
Lost Advanced Civilizations - headalgorithm
https://www.overcomingbias.com/2020/08/lost-advanced-civilizations.html
======
benbreen
From the OP: _" On the other hand, we often hear reports of people uncovering
old things that others had confidently predicted would never be found. Which
makes many suspect widespread overconfidence in claims about what we know
can’t be there, because if so we would have seen them already."_

Hanson here appears to be backing up his claim with three hyperlinks. One
thing that troubles me about rationalist-affiliated writing is that it tends
to rest on what _looks_ , at first glance, like a decent evidence base, but
this evidence often breaks down under a little scrutiny. For example:

• Hanson's first link is to a recent _National Geographic_ article that
summarizes an archaeology finding from Bronze Age China. The summary is, IMO,
misleading in one key respect. It calls the find "astonishing" because "parts"
of the site "date back 4,300 years, nearly 2,000 years before the oldest
section of the Great Wall—and 500 years before Chinese civilization took root
on the Central Plains." The Great Wall reference is a non sequitur: it's a bit
like saying that a find from the Old Kingdom of Egypt is astonishing because
it dates back to two thousand years before the building of a Roman aqueduct.
There's no real connection, and it's not at all news that agricultural
civilizations existed in China circa 2300 BCE. Whether we want to call these
societies "Chinese civilization" or not is debatable. But this finding, while
really interesting and cool, is very different from what Hanson seems to be
reading it as -- which is to say, as evidence for the belief that future
discoveries might yield signs of "advanced civilizations" which _far predate_
the Bronze Age as it's currently imagined. After all, in 2300 BCE, written
records and urbanized societies already existed in a fairly large swathe of
Eurasia.

• His second link is simply to the Wikipedia page for Göbekli Tepe. Which is a
totally fascinating site, I agree. It certainly does have unique features,
such as the megalithic carvings. But again, it is _not_ evidence of an
entirely unknown "advanced" civilization; instead, the people who built
Göbekli Tepe clearly fit into the existing archaeological record relating to
the Neolithic Near East. We've known for some time that early agricultural
societies were emerging in the fertile crescent around the same time as this
site. What's fascinating about this site is that it appears to predate
agriculture in the region. However, it _is_ thought to fit into a transitional
stage ("Recent DNA analysis of modern domesticated wheat compared with wild
wheat has shown that its DNA is closest in sequence to wild wheat found on
Karaca Dağ 30 km [20 mi] away from the site, suggesting that this is where
modern wheat was first domesticated"). So again, IMO this has nothing to do
with his claim about "lost" civilizations which don't fit into our existing
chronology.

• The final link is to a _Nature_ write-up from two years ago relating to a
contested claim about when humans arrived in the Americas. Again, this has
nothing to do with evidence for an "advanced civilization" that has previously
not been discovered.

All three of these links reference really interesting and important work which
I very much hope continues to be funded and elaborated on. I'm convinced that
there are incredible mysteries in store in the future, especially in the field
of underwater archaeology. Yet to my reading, none of these reports relate to
phenomena that scholars "confidently predicted would never be found." Any
archaeologist or historian with a sense of humility will gladly admit that
there are a huge number of unknowns in the historical record. None of this can
be leveraged as a basis for the existence of "lost advanced civilizations" (by
which he appears to mean agricultural or otherwise technologically-advanced
civilization that far predate the Agricultural Revolution as its currently
understood, and which were forgotten after some kind of hypothetical period of
decline).

For that, you need what Hanson waves away: actual archaeological or historical
evidence.

~~~
andrewmutz
But by your own quote, he is not presenting these as evidence of advanced
civilizations. He is presenting these examples as evidence of "old things that
others had confidently predicted would never be found".

~~~
benbreen
Right, and I'm arguing that none of these cited articles are valid evidence
for that claim. Leaving aside the fact that his vague wording gives him
enormous wiggle room, i.e. "others" could refer to anything from professional
archaeologists to the _Ancient Aliens_ guy and "old things" could mean almost
anything.

~~~
prox
This is why a I think it is a bad article. He first proposes some far-outlier
theories, which need extraordinary proof as he acknowledges himself. He does
not give it in the article which propels his theory in the realm of fantasy.
His article would be way more honest if he would describe it as pure
speculation, instead of shoehorning all kinds of finds or theories into his
flight of fancy.

I mean it is a fantastical idea, and if we ever find a laptop from 10000bc I
would be stunned, or if we find marsian burial chambers, but the probability
just isn’t very high on what we observed sofar.

That isn’t to say a lot is lost to history, which skews our interpretation,
especially prehistorical, but that would warrant a different kind of article.

~~~
LargoLasskhyfv
You mean like [https://www.theatlantic.com/science/archive/2018/04/are-
we-e...](https://www.theatlantic.com/science/archive/2018/04/are-we-earths-
only-civilization/557180/) which links to
[https://arxiv.org/abs/1804.03748](https://arxiv.org/abs/1804.03748) ?

------
tshaddox
> Here the key question here is: what sort of things should you expect to have
> already seen, if they were really there? On the one hand, we clearly have
> seen enough to safely conclude that there aren’t large dinosaurs roaming the
> streets in our major city centers. On the other hand, we often hear reports
> of people uncovering old things that others had confidently predicted would
> never be found. Which makes many suspect widespread overconfidence in claims
> about what we know can’t be there, because if so we would have seen them
> already.

This wording is very reminiscent of a lot of writing from conspiracy
theorists. It starts with a very plausible claim that experts are sometimes
overconfident in a mainstream belief about topic X, but then immediately leaps
to the conclusion that we can therefore make up any claim whatsoever about
topic X and it ought to be treated just as seriously as mainstream beliefs
held by experts.

You see this all the time in government/political conspiracy theories. Yes, we
have in the past uncovered real substantial government conspiracies and
attempted cover-ups. But that doesn't mean that any claim whatsoever about a
government conspiracy is true or should be treated "with the same priors" as
any other claim. Likewise, the fact that some experts have been wrong about
what artifacts they expected to find in a certain archaeological dig does not
mean that all claims about human history should be treated with the same level
of seriousness. The fact that sometimes evidence is hidden (either
deliberately, or due to lack of resources, or due to misguided research, etc.)
does not support any arbitrary claim made without evidence of its own.

~~~
rsa25519
> This wording is very reminiscent of a lot of writing from conspiracy
> theorists

I think this dismisses the article as a whole a bit too quickly.

> The fact that sometimes evidence is hidden... does not support any arbitrary
> claim made without evidence of its own.

Agreed. I didn't interpret the author as trying to imply this. I think the
author was trying more to fight an instantaneous "no you're definitely wrong"
than to convince the reader "yes this author's claim is correct."

~~~
prox
I think it doesn’t. A lot of conspiracy theorists use a technique where they
start with something that is true, some facts A and B, and then C is
controversial. You let your guard down with A and B, and are more susceptible
with C.

He is honest with the extraordinary proof he needs, but his article never much
strays from pure speculation. It’s a nice flight of fancy.

A lot is lost to history, no doubt, which skews our understanding greatly,
especially prehistorical. But that is Dozens of steps away from finding a
laptop from 10000bc or marsial burial chambers and having your advanced
civilization theory stick.

The article felt like shoehorning theories / finds to make them stick in his
view.

~~~
koheripbal
...but I think the author is being honest about it being speculation. If you
read the article to the end, his conclusion is that outlandish speculative
claims should be incentivized to be proven through a betting market that can
reward proof proportionately.

ie. Having the mainstream put their money where their mouth is.

I don't see an issue with that. He isn't actually claiming that prior
civilizations exist - simply that it's _plausible_ that they did (depending
upon what you interpret as "advanced").

------
antognini
> Some supporting evidence comes in the form of writings from the earliest
> authors we can find, who explicitly claim that they descended from more
> advanced prior civilizations, who fell due to big cataclysms. This story is
> actually quite common.

It's hard to know to what extent Golden Age and Age of Heroes myths were
rooted in or developed out of real events, but by the time many of these myths
were written down civilization _really had_ collapsed across the Near East and
Mediterranean some 800 years earlier [1]. The Late Bronze Age collapse was in
many ways more catastrophic than the fall of the Roman Empire 1500 years
later.

But the civilizations that fell during this time period were civilizations
from which we have ample evidence like the Mycenaeans (who may have been the
inspiration for Greek Golden Age myths), not some mysterious civilization that
had invented Segway scooters tens of thousands of years in the past.

[1]:
[https://en.wikipedia.org/wiki/Late_Bronze_Age_collapse](https://en.wikipedia.org/wiki/Late_Bronze_Age_collapse)

~~~
davedx
I still wonder what inspired Plato's Atlantis.

~~~
simiones
Do you also wonder what inspired J K Rowling's Harry Potter? Or Ayn Rand's
Atlas Shrugged?

We are quite capable of pure fiction with symbolic inspirations, there is no
need to suspect "a kernel of truth" behind any speculation.

~~~
davedx
Many classical mythologies had basis in reality: the Iliad is a great example.
Why are we so sure Atlantis is a myth (or allegory) while the stories of the
Bible are based on real events? It’s just not that simple.

~~~
simiones
That's very simple: because Atlantis was presented as an allegory by its
inventor, while most of the Bible was intended as history. Wondering where the
real Atlantis was makes about as much sense as asking who was the historical
prodigal son...

------
subsubzero
I don't know about lost civilizations, but ancient Rome was using concrete
technology unknown to medieval builders[1]. Somewhere along the line, this
super concrete recipe was lost. I find this really fascinating and some
believe that ancient Egypt also created its pyramids using man-made stone
instead of quarried stone:

> His most remarkable claim is that the pyramids were built using re-
> agglomerated stone, a sort of geopolymer limestone concrete, rather than
> blocks of natural stone.

[1] - [https://www.wired.com/2009/10/super-concrete-in-the-us-
milit...](https://www.wired.com/2009/10/super-concrete-in-the-us-military-
iran-and-the-pyramids/)

~~~
mountainboy
My understanding is that Roman concrete recipe/technique is considered
uneconomical for most uses today because it uses very little water and must be
mixed onsite and packed into place, which makes it much stronger even without
rebar. But that doesn't work so well for mixing in a truck and driving to job-
site, so modern industry prefers a much wetter mix even though it means our
structures crumble in decades rather than millenia.

Where the similar recipe/technique has been applied is in the construction of
some large dams, where they call it roller compacted concrete.

see romanconcrete.com

~~~
azepoi
did anyone made tensile tests on a roman concrete specimen? Rebar is wildly
used because reinforced concrete is not only used in compression but in beams,
slabs ... and could be avoided in arched structures. Arches and domes can last
a lost longuer but limit choices in what can be built. Roman concrete should
be compared to modern concrete without rebar or this is comparing apples to
oranges.

~~~
WJW
It's just a different tradeoff. We could absolutely make "Roman" concrete that
lasts millennia, but it has a much lower strength than modern concrete so you
can't make something like a harbor quay out of it. That said, "lasting a
thousand years" is not as useful as it sounds, 99+++% of buildings will need
to be demolished before that time anyway.

~~~
pharke
> you can't make something like a harbor quay out of it

Are you sure about that? The Romans built a lot of harbours. We don't really
have any data on the compressive or tensile strength of Roman concrete so it's
hard to say for sure.

~~~
WJW
You can't make a _modern_ harbor quay out of it, one that is strong enough for
the super large container cranes. The main problem is of survivorship bias:
all the flimsy Roman harbors have disappeared so yes, only the most sturdily
constructed ones remain. They would still not last under the "modern" load of
40+ ton vehicles.

------
PaulDavisThe1st
>You see Mars is, a priori, just as likely a place for life to start as Earth.

Asserted without evidence, and considerable waving of hands detected.

~~~
danudey
"a priori" means "from theoretical deduction rather than evidence or
experience", so yes, that's entirely the point of that sentence.

What the author is saying is "theoretically, life could have started on Mars
just as easily as it did here".

~~~
PaulDavisThe1st
The theories we have about how life started on Earth tend to disfavor Mars as
a similar starting point, based on what we currently know about Mars.

I think the author was trying to say "I mean, look, Earth and Mars are not
that different, and even though we don't have any current evidence for the
appropriate chemical conditions on Mars, I don't see why it couldn't have been
where life started instead of Earth, because ... well, just because they're
sort of similar, kind of. Oh, and next to each other."

~~~
brudgers
_based on what we currently know_

In two hundred years, conclusions drawn from what we currently know will be as
out of date as conclusions from two hundred years ago are today. Or to put it
another way, things known to the best of our knowledge are both as good as we
can do and probably wrong because one of the things we know is that
historically most of what people know at any given time turns out to be wrong
at any given time.

~~~
PaulDavisThe1st
Absolutely correct. But this article was written _now_ , and makes a claim
that is totally unsupported by anything we know _now_.

I'm entirely down for our descendants in 200 years laughing at our scientific
parochiality, just like we often get to do at our double-century antecedents.
But that doesn't justify writing _right now_ that Mars and Earth have a priori
likelihoods of being the origin of life in the solar system.

------
SpicyLemonZest
Prizes for finding specific things in specific years don't reflect the
structure of how ancient archaeology actually works. Picking domesticated
horses as a hopefully representative example:

* The earliest clear, irrefutable example of domesticated horses - horses and chariots put into a grave together - is from 2000 BCE.

* Most sources are confident horses were domesticated by 3000 BCE.

* There's archaeological evidence for domestication as early as 3500 or 4000 BCE.

* The closest known wild relative of the domestic horse diverged genetically tens of thousands of years ago. But it's believed that this was a natural event, and _Equus ferus caballus_ was wild for some time before humans domesticated it and drove the wild stock extinct.

If there's a prize for showing horses were domesticated west of the Caspian
see before 3000 BCE, is it awarded or not? I don't know and I don't see any
great way to decide.

~~~
tuatoru
Off topic, but on the topic of your specific example: there's a nice book
called _The Horse, The Wheel, and Language_ [1] about this.

Great if you want to learn about analysing fossil horse teeth for bridle bit
wear. Oh, and about Indo-European languages.

Edit: By 'you" I didn't mean parent specifically but "the reader".

[1]
[https://en.wikipedia.org/wiki/The_Horse,_the_Wheel,_and_Lang...](https://en.wikipedia.org/wiki/The_Horse,_the_Wheel,_and_Language)

~~~
LargoLasskhyfv
Sigh...

another piece for my Tsundoku-stack.

;-)

------
hprotagonist
[https://arxiv.org/abs/1804.03748](https://arxiv.org/abs/1804.03748)

 _If an industrial civilization had existed on Earth many millions of years
prior to our own era, what traces would it have left and would they be
detectable today? We summarize the likely geological fingerprint of the
Anthropocene, and demonstrate that while clear, it will not differ greatly in
many respects from other known events in the geological record. We then
propose tests that could plausibly distinguish an industrial cause from an
otherwise naturally occurring climate event._

~~~
cryptonector
If such a civilization was confined to the shores of what is now the black
sea, but which before the current interglacial was a fresh water lake whose
level was much lower than today's, then no, we wouldn't be able to detect it
casually -- we'd have to work real hard to find it. For civilizations confined
to open sea shores the situation is much less dramatic because the sea level
rise there was less than at the black sea, but still, there could be some that
are 30 meters under water (accessible) but completely covered in sediment (so
inaccessible).

Seems... unlikely to me. Plausible, yes, but unlikely. In particular any pre-
interglacial civilization would have had to develop during the preceding
glacial period, not before it because that would take it back 100Ky, which is
too much to be believable given what we know so far about our species'
evolution (though anything from more than 100Kya would be hard to find
indeed). And evidence of it would have to have been destroyed by sea level
rise during the interglacial, but why would the civilization itself be
destroyed by the interglacial?

~~~
BuckRogers
I think you’re correct. The story on our species is known to degree that it’s
unreasonable that an advanced agricultural civilization existed. I think it’s
more likely that far further back, a dinosaur species achieved a more advanced
state than we think possible today. Not quite agricultural due to a lack of
tool use, but as far as you can go without the opposable thumb. Advanced
social structures and nomadic. It’s pointless speculation, but I do think it’s
more likely given the timespan available.

------
gojomo
I fear the market Hanson proposes would incentivize skilled hoaxes as much or
more than authentic discoveries.

~~~
notahacker
This. (and you could probably reply to 90% of Hanson's 'you can solve problem
X with a prediction market' posts with essentially the same argument)

It's not like people with understanding of archaeology aren't already highly
incentivised - financially and otherwise - to discover evidence of ancient
civilizations if it's actually there. Archaeological frauds exist even now,
and even where there is no fraud there are enough disputes in dating and what
actually constitutes advanced civilization to guarantee a prediction market in
archaeological discovery is going to have a massive oracle problem...

------
Animats
If there had ever, in the last few million years, been mining on a scale
comparable to what goes on today, we'd notice. Some natural resources would be
used up. The oldest mountain range on earth is over 3 billion years old. It's
in South Africa. It's being mined. It's not mined out.

If this planet ever had an industrial civilization, every once in a while we'd
find something made of gold or stainless steel or ceramic. Not happening.

~~~
koheripbal
It sort of depends on what you mean by "advanced". A civilization that simply
had pottery 50K years ago, would be considered "advanced" and a major major
breakthrough.

If it did only happen on an island which is today submerged, then probably we
will never discover it without major investments to look (which are poor
investments since the probability is low).

...and hence, the author's main insight is that low-probability discoveries
should be incentivized by prediction markets such that those who believe in
the status quo can safely buy their positions - and that anyone who can upend
the status quo is richly rewarded.

I think that, conceptually, has merit.

------
LargoLasskhyfv
Imagine they were so advanced that they had the ability to 3D-print really
everything in high volumes from the quantum level up. From large scale
building materials analog to our concrete and steel to metamaterials, isomers,
Nano/Synbio, whatever.

What to do about the rat-race/treadmill?

Of course artificial scarcity by ubiquitous DRM embedded at quantum-level in
absolutely everything!

Which after a while of missed payments self-destroys into ecologically safe
mono-fractions.

Ashes to ashes, dust to dust, gone with the wind...

edit: or instead of missed payment a simple countdown/timeout, because why
have old things at all?

~~~
filoeleven
Why even bother with quantum DRM? A sufficiently advanced organization of
matter is indistinguishable from noise if you lack the capability to decode
it. See an encrypted file or a butterfly chrysalis: it all looks like noise to
us, but something emerges with the right key.

What if there was no hierarchy in this proposed civilization? Or what if they
developed the means to encode civilization-wide access rights to every object
they handled by saying “the nth crystalline molecule from the top (read right-
to-left) has your signature flaw embedded in it?”

We have no way of detecting that with our current tech level, and even if we
could trivially detect the crystalline flaws it doesn’t mean we’d see or
comprehend the scheme they employed. Working with a tech model that we
understand (well, some of us, not including me), if you handed a hard drive to
a Roman emperor and told them what it held, they wouldn’t be able to do
anything with it or even examine it non-destructively even if they put the
whole of the empire to the task.

Ain’t trying to say that it existed. I do like the remark in one of the
Culture series that says technology is more like a rock face than a line:
different sequences of discoveries lie along the path that a particular
civilization travels. There’s lots of room for surprise, whether discussing
ancient, contemporary, or future civilizations.

------
keenmaster
Here are some problems with prediction markets that Tyler Cowen enumerated in
2006:
[https://marginalrevolution.com/marginalrevolution/2006/03/wh...](https://marginalrevolution.com/marginalrevolution/2006/03/why_dont_busine.html)

That was before machine learning became a thing. I wonder if ML can detect
patterns in voting behavior to downrank/uprank certain predictions to get
closer to the likely truth. Obviously the more liquid the market is the
better.

Edit: Someone downvoted me but I'm not sure they're aware that Robin Hanson
(the author) is a big advocate of prediction markets, which are also a central
feature of the original post. I think highlighting the issues with prediction
markets and speculating about a solution is germane to this discussion,
especially since prediction markets can be very valuable for society.

~~~
pjscott
Those look very specific to using employee-only prediction markets to guide
decision-making within a single company. Which objections, if any, do you
think apply to Hanson's proposal for tradable archaeology prize obligations?

~~~
keenmaster
Abstracting away from the corporation-specific concerns, there is an incentive
problem. Vested interests can seek to lower the usefulness of the market's
"price as a signal" by placing large diversionary bets. Granted, this is
relatively less likely to be a problem in the archaeology space. What
definitely may be an issue is lower liquidity.

Every time I see a post like this I think "where are all the prediction
markets?" Regulations are one reason, but that's far from the only reason. If
information/prediction markets are enhanced using new technology, regulators
will begin to respect them more and allow for widespread use in non-academic
contexts.

------
ncmncm
If there are remains of a civilization from, say, 15000 years ago, very few
are looking for it. In the Americas it is very hard to get permission even to
continue digging below the Clovis layer.

Furthermore, it is just as likely to be under 60+ ft of water. We don't need
to find the water for a worldwide flood -- it's all still there, since the ice
melted, right there in the sea. Literally tens (or hundreds, going back a
little farther) of thousands of square miles of what was very recently dry
land is now underwater, more than enough room for some regional empires.

People who lived on those square miles had to pick up and move uphill, and
leave their ancestral homes behind. (That, as anyway, is pure fact.)
Australians have oral history of the conflicts that move caused, because other
people already lived uphill.

It's not an extraordinary claim. Nothing makes it _prima facie_ unlikely. It
just takes looking for evidence in places no one has chosen to look, yet.

We do know that a sophisticated civilization (tree-)farmed the whole Amazon
basin, right up until they were wiped out by smallpox 500 years ago. LIDAR
reveals many, many miles of huge earthworks. No one suspected, only a few
years ago. We still know hardly anything about them. So, no, lost
civilizations are not an extraordinary claim.

Lack of lost civilizations, where they ought to have arisen, needs
explanation.

~~~
simiones
> So, no, lost civilizations are not an extraordinary claim.

> Lack of lost civilizations, where they ought to have arisen, needs
> explanation.

Well, lost cultures as advanced as, say, the builders of the Egyptian
pyramids, but significantly older, is still an extraordinary claim.

In fact, claims of any kind of civilization existing require some kind of
proof - it makes no sense to say "the British isles can sustain a thriving
civilization today, so we should assume that there was a civilization present
there 100k years ago, unless we have some evidence to the contrary (or at
least wonder why no civilization flourished there some at that time)".

~~~
ncmncm
No, it is an ordinary claim, requiring ordinary evidence.

The Egyptians had no magic powers. They had population, surplus food, and
regular human ingenuity. Anywhere that happens, civilization arises, like
desert wildflowers after a rain. If the wildflowers don't bloom, that requires
explanation.

You do understand that we need evidence for everything, right?

But bending over backward to try to discount the evidence we have because it
must be not just regular, workaday evidence, but _extraordinary_ evidence, is
not science. It is, instead, hardscrabble turf defense, and nothing to brag
about.

------
peterwwillis
So, assume this is all true. We came from Mars and advanced civilizations came
and went, completely undetected. Who the fuck cares? Isn't not like we can dig
up their ancient technology and use it now, can we? It's a fantasy for people
who don't have the imagination to believe in dieties. Super-advanced-yet-dead
civilizations are a cheap imitation of dead Gods.

------
WalterBright
The scifi novel "The Hab Theory" by Eckert goes into some interesting debate
about whether there were unknown previous advanced civilizations or not. It
sounds _almost_ plausible, but not quite.

"Inherit the Stars" by Hogan is another interesting take on it.

~~~
LargoLasskhyfv
There is a fringe theory similar to HAB (thx for mentioning it btw., didn't
know that) wherein the earth tilts by about 90 degrees for a few days and then
back, but the mechanism is different. Supposedly caused by changing magnetism
and structure/viscosity of some larger parts of earths molten layers, changing
the center of gravity for a while, and so on.

------
motohagiography
Clearly the author has not eaten boxes of those newly legalized brownies and
binge watched seasons 1 through 15 of "Ancient Aliens." If he had, he would
know that "ancient astronaut theorists, would say yes."

It's entertaining, but what subtle improvement has he made on the work of
eminent theorist Giorgio A. Tsoukalos?

~~~
LargoLasskhyfv
No binge watching of bad hair required. 20 minutes suffice. (even less,
because skippable/fast-forwardable)

 _The Unusual Earth Orbit Circling Above Our Ancient Past | Roger G.
Gilbertson | TEDxColoradoSprings_

[1]
[https://www.youtube.com/watch?v=_HytJn6uaRk](https://www.youtube.com/watch?v=_HytJn6uaRk)

Maybe another (less than if fast forwarded) 30 minutes for

 _Proof a Mysterious Lost Ancient GLOBAL Civilization Spanned Virtually the
Entire Planet…_ from:

[2]
[https://www.youtube.com/watch?v=BTd1fRCAvR4](https://www.youtube.com/watch?v=BTd1fRCAvR4)

------
mellosouls
A reminder of the rather more ancient civilisations imagined in the Silurian
Hypothesis thought experiment of a couple of years ago:

[https://www.wikipedia.org/wiki/Silurian_hypothesis](https://www.wikipedia.org/wiki/Silurian_hypothesis)

------
javert
Prediction markets are not legal in the U.S.

(There are some with low limits, like $1000 per position or $5k per person---I
don't remember exactly---but I do not consider those to be "real" prediction
markets.)

------
pmlnr
RE not found evidence: I always imagine what would have happened if we were to
start with biology based tech. A few centruries, and poof, nothing left. Now,
put that into a million years perspective...

~~~
Udo
That depends on what you mean by biology-based tech, afterall, we're also a
civilization deeply rooted in biology-based tech.

It's not necessarily the case that all organic materials are ephemeral over
these timespans. Assuming that a tool-using civilization would have needs
covering a wide range of material properties, including high corrosion
resistance, there is no reason why even biologically-grown building materials
would automatically be less durable than, say, concrete. Not to mention the
tools and trinkets of everyday life. The assumption is that a large population
always has a large footprint regarding the traces it leaves behind, even if
that footprint is very different from ours. We found this to be true in
fossils that have been left behind even by exceptionally fragile creatures.

Once we're talking advanced biology-based tech, this becomes even more
pronounced. Outright genetic engineering in Earth's past would be bound to
leave very curious traces in lifeforms that are around today. In fact, if I
wanted to leave a message behind for a hypothetical civilization located on
this planet a million years into the future, leaving it in DNA would be one of
the very few viable choices.

I would posit that even DRMed biotech designed to turn every single piece of a
civilization into mud once the license runs out would leave behind very
detectable traces in the form of strange geological deposits and individual
artifacts that survived against all odds.

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biolurker1
The last paragraph is an example.of innovation that can only be achieved with
blockchain projects like Augur prediction markets and ettlements. Cool stuff

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jungletime
Archaeologists have discovered a 7,000-year-old well built by Neolithic
farmers in what is now the Czech Republic.

[https://www.cbsnews.com/news/ancient-well-oldest-wooden-
stru...](https://www.cbsnews.com/news/ancient-well-oldest-wooden-structure-
ever-discovered-archaeologists-czech-republic/)

~~~
rnet85
7000 years is pretty modern, it’s almost 3k years after agriculture started
being adopted in multiple regions. There are older artifacts than that,
intelligent humans have been on the planet for a long time.

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lukev
I was perturbed by the offhand way he linked to a climate-change denialist
website (as part of his assertion that "before 10k temperatures changed a lot
more").

I don't think you get to call yourself a rationalist if you ignore the
overwhelming scientific consensus in favor of a blog run by right-wingers.

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richardfey
How does this kind of garbage reach the top of HN?

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knolax
It seems that dilettante intellectuals have rebranded themselves as
"rationalists". Why is it that their blog posts are always high school book
report level quality.

