There's an African folktale that tells the tale of how all the stories in the world were lost, and then recovered. I can't recall this tale in detail but think one of the Magic Cellar episodes was based on it. Or maybe I read the story somewhere.
Perhaps the story illustrates an actual event - one where the entire (village?) populace forgot their stories or history and needed a concerted effort to recall the lost memories. Perhaps it illustrates a fear that the oral histories can get lost and served to reinforce the importance of passing on the stories. (Too bad it didn't drive the development of some sort of writing.)
Today, there's a collective amnesia around the African folktales I grew up with. I thought it was just me...I almost remember the stories but they're just out of my grasp. I think if I think deeply enough, they will come back. So I throw out the little bits I remember and ask others to fill in the holes. I see eyes light up as they remember the story...they think they remember but then the story is just out of their grasp.
I've observed this often enough that I now expect it. "Oh, I will remember that one!", they say. "Shoot me an email to remind me. I will write it out and send it to you." End of story.