The title is a bit over dramatic but, per the title, if you could contribute with one piece of knowledge to a book that every single individual should learn from in order to kickstart a civilization, what would be yours?
My personal choice would be the process of soap making, from scratch.
I’d explain LGBTQIA issues, personal and community acceptance of those born different.
Ancient people were much more accomodating towards those who were different.
Many so called “primitive” people reserved special roles for such individuals: xamans, oracles, etc. Their difference made them special, as if favored by whatever gods or spirits were reveared.
I read a very interesting book in my teens, essentially an anthropological/ethnological treaty, where the current obcession with difference was a creation from the 18th century.
