What is civilization ?
It is clear. Man discovered bronze. Keepable
Then war. Instinctive , especially in hunger time.
Then civilization regression in case of war or just unjustice. This, only memory based on writing could keep/embed. So!
Now, the contrary occurs. The human collective memory , that determines group behavior, records the above-mentioned lessons and wisdom, and others about universal well-being and global and regional interaction and unity of fate ( through just observation, travel, trade, international cooperation, among other features ). But in many cases, mandated trusted potents manage to erase or occult that info/memory , showing just bits of it when it is needed, especially to save themselves in case ! ! In many cases, from 1930's till now, this was thé path to many disasters, from epidemics to nazism.
Of course, the fact that something exists is nothing in itself. (Like fossils that where always under few centimeters of dirt from millennial times and we just couldn't uncover or study them ). The most part of value in both material resources and ethical/moral behavior lies in the fact that we know about it ! ( In time, with enough budget handy. But this is other global phantasm.. sorry:story.)