I was thinking on why knowledge is lost during dark ages; why important information, sciences, and techniques are just lost to time, and more importantly how that can be represented in a game.
I realized that it can be represented by the individual. A citizen can learn a technique either from their personal testing or from time spent training with someone else who knows (something like weaving, or flint napping, or even writing).
This can be represented by a lack of efficiency for simple tasks without knowledge with knowledge being increased overtime, probably with some rating to it like novice, mediocre, adept, and master; the rate that knowledge is gained can be doubled if they work with someone who has a higher knowledge rating.
More Complex tasks cannot be done without prior knowledge, lose the knowledge and you lose the ability to do anything with it.
New techniques can be discovered by having the same citizen working the same tasks for long periods of time, most likely with a mean time to happen formula to allow for technologies and techniques to increase as they did historically without it being the exact same each time, and without advancements to game concepts that aren’t even being worked at the time.
There can also be eureka moments where gifted citizens experiment and observe something that makes them make a new technology from scratch (like agriculture)
Tech can also be discovered through trade and migrants, meeting with other cultures and how they do things.
None of this would be permanent though, if knowledge if not used by a citizen for a set period of time there will be a chance that they will lose the knowledge, maybe decreasing their rating until they completely forget it.
This fits into a dark age, because during a dark age trade and migration breaks down, there is warfare,starvation and death, and all available workers need to focus on surviving, so that over only a handful of generations the knowledge that used to be the backbone of the society is long since forgotten.
What do you think?