I think most of genesis falls into the "stories told around the fire" category, myself. God may have inspired some or all of them, but I have written plenty of sappy poetry inspired by flowers. It was nice, and superficially accurate, but not really so much. Original sin-to me, is a story. A baby is not born sinful. The day the baby can put together concepts of good and not good, and chooses to do not good, it's innocence is gone. To me, it's all about transgression done deliberately and willfully. "I know God wants me to stay away from the tree, or that's what I've been told, but this guy has a point, and knowledge is always good, right?" That's chapter 3 in a nutshell to me.