The author states jazz is deeply rooted in the Black experience. Not to mention, you can't invent a key. A key exists whether you're capable of producing it or not. There's this habit of believing you invented and discovered things that other people already knew about. There's no proof that Europeans were the first to string those cords together. Did it have influence on Blacks? Sure, but that doesn't take away from the fact that the art form was born out of the Black experience as the author said. Those Europeans who "invented" the key didn't in turn start making blues or jazz.