Many go players have heard the story that go (or weiqi) was invented by the legendary Chinese Emperor Yao, in an attempt to improve his son, Danzhu. (It is not clear to me if Yao's plan worked.)
I do not seriously view the story as history, but a question about it occurred to me. When does this story/legend of Yao inventing go first appear in the records, relative to other legends about Yao?
My thought is this: If the go story has been part of Yao's legends from our earliest surviving documents, than we are dealing with a very old story. Who knows how far back it goes. But if, on the other hand, the go legend first appears several centuries after other recorded legends of Yao, then that would suggest (though not prove, of course) that the go legend is probably a later addition. (And sadly, it would give us even less reason to believe this particular legend.)
Comments from all are welcome. Though you probably already know who I am hoping will answer this