So you are saying they all communicated information through clay tablets?They have found thousands and thousands of clay tablets in Dilmun, Ras Shamra and Sumer so somebody could read and write.
Because I am arguing that without a doubt information in antiquity was overwhelmingly communicated orally between individuals. And that whatever important lesson there was that needed to be remembered or passed down, was done so in the form of a story. So that it was memorable because that made it easier to remember and pass down or share.