So, imagine you live in a very humid climate.

Much more than any tropical country. Fire doesn't appear in natural circumstances or, if it does, goes out extremely quickly. It's kind of a folk tale until by chance someone lights up some of it in a particularly dry building. In those circumstances, how would fire affect technology? I assume people would prioritize specific developments -weapons, certain things needed for survival in winter-, but I would like some input by more knowledgeable writers.

  • $\begingroup$ Generally, fire is mostly used in very dry areas already, given it's very destructive capabilities. People like to keep it in places where it can't be destructive and destroy things. $\endgroup$ – Halfthawed Jun 15 '20 at 16:20
  • 4
    $\begingroup$ Humidity wouldn't be an issue for a winter climate, the moisture would precipitate. Your world would need to be very warm and ultra-tropical everywhere. Even then, there's some handwavium in blocking almost all fire. $\endgroup$ – DWKraus Jun 15 '20 at 16:21
  • $\begingroup$ @DWKraus, what about low oxygen level? $\endgroup$ – user28434 Jun 15 '20 at 16:28
  • $\begingroup$ @user28434 that's not a bad thought, although I was just going with the humidity premise. You'd need to adjust how plants metabolize, since I would guess this world would look like a huge version of the Amazon. Maybe some sort of geological sink for oxygen? Usually if intelligent animals can breathe, fire can burn (very general rule, admittedly...) $\endgroup$ – DWKraus Jun 15 '20 at 16:33
  • 1
    $\begingroup$ I see two distinct questions here: 1) How would civilization develop and learn to use fire in very moist tropical climate? and 2) How would civilization develop if they can't have widespread use of fire (for whatever reason)? $\endgroup$ – Alexander Jun 15 '20 at 18:05

Humidity is not enough

Even when humidity is nearing 100% saturation, you can still start a fire. What does make fires hard to start is rain... lots and lots of rain. When it rains, would be firewood becomes nearly impossible to light using primitive means for the next 1-5 days. Also, it has to be rain, not snow. The moisture from snow does not seep into the wood; so, if you have snow capped mountains, your people could just go up to the mountains to collect firewood. So for your world to act like you want you need the whole planet to be constantly hammered by liquid rain. This is nearly impossible on a world that looks like Earth; so, your planet will need nearly all of its land mass isolated to the tropical zone with short mountains and a fairly small axial tilt to prevent your people from experiencing colder-drier seasons, rain shadows, or snow capped mountains where they could make fire.

Without fire, you loose out on several really important early inventions

1- Metallurgy: Without metal tools, you are stuck in the stone age. Without metal tools, agriculture becomes so labor intensive that you can not reliably sustain yourself off of farming it in most regions. If you can not stop to farm, you can't build a very large or advanced civilization.

2- Ceramics: This is not just pots and cups, but bricks to. Your people will still be able to make wicker baskets for holding dry goods and use hollow gourds to store liquids, but lack of bricks makes creating permanent structures in tropical areas where exposed stone may be rare virtually impossible.

3- Mortar/Concrete: The active ingredient in early forms of mortal and cement is quicklime which you need to scorch limestone to get. Between this and lack of bricks, making large permanent structures becomes a lot harder. Add to this a lack of metal tools, and shaping stone into stable stack able bricks is nearly impossible anywhere. Stone with mud mortar or compressed earth construction will make mostly permanent buildings in dry areas, but since you don't have dry areas, you are basically stuck living in building made out of wood, leaves, and grasses.

4- Fire-hardened wood: fire is often used as a way of hardening wood for various purposes. Especially since you are in a humid environment, this means your spears, axes, and hammers will break more easily, and bows might not even be possible to make.

5- Hide-glue & tree resin glue: Not only were these early adhesives the only kinds of glues available throughout most of history, but they were also important water proofing agents. If you can't boil hide or tree sap, you can't make glue; so, this means you can't make leak proofed water skins, you can't make composite bows and even adding wooden handles or shafts to stone tool heads becomes harder since the bindings were often hardened and secured with a layer of glue.

6- Fire-boaring: Another common way to fix a stone head to a wooden handle involves using fire to "drill out" the hole you need. Without fire boaring or glue, the only way you have left to attach stone to wood is by tieing it in place which is not particularly reliable.

7- Leather, raw hides, and furs: Animal pelts that are not fully dried (usually by sun baking or smoking) will begin to rot within a few days.

The end result here is that most people would remain nomadic. Nomadic civilizations are inherently size limited because they can only feed people based on the natural densities of available food sources. This size constraint also means you will never have enough minds in one place to really advance very far. The few places you could farm well enough using only wooden tools would be impossible to fortify well without shapeable stone or brick walls. When you look at the late stone age, early towns that did not have strong walls were routinely overrun by nomads; so, without the ability to make these stone walls, any attempts at early sedentary civilizations would tend to fail.

In short, not only are you stuck in the stone age, but the early stone age at that.

Now let's look at the lucky civilization that can start a fire

In our own history, various estimates indicate that it took somewhere between ~300,000 and ~2 million years to get from the discovery of fire to cook and stay warm to the use of fire as the foundation for all these other important technologies. Some of that time may have been evolution happening requiring our brains to be capable of becoming creative enough to make these leaps forwards. However, with so few humans in your setting being able to make fire, not only is accidentally finding better uses for fire harder, but you also take away most of the environmental pressure that made human creativity so selectively fit in the first place. In our own history, the hominids who could find the most uses for fire pushed out the other races, but on your world, the faster, stronger, healthier hominids will win out nearly every time; so, even those few places with enough pressure to push intelligence forward will likely see so much diffusion into the dumber surrounding populations that they will never get very far.

The only way I can see to solve for this is to isolate a population. Perhaps there is a large island away from the tropical zone which is mostly dryer than the rest of the world and cut off from moister areas. In this case fire using humans could evolve separately from the fire-less ones. Then when they go to expand to the rest of the world, they could bring things with them like metal tools and tinder kits. By bringing tender kits, and metal tools, they could craft stoves that would isolate the fire from moisture, and the tender kits would allow them to start fires on damp wood. Once they have the fires going, they could then make more tender kits, more tools, more bricks, and all the other stuff that our own ancestors were able to spread to the rest of the world.

One last thought

Even all these ideas to make your setting works may all be in vain if your humans are cleaver enough to simply prepare dry storage areas for thier wood. Using only stone tools, one can make an elevated covered structure that would allow wood to dry out enough to use, even in a place that rains all the time.

  • 1
    $\begingroup$ You don't need mortar to build with stone; a number of civilizations have demonstrated this, and their buildings are still around to prove it. (OTOH, I believe they had metal tools...) $\endgroup$ – Matthew Jun 15 '20 at 19:01
  • $\begingroup$ Yes, that was my point, you either needs the tools to shape stone, mortar to join it, or mud to join it and a very dry climate. The rare exceptions will be places with naturally flat stones like slate. $\endgroup$ – Nosajimiki Jun 16 '20 at 16:58
  • $\begingroup$ It took a lot longer than 2 million years, the use of fire predates our species. $\endgroup$ – John Jun 16 '20 at 18:22
  • $\begingroup$ @John The earliest proof of fire being used in a controlled manor was about 300-400,000 years ago. Other sites up to 1 million years ago suggest that fire was probably being used in a controlled manor, but not conclusively. Sites up to 2 million years ago exist, but are not conclusive at all as to whether they were intentional fire sites or not. So, unless you know something I don't, I'm pretty sure I'm already using the most optimistic projection that is generally accepted. $\endgroup$ – Nosajimiki Jun 16 '20 at 19:26
  • $\begingroup$ @Nosajimiki-ReinstateMonica That was totally my bad, it is not that fire is older, it is that homo sapiens is younger than 2 million years. I don't know why, but I saw 2 million and confused it with 2 hundred thousand. $\endgroup$ – John Jun 16 '20 at 19:45

Look to tropical civilizations: I'm being fairly general here, sorry. I'm not an expert on technology in the tropics, but you would need a very hot climate to support this level of humidity, so I'm guessing the tech would be much like what you find in the tropics. Cold climates would cause moisture to precipitate out as rain or snow, so these would be included in your "dry" areas (although if you've ever tried to light a fire in a bog, it's not easy). I picture a world like the Mesozoic, where there were tropical swamps at the poles. Over geological time, the environment and life forms would become (i think) similar to an age of dinosaurs.

  • Large predators would promote either evasion or weapon tech. Building high in the trees gets you above such creatures. Poison helps you kill them, but be careful, you're not cooking to denature the toxins. Be careful what you eat.
  • Food production would look somewhat different. There's no cooking food to partially break it down, and no cooking to kill parasites. Fire significantly increases the amount of nutrition humans can gather from the foods they eat. Try eating a raw potato. At least in a tropical environment there should be plenty of fruits to gather.
  • Obviously metallurgy wouldn't exist like anything we know today, so any metalworking would be with naturally occurring ones like gold. The Aztecs were able to do a surprising amount without heavy metal use, even making flint swords. Stone and wood would be your primary materials.
  • Fire might paradoxically become even more important due to it's rarity. Designing conditions to make it work would be the stuff of religion. Temples could come to resemble foundries, and if the educated elites held the secrets of fire, they might apply the knowledge to advancing related technology. The products of fire (cooked meat, metals, etc.) could be seen as gifts of the gods. If control of these secrets became too tight, the science could be lost as the only people who know it die (as has happened with many advances in human history). This gets into the story-telling part and is largely a matter of your preferences.
  • $\begingroup$ Also with not cooking your food is also drastically less nutritious, so the op's humans need to eat twice as much at least, which means every waking hour they have is spend trying to feed themselves. . $\endgroup$ – John Jun 16 '20 at 19:47

In the long run — there would be no difference

Fire is one of those things that give individuals and groups enormous power. Fire on your world may not be easy to come by naturally, but the first person to figure out how to harness it would (at least for a moment) rule the world.

And there are always sources of natural fire (despite not lasting very long). Lightning and volcanoes will always burn things. It's unlikely a world can legitimately have constant rain over every square inch, mountains will cause areas where fire is more likely than others. But even if we assume a constant rainy world (a worst-case assumption), fire will start under bushes, in crevasses, and at the early edges of volcanic flows (you must have vulcanism or you'll have trouble justifying your magnetosphere).

Which all means it might take longer for those cave men to figure out how to get fire going in a cave — but they will figure it out.

And once they do, you're back on track. so in the end, there's no difference.

Questions asking what would happen if a fundamental technology or resource is missing are frequently closed for being too broad — and for good reason. Those fundamental technologies are really, really, really hard to "not have." There are many ways to make things burn without fire; chemical being chief among them. Which means there are ways to achieve every technology despite losing one fundamental technology. The only consequence it it takes a little longer to get to where we are.


What technology?

You will not have humans much less technology. Fire is what allowed humans to exist in the first place. The invention of cooking and the massive increase in calories it creates is what allowed our ancestors to develop the large brains humans have, use of fire predates the Homo Sapiens for a reason.

Ignoring the problem of creating conditions in which fire is rare but humans can still live, you probably can't, those conditions would prevent humans from evolving in the first place.


Not the answer you're looking for? Browse other questions tagged or ask your own question.