Anonymous
“what happens if they lose ability of higher language” Well, you have to have books to teach a person to read and math starting with arithmetic, and so on. Basically you need all the books to home school a kid on these hard but required to rebuild a civilization, subjects. What this really means you have to have enough people in your community (a survival group is too small) to allow for a school and experimenters, builders, etc.
The store of knowledge (library) and skills must be the CORE of the community. The most important part of what the community is about. Yes, you got to grow food, and have warriors, etc, but protecting and passing on the knowledge must be the most important MISSION of the community!!!