I made a comment a post or two ago about the Plains Indians perhaps not feeling the need for a Socrates, and just realized this is inadvertently funny: Socrates never wrote anything down. He was philosophically opposed to it. Every dialogue had a life which ended with the dialogue. That was how he liked it. We have him as a character, in Plato, and most likely in spirit, but not in his words.
How would we know if the Plains Indians had in fact produced their own Tolstoys and Aristotles and Newtons, and the history simply did not endure?
How can any of us know how much genius has happened on Earth, and gone unrecorded, the record lost, or the record unrevealed?