Civilization: How to make it happen under the sea.

[Radar]

So the name of the game is to explore the possibility of sea creatures to build a technological civilization. In order not to get hung up on specific technological achievements (fire, metallurgy, farming, etc.) I think it would be productive to first focus on the impact those discoveries had on humanity, how vital it actually was and then ponder if something else could have the same or similar effect. Or in other words recognise and generalize the stepping stones in our own advancement.

Many sentient creatures are curious, intelligent and can learn quite a lot of complicated ideas and manual tricks. In order to have any advancement, you have to first have means of preserving knowledge and giving it to the next generation. So a first must have:

1. Communication and information retention through generations.
This also indicates that we should expect civilization to happen only for social species. Lone predators obviously have no use for sophisticated communication.


As long as everyone is busy surviving, new discoveries are random and as such very rare. What really jumpstarted our progress was farming: it was the first moment in history, when not everyone had to focus on finding food. With this there was room for some people to focus on other stuff like making better tools or looking up at the night sky on a warm summer evening and noticing that some of the stars seem to move. So another point on my list:

2. Efficient food production.


To get some nice tools one needs something to make them from. For us it were stones, bones, leather and later various metals, clay, glass and so on. So one way or the other you need:

3. Workable materials.
(for making tools, structures and whatever else)


As became evident to me, these are less singular events and more directions in which civilization was improving using various particular technologies, so we can consider some particular steps in each category that were huge game changers for us as well. So I am way past the point, when I should be sound asleep, so excuse me for any typos and logical errors and feel free to adopt, adapt and improve.

[Tvtyrant]

I would probably look at coral reefs and something like the Cuddle Fish. They are intelligent, they have the reef for structures and materials, and they could easily farm shrimp, fish or the coral itself. A cuddlefish with a knife or spear could deal with most of the reef predators, and they are social animals so they can pass on traits.

[Flyingbooks42]

I recently wrote a story which included an oceanic civilization. Although they did not come close to each other very frequently in their early development, they were able to communicate over long distances (like whales). Although they reproduced by letting their egg/sperm equivalents float around in the water, newborns gave off strong pheromones that could trigger an adult's parental hormones from kilometers away, so they were able to pass on information and techniques from generation to generation. There were edible underwater plants and fishlike creatures that could be farmed for food and stiffer plants that could be shaped into tools as they grew. The larger variants of these plants could be formed into buildings, though they were only made relatively recently in the species' development in order to store equipment that was sensitive to currents and small creatures.

[-D-]

Here are my thoughts on it. I think Octopi could work, but they would need to be slightly different than regular Octopi.

A) They probably would have to partially care for their young, i.e. they don't die post-coitus.
B) Semi consequence of A) they would have to be sociable. Sociability would help them grow bigger brains and communicate better.

I'd probably use this as a primer: https://worldbuilding.stackexchange....ate-technology

So you're going to abandon the oceans to go crawl up one particular river to find the one species that uses electricity as effectively a contact poison. So either you die in the fresh water, or you drag them to the ocean and they die from the salt water. Again, basic chemistry (tolerance for saline).

Also calcium carbonate is limestone, which dissolves in water (hence the sinkholes slowly eating Florida). Most bicarbonates are also water soluble at low temperatures, and many others as temperature rise. If you're going to build with those, you need to invent cooling systems first.

First off. Pretty sure that there is more than one electric generating organism. If they can't find eel, they could tame some other seaborne electric organism. And there are plenty of those in the sea.

For sanity sake, I won't consider Holocene effect on evolution of Octopi intelligence. But given different form of bicarbonates, they'll use the one that don't melt in sea water.

[Keltest]

Here are my thoughts on it. I think Octopi could work, but they would need to be slightly different than regular Octopi.

A) They probably would have to partially care for their young, i.e. they don't die post-coitus.
B) Semi consequence of A) they would have to be sociable. Sociability would help them grow bigger brains and communicate better.

I'd probably use this as a primer: https://worldbuilding.stackexchange....ate-technology



First off. Pretty sure that there is more than one electric generating organism. If they can't find eel, they could tame some other seaborne electric organism. And there are plenty of those in the sea.

For sanity sake, I won't consider Holocene effect on evolution of Octopi intelligence. But given different form of bicarbonates, they'll use the one that don't melt in sea water.

How would they obtain and shape these bicarbonates? Bearing in mind that they only have stone/bone tools, as this is intended to be the next stage in tech development.

Also, having some references to what specific material you have in mind would be nice. It's rather difficult to address any claims or arguments about a material that we don't know the name or properties of.

[Max_Killjoy]

I stand by everything I said in the other thread.

The claim was made that it was simply a quirk of fate that the octopus didn't become the dominant technological species on Earth, and yet absolutely no actual working process by which the hypothetical octopeople would have gotten past basic stone age tools while not becoming terrestrial first has been put forth by this time -- every idea put forth has so far been farcical whimsy and/or rested on a series of unfounded "but they could have" without being able to actually explain how they could have.

And when confronted with the fact that they're not actually backing their claim, the supports of this octopeople hypothesis have fallen back on a "you just lack imagination" ad hom argument.

Until such time as they offer something solid and detailed and workable, I will continue to unapologetically consider this concept of an aquatic species developing space travel without first becoming terrestrial so much fanciful bunkus.

How would they obtain and shape these bicarbonates? Bearing in mind that they only have stone/bone tools, as this is intended to be the next stage in tech development.

Also, having some references to what specific material you have in mind would be nice. It's rather difficult to address any claims or arguments about a material that we don't know the name or properties of.

Yes, I would very much like the actual name of this specific building material, and how it would be discovered and obtained and worked, rather than the now-typical "but they'd find one that would work" argument we're getting.


"But electric eels!" is one of the things we've seen repeatedly, as a way to refine metal via electricity... never mind that you'd need about 50000 electric eels, which tire in under an hour, to run a single arc furnace... and that you'd be doing it underwater... and that you'd need some way to refine metal and turn it into wire first, before using electrical refining tech... there's a reason why using fire to refine metal is 1000s of years old, and using electricity to refine metal is what, 200 years old or less?

[-D-]

How would they obtain and shape these bicarbonates? Bearing in mind that they only have stone/bone tools, as this is intended to be the next stage in tech development.

Also, having some references to what specific material you have in mind would be nice. It's rather difficult to address any claims or arguments about a material that we don't know the name or properties of.

Well, think about how primitive humans went about it. They killed creatures or foraged their skins, bones, etc. as tools.

I had in mind seashells. So whatever those are made from. Again, I'm not a biochemist, marine biologist, flow based physcist and historian, and can't tell you what exactly are you going to build next stage, as I said, I'm not that intimately familiar with materials that are available under the sea. If I had full list, I could probably give a better answer, but that's probably impossible because we don't know marine biology/chemistry that well.

The claim was made that it was simply a quirk of fate that the octopus didn't become the dominant technological species on Earth, and yet absolutely no actual working process by which the hypothetical octopeople would have gotten past basic stone age tools while not becoming terrestrial first has been put forth by this time -- every idea put forth has so far been farcical whimsy and/or rested on a series of unfounded "but they could have" without being able to actually explain how they could have.

Are you implying life isn't a quirk of fate? That it's somehow only possible for humans to evolve to this stage? What if a comet hit 100,000 years ago, extinguishing all primates? That there somehow wouldn't be an advanced intelligence out there?

Ok, do me a favor, prove that human ancestors could evolve into a space-faring civilization using your knowledge of marine biology and marine chemistry. Go. I'll wait.

And when confronted with the fact that they're not actually backing their claim, the supports of this octopeople hypothesis have fallen back on a "you just lack imagination" ad hom argument.

No. I explain how they could get stone tools (because they are already using them), but you ask about metal age? I claim they don't necessarily have the metal age at the same level and same stage as humans, and explain it's hard to tell, because the next stage could be wildly different for them compared to us.

Until such time as they offer something solid and detailed and workable, I will continue to unapologetically consider this concept of an aquatic species developing space travel without first becoming terrestrial so much fanciful bunkus.

The details you are asking about, are so minute that essentially answering them would be the equivalent of writing a hard Sci-Fi novel. Not to mention require consultation of several PhD.

[Keltest]

Well, think about how primitive humans went about it. They killed creatures or foraged their skins, bones, etc. as tools.

I had in mind seashells. So whatever those are made from. Again, I'm not a biochemist, marine biologist, flow based physcist and historian, and can't tell you what exactly are you going to build next stage, as I said, I'm not that intimately familiar with materials that are available under the sea. If I had full list, I could probably give a better answer, but that's probably impossible because we don't know marine biology/chemistry that well.


Are you implying life isn't a quirk of fate? That it's somehow only possible for humans to evolve to this stage? What if a comet hit 100,000 years ago, extinguishing all terrestrial life? That there somehow wouldn't be an advanced intelligence out there in the sea?

Ok, do me a favor, prove that human ancestors could evolve into a space-faring civilization using your knowledge of marine biology and marine chemistry. Go. I'll wait.


No. I explain how they could get stone tools (because they are already using them), but you ask about metal age? I claim they don't necessarily have the metal age at the same level and same stage as humans, and explain it's hard to tell, because the next stage could be wildly different for them compared to us.


The details you are asking about, are so minute that essentially answering them would be the equivalent of writing a hard Sci-Fi novel.

I hope youre aware that none of this is a particularly satisfying response to, well, any of the issues, at least in my eyes. If you cant even imagine what the next stage could potentially look like, if not with metals, why are you so certain that there even could be a next stage? Civilization is not the norm, if you removed humanity from Earth during the early stone age, theres no guarantee at all that we would have a similarly advanced civilization of, say, gorillas ruling the world by now. Yes, it may be a "quirk", but its also immensely complicated, requiring the culmination of a huge number of largely unrelated factors coming together to create the ideal environment for society to happen.

[Rogar Demonblud]

What they have available to them in the ocean is a lot of salt water. What resources there are are buried in a way that we can't reach them with our current technology without paying an exorbitant cost in money, effort and lives. With crude Paleolithic-era tools? Don't plan on it, especially since you'd need modern tech to find the deposits.

I take it back, there is another resource available. Methane clathrates could be burned for anything fire related. Two problems. First, getting to them means going down into the benthic deeps where the pressure will reduce you to paste from one heartbeat and the next--and then going even further down. Second, igniting the clathrates poses two threats by themselves: A} you warm up the clathrates enough that they melt and release methane, turning the water into acid (or eventually reaching the surface, Google "Big Fizz"), and B} the clathrates themselves burn and keep burning at an exponential rate, boiling the seas. A small pocket off the coast of Norway was touched off (we think by an underwater volcano), and the result was life on this planet was nearly reduced to the bacterial level. There's about 50,000 times that much just off the U.S. East Coast.

[-D-]

I hope youre aware that none of this is a particularly satisfying response to, well, any of the issues, at least in my eyes. If you cant even imagine what the next stage could potentially look like, if not with metals, why are you so certain that there even could be a next stage? Civilization is not the norm, if you removed humanity from Earth during the early stone age, theres no guarantee at all that we would have a similarly advanced civilization of, say, gorillas ruling the world by now. Yes, it may be a "quirk", but its also immensely complicated, requiring the culmination of a huge number of largely unrelated factors coming together to create the ideal environment for society to happen.

Because civilization isn't that unique IMO. Sure. Life is a quirk of chance but I don't think it's impossible for it to arise under wildly different conditions. Same with civilizations.

I can't imagine (within given constraints), because there isn't enough data to make an accurate guess. Is there an underwater creature that synthesizes a metal microstructure? I don't know. But it might. But then Max_Killjoy says it doesn't exist. And he might be right. Or wrong.

How are underwater deposits of minerals? Again we don't know, because we have enough of them on land. We don't need to dig them from the sea.

If I were to hazard a guess, they probably wouldn't mine so much as they would grow things that do that work for them.

What they have available to them in the ocean is a lot of salt water. What resources there are are buried in a way that we can't reach them with our current technology without paying an exorbitant cost in money, effort and lives. With crude Paleolithic-era tools? Don't plan on it, especially since you'd need modern tech to find the deposits.

You're talking a very human-centric viewpoint. We don't look for them the same reason we don't harvest stuff from asteroids. Not because there isn't stuff in space, but because it's dangerous to go to space to mine, and resource-intensive for our civilization.

Also not sure what clathrates was all about? Why would any sea organism need them?

[Max_Killjoy]

No. I explain how they could get stone tools (because they are already using them), but you ask about metal age? I claim they don't necessarily have the metal age at the same level and same stage as humans, and explain it's hard to tell, because the next stage could be wildly different for them compared to us.

The details are not minor, they're critical.

High-intelligence life, and civilization, are not quirks. They are the result of a multitude of compounding quirks that interweave with and build off each other.

So far, you've been insisting that in place of the quirks that lead to where we are now, most of which are simply impossible for an underwater species, there would be other quirks instead -- but you cannot tell us what those other quirks would be.

So far, you've been insisting that there would be a different next stage for the octopeople after their stone age -- but you cannot tell us what that next stage would be or how it would be achieved.

You're talking a very human-centric viewpoint.

No, he's taking a very fact-centric viewpoint, a very basic-science-centric viewpoint, and refusing to accept "there'd be something different we can't imagine because it's so different, but it would have happened because it would have happened" as a serious argument.

[Bohandas]

Let's take a look at things that would be easier underwater

1.) Tall buildings- Bouyancy would allow you to build much much taller than you could on the surface

2.) Transportation- less need for roads. The people swim, the vehicles for transporting things are effectively lighter due to bouyancy

[Keltest]

Because civilization isn't that unique IMO. Sure. Life is a quirk of chance but I don't think it's impossible for it to arise under wildly different conditions. Same with civilizations.

I can't imagine (within given constraints), because there isn't enough data to make an accurate guess. Is there an underwater creature that synthesizes a metal microstructure? I don't know. But it might. But then Max_Killjoy says it doesn't exist. And he might be right. Or wrong.

How are underwater deposits of minerals? Again we don't know, because we have enough of them on land. We don't need to dig them from the sea.

If I were to hazard a guess, they probably wouldn't mine so much as they would grow things that do that work for them.


You're talking a very human-centric viewpoint. We don't look for them the same reason we don't harvest stuff from asteroids. Not because there isn't stuff in space, but because it's dangerous to go to space to mine, and resource-intensive for our civilization.

Also not sure what clathrates was all about? Why would any sea organism need them?

No offense, but im not interested in your guesswork, i'm interested in what you can logically conclude from the data available. Right now what youre saying is quite similar to "if they had an underwater civilization, then they could have an underwater civilization" which is technically true, but not at all helpful. If we don't know about any underwater creatures that synthesize a metal microstructure, then assume there isn't one and that there wont be any contributing to octopus civilization. True, we don't know everything that goes on underwater, but we do know a great deal of it. As soon as you start inventing creatures that could just solve the problem at hand, you've defeated the point of the exercise, because now you've changed the environment enough that it doesn't match the one under examination.

[-D-]

The details are not minor, they're critical.

High-intelligence life, and civilization, are not quirks. They are the result of a multitude of compounding quirks that interweave with and build off each other.

Yes, and? Given enough time and space similar if not identical quirks will appear and result in similar structures.

So far, you've been insisting that in place of the quirks that lead to where we are now, most of which are simply impossible for an underwater species, there would be other quirks instead -- but you cannot tell us what those other quirks would be.

I never said underwater creatures would be in the same place we are now. That's your misrepresentation. I just said intelligent space-faring civilization. To the same extent, we count as one.

Second as I said, not enough data.

So far, you've been insisting that there would be a different next stage for the octopeople after their stone age -- but you cannot tell us what that next stage would be or how it would be achieved.

To reiterate, as I said, not enough data. I can speculate, but you'll retort that my speculation is not based on scientific fact.

No, he's taking a very fact-centric viewpoint, a very basic-science-centric viewpoint, and refusing to accept "there'd be something different we can't imagine because it's so different, but it would have happened because it would have happened" as a serious argument.

That it's too expensive to mine stuff underwater? Teh ****? Tomorrow we could have gold being too expensive to mine in the ground, because some country dumped too much space gold on the stock exchange. Prices depend on numerous factor, almost all of them are human-driven. One HUGE factor is that humans don't breathe in water. That drastically increases the price compared to A WATER BASED ORGANISM.

No offense, but im not interested in your guesswork, i'm interested in what you can logically conclude from the data available. Right now what youre saying is quite similar to "if they had an underwater civilization, then they could have an underwater civilization" which is technically true, but not at all helpful.

If they had an underwater civilization, they would use electricity. They would probably be much more inclined to manipulate living organisms. The nature of their senses would probably make them much better chemists than us. They would use ropes (made out of seaweed), and use buoyancy to support their habitats.

If we don't know about any underwater creatures that synthesize a metal microstructure, then assume there isn't one and that there wont be any contributing to octopus civilization.

Here lies the problem. For humans, it isn't interesting or necessary to evolve such creatures. For Octopi it would be very interesting. If you look carefully at our past, nothing like avocado or cucumber exists. Yet today it does. Because we wanted to eat it.

but we do know a great deal of it

We know very little about species living on land, what makes you think our knowledge of the greater oceanic landmass, we can't even directly explore is better?

[Max_Killjoy]

No offense, but im not interested in your guesswork, i'm interested in what you can logically conclude from the data available. Right now what youre saying is quite similar to "if they had an underwater civilization, then they could have an underwater civilization" which is technically true, but not at all helpful. If we don't know about any underwater creatures that synthesize a metal microstructure, then assume there isn't one and that there wont be any contributing to octopus civilization. True, we don't know everything that goes on underwater, but we do know a great deal of it. As soon as you start inventing creatures that could just solve the problem at hand, you've defeated the point of the exercise, because now you've changed the environment enough that it doesn't match the one under examination.

The 'argument' we're getting from them amounts to "assume the conditions are such that my conclusion would be true".

[-D-]

The 'argument' we're getting from them amounts to "assume the conditions are such that my conclusion would be true".

And from you the arguments is moving the goalpost and near impossible burden of proof. I already demonstrated they could easily reach stone age given a few tweaks (no post coital death and more sociability).

[halfeye]

Two things. Firstly, I don't believe sea life can get to space without colonising land.

Second, there are electric sea creatures:

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

[Keltest]

And from you the arguments is moving the goalpost and near impossible burden of proof. I already demonstrated they could easily reach stone age given a few tweaks (no post coital death and more sociability).

Reaching the stone age is a bit of a far cry from reaching space. Theres a rather significant gap between the two that need to be filled.

[Rogar Demonblud]

Let's take a look at things that would be easier underwater

1.) Tall buildings- Bouyancy would allow you to build much much taller than you could on the surface

2.) Transportation- less need for roads. The people swim, the vehicles for transporting things are effectively lighter due to bouyancy

Neither are true. Buoyancy only matters if you want the structure to float. What you need is a dome so it can deflect the oceanic currents without absorbing their energy. They will have roads, because that's just the best path between Points A & B. And even then the routes will be constrained by the currents because it takes too much energy to fight.

-D-, clathrates matter because they are the only source of usable energy available in the ocean where the energy budget is not negative. It's on the level of how we use hydrocarbons--no hydrocarbons, no technical revolution, because energy is the driving limitation. Electric eels need half again as much food as regular eels, just to get a contact range low-grade taser. To get enough energy out of them for industrial level use you're looking at stripping the oceans of food species.

Seriously, we've been studying oceanology since before we had recorded history, this isn't a blank slate. Mining metals at the bottom of the ocean means going through hundreds of meters of silt, where you have to have advanced metallurgy to build the tunnel you will use to keep it from collapsing. How do you get to those resources when you need to already have those resources to extract them? It's not a small problem, and one that crops up when people talk about coming back from whatever disaster is going to happen. Without modern technology, we cannot have modern life, and once we lose it, even if only for a short while, we're slowly going back towards the Stone Age.

[Max_Killjoy]

And from you the arguments is moving the goalpost and near impossible burden of proof. I already demonstrated they could easily reach stone age given a few tweaks (no post coital death and more sociability).

As explained in the other thread, the goalposts didn't move. At all. They're right were they always were. Asking you to fill in the holes (massive yawning chasms, really) in your theory, and explaining in detail where your assertions are flawed or incomplete, is not "moving the goalposts". For there to have been any moving of the goalposts, you'd have to have offered up some sort of evidence -- we can't demand more evidence than you've given when you haven't given any.

Maybe my mistake was using questions that gave you a chance to address the faults in your argument, instead of just making plain simple statements.

And no one has disputed that they could reach an underwater stone age of sorts. The problem is everything after that.

Neither are true. Buoyancy only matters if you want the structure to float. What you need is a dome so it can deflect the oceanic currents without absorbing their energy. They will have roads, because that's just the best path between Points A & B. And even then the routes will be constrained by the currents because it takes too much energy to fight.

-D-, clathrates matter because they are the only source of usable energy available in the ocean where the energy budget is not negative. It's on the level of how we use hydrocarbons--no hydrocarbons, no technical revolution, because energy is the driving limitation. Electric eels need half again as much food as regular eels, just to get a contact range low-grade taser. To get enough energy out of them for industrial level use you're looking at stripping the oceans of food species.

10s of 1000s of eels just for a single large factory using eelectricity as a power source.

Seriously, we've been studying oceanology since before we had recorded history, this isn't a blank slate. Mining metals at the bottom of the ocean means going through hundreds of meters of silt, where you have to have advanced metallurgy to build the tunnel you will use to keep it from collapsing. How do you get to those resources when you need to already have those resources to extract them? It's not a small problem, and one that crops up when people talk about coming back from whatever disaster is going to happen. Without modern technology, we cannot have modern life, and once we lose it, even if only for a short while, we're slowly going back towards the Stone Age.

Thus my comments on using electricity to refine metal... setting aside the problems of using electricity submerged in salt water... if you need electricity to refine metal, and you need metal to control electricity... where do you start?

[Rogar Demonblud]

I think -D- is right that they'd pretty much have to start with biotech of some kind. The problem being you can't get that far with selective breeding, and anything else requires a modern, very expensive lab.

[-D-]

-D-, clathrates matter because they are the only source of usable energy available in the ocean where the energy budget is not negative.

That's not true. There is one major source of energy you are definitely overlooking. Oceanic currents. You can extract energy from those using ropes and turbines, which you can use to create mechanical energy. It's not efficient, but it can work.

Another way to generate electric energy is to move saltwater over large quantities of rust. It's potentially useful if you can store that energy.

Seriously, we've been studying oceanology since before we had recorded history, this isn't a blank slate. Mining metals at the bottom of the ocean means going through hundreds of meters of silt,

I don't think that's entirely correct. Hydrothermal vents should be a rich source of metals and possibly within the survivable range for octopi. Also, occasional scattered meteorite should be usable as well (yes, some of the first metal tools were made from meteorites).

And no one has disputed that they could reach an underwater stone age of sorts. The problem is everything after that.

And my point is - If they can reach a stone age and have a way to accumulate knowledge, sooner or later they will be able to reach stars.

Each discovery potentially adds more tools to extract energy. Once you extract more energy, you open paths for different discoveries, which leads to more discoveries. One of these discoveries will eventually be space flight.

I think -D- is right that they'd pretty much have to start with biotech of some kind. The problem being you can't get that far with selective breeding, and anything else requires a modern, very expensive lab.

And this is why I say, you need to think from its perspective. Octopus can taste with his entire skin and smell from his every tentacle. He's already a swimming chemical lab.

[Keltest]

And my point is - If they can reach a stone age and have a way to accumulate knowledge, sooner or later they will be able to reach stars.

Each discovery adds to more tools to extract energy. Once you extract more energy, you open paths for different discoveries, which leads to more discoveries. One of these discoveries will eventually be space flight.

We understand your point, were just saying its incorrect. This isn't a video game, simply having stone age tech doesn't magically unlock the next step in a tech tree. It needs to actually be used to create that next step. Stone age people used fire to shape metals and otherwise refine materials that allowed them to do more things than they could before. Underwater, you lack the fire to give access to the next critical material level, so they either need an alternative, which you have not been able to identify to us among materials we know to actually exist, or they need an alternative way to access those refined materials.

[Bohandas]

Neither are true. Buoyancy only matters if you want the structure to float.

Bouyancy applies whether or not something is actually bouyant enough to float. Underwater everything is functionally lighter by an amount proportional to its volume (or, more technically, proportional to the amount of fluid displaced by its volume). You couldn't make a skyscraper out of wood on land because it wouldn't be able to support itsmown weight, but you might be able to underwater because much of its weight would be supported by the water itself. If you had a neutrally bouyant material you could theoretically build a structure that reached from the bottom to the top of the marianas trench without the weight of the structure being an issue

[Rogar Demonblud]

Hydrothermal vents produce sulphur in quantities dense enough to turn the surrounding water to hydrosulphuric acid. They do not release metals--those are dissolved in magma. Meteorites do hit the ocean, yes. At which point they shatter into dust, most of which stays in solution rather than precipitating to the bottom. What reaches the bottom sinks into the silt. Also, most of the ocean is pelagic/benthic, where octopi can't survive (they're a bottom dwelling species with relatively shallow pressure tolerances).

You need to already know about mechanical energy and have a use for it before harvesting it becomes worthwhile. When we did the first part is not recorded, but it took millennia before we started using it for grinding grain (using animals--wind and water came much later). And you don't have a way to store it until you crack several advances in chemistry and materials science, none of which take salt water well (again, something we've been trying to solve since Roman times).

As for running salt water over iron, yes, that works. Of course, you must first mine the hardrock to get the iron ore, smelt it to achieve the needed purity then hook it up to a power grid including copper wiring (so you need to mine cupric ore from the hardrock and smelt it, then roll it for wiring (the easiest step) before putting the whole thing together with those batteries mentioned above. Oh, and the wiring with corrode as well, and faster than the iron.

Really, we live on a planet that's mostly salt water. We've put a lot of energy into figuring out ways to go to the salt water without everything falling apart. All we've managed to do is make stuff fall apart slower.

[Max_Killjoy]

We understand your point, were just saying its incorrect. This isn't a video game, simply having stone age tech doesn't magically unlock the next step in a tech tree. It needs to actually be used to create that next step. Stone age people used fire to shape metals and otherwise refine materials that allowed them to do more things than they could before. Underwater, you lack the fire to give access to the next critical material level, so they either need an alternative, which you have not been able to identify to us among materials we know to actually exist, or they need an alternative way to access those refined materials.

Not only do they need fire, which they can't use, they need a way to keep the saltwater from interfering with the process both chemically and thermally... and they need access to ores which aren't accessible on the bottom of the ocean because they're buried under silt, encrusted with concretions, etc.

Living in the ocean is not just "like the atmosphere, but wetter", and not just a matter of breathing in water instead of in air. It's a largely different environment, with different challenges, some of which make advancing past the equivalent to the stone age orders of magnitude more difficult than it was above water.

(Using your post as a starting point, not disputing it.)

[Rogar Demonblud]

Bouyancy applies whether or not something is actually bouyant enough to float. Underwater everything is functionally lighter by an amount proportional to its volume (or, more technically, proportional to the amount of fluid displaced by its volume). You couldn't make a skyscraper out of wood on land because it wouldn't be able to support its own weight, but you might be able to underwater because much of its weight would be supported by the water itself. If you had a neutrally bouyant material you could theoretically build a structure that reached from the bottom to the top of the marianas trench without the weight of the structure being an issue

No you couldn't. Buoyancy rates change with every atmosphere of pressure, which changes about every ten meters. Something neutrally buoyant at the bottom of the Marianas Trench will collapse under its own weight before you get halfway up the trench. Something neutrally buoyant at, say, 500 meters below the surface will either tear itself loose from the bottom and shoot upwards with enough force to breach the surface like a Trident D5 or it will be crushed until it has the appropriate volume (see if you can find one of the videos where they do that with foam heads--scary, but interesting). And again, that says nothing about the ocean currents, most of which pack more kinetic energy per second than you would receive standing out in a Category 5 hurricane.

[Radar]

And from you the arguments is moving the goalpost and near impossible burden of proof. I already demonstrated they could easily reach stone age given a few tweaks (no post coital death and more sociability).

The problem is, you provide unproved statements claiming they are surely true. It is only natural and even constructive to examine those statements using the knowledge we have. The fact that there is not enough data to definitely prove or disprove the possibility of underwater space-faring civilization should not stop us from getting a better perspective with what we have and we have quite a lot of knowledge to work with.

This back and forth is also why I hoped for this thread to focus more on how instead of if. This way we can approach an impossible goal in workable steps and we all can contribute whether we believe in space octopi or not.


Anyway, since Rogar Demonblud pointed out the energy requirements for a viable technological progress, I will put that on my list:
4. Energy sources.


Something to consider in the context of interesting tools I want to throw here are the pistol shrimps, which are able of creating extreme pressures and temperatures if only in a small spot for a very short time. Since this is done by purely mechanical means, it might be possible to replicate even with low technology level. Precision will be an issue for such a machine, but it is difficult for me to tell, if it would make the task impossible or not. At the very least pistol shirmps themselves could be used as tools maybe and bread for this very purpose. The key question here is, is the cavitation gun scalable? If it is, then there might be a true alternative to fire for material processing. Not as efficient maybe, but with much higher peak temperatures being possible.

[Lord Torath]

Without modern technology, we cannot have modern life, and once we lose it, even if only for a short while, we're slowly going back towards the Stone Age.

Stone age? No. I'll give you the early industrial age, though. I'd imagine we'd almost instantly have charcoal makers and kilns and early forges, assuming anyone with knowledge of the basic processes survives. I'll refer you to How to Invent Everything: A Guide for a Stranded Time Traveler for a thought experiment about how quickly you could reconstruct modern technology starting from almost nothing.

On the original topic, I could easily see intelligent undersea life developing written language, and thus culture and civilization. They could easily attain stone-age technology.

I don't see them getting any further, though. There is so much chemistry it is impossible to do underwater. Water is a huge heat sink, instantly draining heat from high-temperature reactions, making metalworking impossible. It's also a very good conductor of heat, quickly transferring that heat to the nearby surroundings. In the event you decide to use an undersea volcano to heat your metal, you'll never be able to get close enough to do something useful with it. It would be like a human trying to forge metal while standing inside the blast furnace. You are limited to temperature extremes of about -4^o to 120^o or so. Anything requiring temperatures outside that range is just not happening. Anything near the extremes will be exceedingly difficult. Anything involving gasses will also be extremely difficult.

Transparent materials are almost certainly a no-go. I mean, yes, you can get obsidian when lava cools just right, but you have no way of controlling that, since you can't get close enough to the lava without cooking yourself. Plastics also require heat, both for refining petroleum and for casting, eliminating another class of clear solids.

Edit (Ninja'd by Radar): Mass use of pistol shrimp could conceivably change some of the above. If you could build gears and propellers, you could build a cavitation machine.

[Tvtyrant]

Energy generation from deep sea vents would be fairly easy, their civilizations might be more focused around those to begin with. Even if all they get out of it is the turning of simple watermill designs that would still be a lot of utility.

Electricity I don't think would be as easy, wiring would be a lot more difficult to build and maintain there. On the other hand radioactive materials are a lot safer, so if they get a hold of uranium they could use it more freely.