Trolls and rocks
Once upon a time long ago after a mountain came into cave and decided to have diner. For protection a smart guy decided to move a rock in front of its cave. It was hard labor and not really efficient as in the end he was locked out of his own cave.
The guy living next to him thought this was a really good idea but it needed work. So he thought about it and came out with a solution. He made the rock round and found himself quickly locked out, not being all that healthy he was found the next day half eaten.
Everyone was laughing at the two idiots. Came a third one who thought that it was not the idea that was the problem but the material. He used a large piece of wood and it worked. He locked his cave and promptly died, inside.
The fourth one thought long and hard. After trying to figure it out and nearly die in the process, still coughing he realized that the smoke was at fault. He created a small opening to let it escape. He lived happily in there and other folks who were laughing so hard at the initial attempts started to do use doors.
Came winter and half the population died. Lucky guy, the fourth guy died too otherwise he would have been torn to pieces, alive. It did not really matter that they tore him apart anyway but I am sure he did not care.
A fith guy unwilling to let this new security go away took the time to observe the cave entrances and discovered that all folks who died had piled dirt against their door to avoid cold drafts inside the cave. He did not know why but figured out that was the problem.
He moved into his cave despite other folks telling him he was going to die. The following winter was a rough one. More folks died of cold than anything else, they had removed their doors, the beast outside had frozen dinners while watching the naked cold monkeys, all the while taking bets as to who would drop next. Our fifth guy did not remove his door. This interesting state of affair went on for a couple of years, you know winters were really harsh back then. He and his family thrived while the others kept being cold and dying many becoming snack food for the ever roaming beasts.
Folks came to see him and asked why he was not dying like every other fools before. He did not know other than having cold air coming into his house all the time. To really stay warm he had to keep his clothes on but the temperature was clement inside so...
Everyone followed his example and so it went for a while.
The creatures outside howled, scratched and kicked but there was no more snacks to be had. They did not lose much thought, raw smocked food is not all that good anyway but still, they were disappointed. They moved on to another monkey gathering who did not have idiots.
A few decades later due to a god's anger some caves were destroyed completely, other partially and yet some left intact. One cave was avoided by all, for days: a thin voice cried out for days until it weakend and finally fell silent. One guy who had his cave partially destroyed created a platform to sleep on. Soon he was too hot and removed his clothes.
He found a new cave to live on. The very first night he was cold and kept his clothes on. Uncomfortable now he went on to understand why. The only thing he saw between his old cave and his new one was that he had used the debris to create a platform. Now intrigued he created the same thing in his new cave and slept like a baby. He did not think anything of it, no one asked him, beside he had a bad temper and had broken a few skulls just 'because'.
The bed had to wait a few hundred years before it was reinvented by a woman tired of sharing the floor with mice and other unsavory critters but that is another story.
If you were patient enough and read all this non-sense you may have understod a couple of things that we all know and accept for granted.
This is simply to show that while not knowing a damned thing the folks involved into this weird story created a door for protection, a ventilation system and finally an elevated platform. They were the idiots of their time.
The trolls in there? I let you figure out who they are.
