a purportedly bona fide professional wrestling match was and remains completely legal, of course, because that's not a contest of intellectual skill. Fixed quiz shows are a scourge upon the public, but fixed sporting events are just good fun.

It’s just not worth having in any building you want to ever make any alterations to… And the only reason to have it would be just to have the same insulation value with a slightly thinner panel than what we’ll replace it with!

There's nothing special about old buildings requiring compromise. Asbestos is just particularly costly. It sucks, and often it's more benefit in the long run to just rip that band-aid off now rather than live with suboptimal compromises for decades to come.

If the rate was high enough I bet we'd phase it out. Don't underestimate the importance of the size of the effect.

I dare say, wood smoke has caused more cancer than asbestos ever did. [1]

[1] http://www.familiesforcleanair.org/wood-smoke-pollution-kill...

And there are whole programs designed to reduce worldwide deaths from smoke, precisely because it is a major problem. It's something we're actively working on because it's so serious and plausibly fixable.

So what on earth are you trying to say?

Your link is talking about indoor fires. Outdoor fire pits wouldn't concentrate the smoke in the living area. I have no idea what the total effect would be for outdoor fires, but it isnt' the same as the indoor burning biomass stoves

wood burning stoves are absolutely required to be updated now with certified emissions stoves. all four wood burning stoves/fireplaces in our cabin had to be replaced before we could finalize the purchase. also it would have been considered uninsurable if the stoves were not updated to meet the new wood burning standards.

these weren’t like antique stoves either, if i’m remembering correctly they were new in like 2000ish.

honestly, the region of our cabin is noticeably more pleasant to be in since they started requiring this—when i used to go there as a kid, the air was just awful to breathe when everyone was using the previous gen wood burning fireplaces.

We (the US) still allow asbestos in certain scenarios in an attempt to keep the baby and the profits. https://www.maacenter.org/asbestos/products/. Talc especially has had a lot of attention in the last year or so.

I think there is also a pretty big difference between how people view a material with undesirable qualities such as electric causing fires, or wood being flammable, compared to asbestos damaging the individual.

Very few scenarios allow it and there's active lobbying to remove it even in those usecases. The guide you linked to primarily cites old products still in circulation and not new products.

Yeah, cause they often (as I understand) were not using proper protective measures to keep from inhaling the dust particles. A common thing I have seen on construction sites of all sorts, is the workers refusing to use some thing or the other, because it makes them uncomfortable, or harder to see (but still can) or harder to breath (but still can) or some other jackanapes idea like that.

> Yet we spent an ungodly amount of money and time stripping asbestos from buildings that had been there for decades not causing any problems. Ironically, directly exposing people to asbestos in the process (more than you'd ever be exposed to it was left undisturbed).

This is where things get real fun. When moist or absolutely damp/wet, asbestos is basically harmless (to the lungs) because it's almost impossible to breath it in at that point. If you somehow manage to breath that in, you have to basically be trying to do it. When it is dryer than chalk on a hot summers day with 0% humidity though, then yeah it can cause all sorts of problems. But even then, people removing it tend to do the thing that the other prior mentioned construction workers (often) won't do.

They wear gloves, have masks on; and even are running some form of proper ventilation. And so much of the issue is averted.

Then comes the media and government. They take edge case scenarios like these, and hype them up; whilst mixing in the prior construction workers into the data. This makes things look worse than they really are.

It's not just Asbestos you can find this sort of thing with them. You can find media and government doing this with many things if you look carefully.

But that being said, none of this is to say that Asbestos isn't a problem at all. It's just to say that Asbestos gets the treatment it does for the same reason we have warning labels on nearly everything.

We placate and protect the stupid... stupidly.

And for what? In 99% of the uses of asbestos domestically and commercially there are safe products that can do just as good a job, perhaps just requiring things to be slightly thicker to get the same insulating value... Sure there are some niche industrial and scientific applications where it's still potentially the best performing option but so much of what it was used for, it just didn't need to be...

I make plenty of comments knowing people will downvote them based on content and still ended up so much positive karma it would take serious effort to burn it all.

So, sorry, but while I didn't downvote you, I do disagree with you; entirely. Validly.

https://github.com/minimaxir/hacker-news-undocumented/issues...

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> TL;DR: apparently this can happen due to an account being "rate-limited". Rate-limited accounts can post a max of five posts within 24 hours.

See : https://hn.nuxtjs.org/item/15507821

Specifically this bit:

dang 1018 days ago

That's a sign that your account is rate-limited. We rate limit accounts when they repeatedly get involved in flamewars or regularly break the site guidelines or post lots of low-quality (for HN) comments. It's a crude tool but one of the few we have to prevent such things from overrunning the site.

The thread also has interesting discussions on other mod tools: shadowbanning, IP bans, and the like.

Apparently the way to un-rate-limit an account is to send in an email and mention that you will "stick to civil, substantive comments that scrupulously follow" https://news.ycombinator.com/newsguidelines.html. Some amount of convincing prostration may be required, as a sort of high-level turing test. There does not seem to be a way to do this while not giving away your email address (which was not required at signup).

The moderator mentioned something about repeated, human-written warnings before rate-limiting, but this does not seem to be the case now (2020) - rate limiting seems to be a milder, less-known variant of the shadowban.

________________

Downvoting, flagging, and moderator actions are three different things.

Posting something people disagree with isn’t the same as a flame war. Keeping things civil is a requirement, which trips people up.

Prior to that, I wasn't rate limited. After that, I was. Make of it what you will.

I'll still use it to see what people think, but that's about all its good for in the comments section now; just like Reddit, Twitter, and others.

But at least the links are still interesting.

P.S. I'm mostly only commenting still right now because

A: I haven't made my decision yet and

B: It would be rude to ignore those who did reply to me kindly.

You could (for instance) argue that once the product exists, and is in place, it poses no further risk to anyone - this is a common suggestion but is demonstrably, dangerously false. It’s a rock, it never breaks down. Its state never changes over mortal timescales. Eventually a building, or a rocket, or a train will be refurbished or scrapped - and when that happens people in the area are at no less risk than they ever were.

It could even lower the net asbestos on earth :) (not /s, though I attempting to add humor)

Plus toxic materials are very much still in use in the space industry, including asbestos. They're used as separators in fuel cells, insulation for missiles, etc

Asbestos was banned for buildings not for the space industry. https://www.pbs.org/newshour/show/decades-after-proof-of-its...

It will be replaced slowly as better materials become available.

And, to be fair, if you could use aerogels, you should use aerogels. They are way better at insulation than asbestos. They are simply cost prohibitive in most cases.

Despite what it may look like, I'm not trying to shill for asbestos :D. I just think it's a microcosm of a problem with society.

Asbestos was widely adopted because it was a very cheap material, they did know that it was dangerous but that fact was hidden by the companies selling asbestos containing materials for profit. There is no reason to use it.

Not only asbestos, for example in the past they used to put radioactive material in daily life object, such as clocks, dials, etc to illuminate them in the dark. Obviously it was not a good idea, since the risk it poses didn't justify the purpose. Same thing with smoke detectors, now we are no longer using radioactive particles in them, basically because we have better electronics that not only can replace radioactive material but can be more effective in detecting a fire.

The author's point being we not only purge it physically, but also culturally and thus intellectually. (I feel like there's a meta point around this thread being de-railed by discussions about how bad asbestos is.)

In IT we see this when information is lost (no backup policy), or information is leaked (no security policy). Using technology with no policy/process is almost always a risk factor for business. If said posts team had created a policy and process it's very likely the incident would not have occurred in the first place.

With products control is very rarely tightly held. There is a supply chain from where it's mined out of the ground all the way to destruction of the product which may be decades or even centuries away. Trying to ensure that your customer use a product intelligently over that long of time frame is too risky for most businesses.

Except you can. The Toyota Mirai is available and quite heavily subsidized. Whether buying one is a good idea is a different question, although the main issues with owning one don’t involve safety as far as I know.

with public health risks, strong reaction is absolutely fine, and I wish we had more tendency towards it, not less. let’s do something drastic about micro-plastics!

That's not a way to run health policy. I'd certainly like more action against PFAS, for example. At very least, more science done to know exactly how harmful it is (especially given how it's permeated so much of the public drinking water).

But, would I ban PFAS all together? Heck no. Rather I'd want to have a better understanding of where they should and shouldn't be used and how we should treat PFAS chemical outputs.

https://www.propublica.org/article/asbestos-poisoning-chemic...

https://news.ycombinator.com/item?id=32980712

https://web.archive.org/web/20121022215630/http://www.epa.go...

> EPA does NOT track the manufacture, processing, or distribution in commerce of asbestos-containing products. It would be prudent for a consumer or other buyer to inquire as to the presence of asbestos in particular products.

I don't think this has anything to do with the OP. It is focused on the process of knowledge being lost simply through the raw fact that nobody remembers it. This is applied to everything:

> We have lost more than 50% of all feature films made before the 1950s

The message of the piece is that we've forgotten the asbestos because, when you go to look at the preserved rockets today, it isn't there.

...probably because it was removed for aesthetic and health reasons.

There is actually a good reason for this: the slippery slope is not always a fallacy.

Shocker, that's slow.

We understand this deeply when it comes to software architecture where encapsulation and information hiding are fundamental principles but it applies everywhere. There is a value in not knowing, or not needing to know, because it frees up brainpower for other stuff.

/s

(One of the problems the US has in manufacturing is the loss of a culture where more people have a clue about a manufacturing plant works.)

For most of my life I didn't even think that we were still at a stage where we could lose valuable knowledge.

But it clearly is everywhere, including basic everyday technology such as Electronics, Software, Wood working or even Cooking.

My gut feeling is that the knowledge loss that occurs at every generation is non-linear depending on the field, but it is higher than 75% overall, and probably more.

The loss rate could be reduced by increasing healthy lifespan.

[1] https://www.youtube.com/watch?v=ZSRHeXYDLko

[2] https://news.ycombinator.com/item?id=19945452

[3] https://news.ycombinator.com/item?id=25788317

No data translated from one medium (brain) to another (paper) and back (brain) is 100% efficient.

But documentation is not only 'tutorials' / how to do something.

Documentation is also 'design' / what to do, 'requirements' / why we're doing it, 'changelog' / why we are making the tweaks we are making in the process.

I'm enough of an antiquarian to be interested in why the phone guy who installed the phone lines for the theme parks did what he did...turns out burying the phone lines directly in the dirt was for a particular reason (cheap / good enough) and for decades, it was indeed good enough. But because nobody read the roll up paper showing the phone line runs, the lines were destroyed when someone came along and installed a roller coaster with a greater than 180 degree turn in that spot, cutting the bundle. The documentation wasn't missing data, but the humans failed to read it.

We do forget things all the time, sure. But don't blame documentation when humans don't read it. The weakness in the system are humans, always.

Now is not the time to give up documenting things. All salutes to the ongoing flamewars over 'code should be self-documenting means I never have to write AnYtHiNg down' aside, someone said civilization advances by the number of things we can write down...because we only have so much wetware / RAM / brain space.

Someone said this and I'm stealing from them: under similar conditions, the wimpiest charcoal on the flimsiest napkin lasts longer than the sharpest mind.

In this knowledge-based industries, no matter our particular focus, we individually would be served better by improving our communication skills, namely documentation of more than just the brittle business processes and API interfaces, but the who/what/when/where/why of what we're doing.

This has become more and more apparent to me over my career. Having a document that describes the steps to get to the end product is not useless per se, but it lacks context.

Anyone coming in anywhere from 6 months to 6 years later could maybe reproduce the steps, but anyone who has considered such problems at all would realized that rote reproduction doesn't get very far.

What your future self cares about is how and why you came to the end you did. Why did we use an unsigned int here instead of signed? Why is the field exactly 13 bytes?

https://www.thedrive.com/the-war-zone/39537/the-air-force-ne...

https://en.wikipedia.org/wiki/Fogbank

https://en.wikipedia.org/wiki/Gorilla_Glass

https://en.wikipedia.org/wiki/Friction_stir_welding

We can perhaps create sufficiently close replicas, which may work well enough, using very different technologies.

It doesn't help us understand how much important knowledge was lost by the people who really should know how to do it. It seems like SpaceX is doing okay?

Boeing learned this the hard way when they opened up that plant in SC. Institutional knowledge can't always be replicated.

---

For a very different example, look to older satire groups like The Goon Show or Firesign Theatre or Monty Python. Monty Python may not be old to some people reading this, but try to explain some of the things they were making fun of. Many of the sketches are timeless, but many are very 'of their time'

Mix legacy/GNU/BSD/*box options if you'd like to ruin relationships.

I googled it, assuming he was talking about this: https://upload.wikimedia.org/wikipedia/commons/4/4d/Space_Sh...

because for me this is the standard image of a space rocket. I don’t recall ever seeing a picture of the Saturn V, but perhaps this is an age thing?

Asbestos causes a very, very nasty cancer - mesothelioma - that causes almost certain death. Painful death. With a very bad prognosis. And mesothelioma is caused mainly by asbestos.

There's a reason why we purged asbestos. No one wants to get mesothelioma.

https://www.cancer.org/cancer/malignant-mesothelioma/causes-...

The main risk factor for pleural mesothelioma is exposure to asbestos. In fact, most cases of pleural mesothelioma have been linked to high levels of asbestos exposure, usually in the workplace.

Note that talc is a mineral crystal/fiber a little like asbestos, and talc is connected to ovarian/uterine cancer. Let's not play around with dusty tiny pieces of rock, they seem to be bad for our bodies.

As the insulation was applied at the very last step, there aren't many photos of the final product. Add the presence of the cancer-causing asbestos, none of the existing displays and museum pieces show this vital component.

Because the museums don't reflect this fact, it doesn't exist in popular culture. And because it doesn't exist in popular culture, and that the people who built the Saturn V are dying off, we are largely in the process of forgetting what the most famous machine of the 20th century looked like.

The point of the piece is the forgetting. Not the asbestos.

If it helps, other parts of the rocket were coated in asbestos too, btw. The Reaction Control System had asbestos, https://ntrs.nasa.gov/search.jsp?R=19730017174

And many, many other parts, including the cabins, https://www.smithsonianmag.com/air-space-magazine/a-saturn-v...

Here's a report for the command module, which starts with a very funny quote, "The JSC Director waived the use of the International System of Units (SI)for this Apollo Experience Report because, in his judgment, the use of SI units would impair the usefulness of the report or result in excessive cost." https://ntrs.nasa.gov/api/citations/19740007423/downloads/19...

https://steelcityelectronics.com/2017/02/07/powerhouse-museu...

(Not my pic, just one I found on DDG that fits with my memory of it)

As a cultist, I recall a similar story to the Fogbank one about the fuel pumps for thoe F-1 motors. Apparently in spite of having all the docs, we still needed to reverse engineer them from museum pieces to find out how to build new ones:

https://arstechnica.com/science/2013/04/how-nasa-brought-the...

Why was NASA working with ancient engines instead of building a new F-1 or a full Saturn V? One urban legend holds that key "plans" or "blueprints" were disposed of long ago through carelessness or bureaucratic oversight. Nothing could be further from the truth; every scrap of documentation produced during Project Apollo, including the design documents for the Saturn V and the F-1 engines, remains on file. If re-creating the F-1 engine were simply a matter of cribbing from some 1960s blueprints, NASA would have already done so.

A typical design document for something like the F-1, though, was produced under intense deadline pressure and lacked even the barest forms of computerized design aids. Such a document simply cannot tell the entire story of the hardware. Each F-1 engine was uniquely built by hand, and each has its own undocumented quirks. In addition, the design process used in the 1960s was necessarily iterative: engineers would design a component, fabricate it, test it, and see how it performed. Then they would modify the design, build the new version, and test it again. This would continue until the design was "good enough."

Further, although the principles behind the F-1 are well known, some aspects of its operation simply weren't fully understood at the time. The thrust instability problem is a perfect example. As the F-1 was being built, early examples tended to explode on the test stand. Repeated testing revealed that the problem was caused by the burning plume of propellent rotating as it combusted in the nozzle. These rotations would increase in speed until they were happening thousands of times per second, causing violent oscillations in the thrust that eventually blew the engine apart. The problem could have derailed the Saturn program and jeopardized President Kennedy's Moon landing deadline, but engineers eventually used a set of stubby barriers (baffles) sticking up from the big hole-riddled plate that sprayed fuel and liquid oxygen into the combustion chamber (the "injector plate"). These baffles damped down the oscillation to acceptable levels, but no one knew if the exact layout was optimal.

Now... most of my memory for rockets is from when I did space camp way back in the mid 90s. So... Yeah, I don't have picture perfect memory of that.

This just feels like when I'm told that CS majors don't learn about the involvement of women in computer science. By and large, that is not totally accurate. It is accurate enough for the point, which is that there is sexism. But, as the software person in the room that went to college, I was almost guaranteed to be the only one that knew the names of the women that our education supposedly skipped on.

There are dozens of us!

I wrote this because I couldn't find anyone else addressing it.

Forgetting the Thermal Protection System (that included inconel and asbestos) is a lot harder to read than Forgetting the Asbestos.

And I didn't think it would be a problem. Usually on HN, people read the article before commenting.

1) I read your comment before the article

2) Despite feeling pretty familiar with the subject matter, I don't think I know what inconel is

It was you comment that led me to commit to reading the article, because I'm not interested in yet another article about asbestos but I am interested in the Thermal Protection System.

Sample size of one, but, you know.

To suggest I didn’t read the article is in bad faith. I did read it, and quite liked it as it happens (I had no idea of the extra heat shields over the engines and how that detail had been lost to time). It just could’ve done without the clickbait title is all.

The problem is the geology of many talc deposits. Anywhere talc has formed metamorphically, it naturally co-occurs with asbestiform minerals. [1]

As a result, talc mined from these sources is unavoidably subject to asbestos contamination.

[1]: https://pubs.er.usgs.gov/publication/70027257

In undergrad, we used it frequently in organic chemistry for thermal reactions like sodium fusion.

We don't see it being installed in places where it can be easily inhaled. But it absolutely still has uses.

New industrial projects don't use asbestos. Existing installations are replaced with rockwool, fiberglass or kaowool once it need replacement.

Your undergrad professor wasn't up to date. Kaowool is a drop in replacement.

https://www.youtube.com/shorts/pzfTz-tIbTY

Really terrible if you think about it.

The factory contained an automated production line, about 100m long. The first step was a room into which the raw asbestos fibre was blown. From there it went into the main machine. The door to the room had a glass window, through which the "snow storm" inside could be seen.

One of the old hands in the factory related a story whereby new people would be locked in the room and their mates would crowd around the window to watch the snowman show.

A lot of the people I knew from that company died from mesothelioma, including the person who told me that story. (My relative was not one of them.)

The upper echelons of the company knew the true risk (as it emerged later) but it was downplayed, within the company. Most of the workers truly believed that the risk wasn't that great.

Read old stories, and you can't help bumping into some very different worldviews.

Is placing asbestos around the rocket engines a fabricated example with photoshopped images, or is the description of the design process behind the actual images fictional?

Same with technological information. The way you keep information is by doing things. You bet that we won’t forget how to make bricks, because a lot of people in a lot of factories make bricks every day all around the world. The Saturn V was a white elephant and once the special circumstances which made it viable has ended people forgot how to build it. Who cares?

If someone wants a rocket they can design one for themselves. And turns out, they do. And those newly designed rockets are better for them. Not better in some tech spec sense, but better suited for the task they want it for.

There were made with a singular purpose and everything else was sacrificed to that purpose, even the health of us all.

I would argue that DNA has done an admirable job in this regard and I would deem it successful at capturing and preserving complex knowledge for future transmission.

I enjoyed the post and enjoyed its thought provocative stance. I feel like recording the “why” is important, not to facilitate recreating a given “thing” but rather to help our future creativity by staying aware of past inspiration triggers.

Because someone taking through a problem informally always reveals something that wasn't clear in text/literature.

Anything from DIY projects to tech to cooking, it's always something important

https://youtu.be/bSP03BE74WA?t=165

which depicts a typical American setting.

We have a lot more transparency and insight today (in part thanks to the advancement of modern technologies like the Internet) and Germany has matured beyond being a direct pawn in an international conflict (in part because the US won the Cold War and Russia is politically irrelevant in the grand scheme of things). But projecting the current state (and the public perception of it) back on the Cold War era is ahistorical.

Did you forget the purge of leftist (not just Soviet-aligned) organizations both under McCarthy but well into the Civil Rights era? The US participation in the Vietnam War, which was protested worldwide not just in the US? The Cuban Missile Crisis? I realize many of these events were perceived very differently in the US but from the POV of a country stuck right in the middle of the two world powers the US was just as likely to pull the trigger (or provoke the other party into doing so) as the Soviets.

The Cold War was decidedly not a "just war" (unlike WW2, arguably) but a power play between two nuclear super powers continuously threatening to end the world as we know it at a whim. The fear of nuclear annihilation is why there's still a strong bias against nuclear energy to this day. Positive public perception of the US in Germany was largely an aftereffect of the post-war era and a response to fear of possible Soviet revanchism for German war crimes.

Heck, the Marshall Plan was publicly perceived as an act of charity when in reality it was a loans program strongly tied to anti-communism (again exceeding mere "anti Soviet influence" but targeting leftist politics in general) and had the goal of building up Western Europe and West Germany as a bulwark against the Soviet Union.

Say what you will about Americans, US organizations or even how the US government has changed since then, but the Cold War era US government was scary and much like the Soviet Union felt more like a force of nature than a diplomatic ally you could reason with.

I can definitely recommend the music, very atmospheric, very alien.