Your reference to Romans 7:7... I had forgotten about that verse and it changed my thinking about disagreeing with your premise. Still, at the end, you assume everybody has The Ten Commandments written on their walls. In Paul's discussion of the matter, one must keep in mind his whole life was surrounded by the Law of Moses. He was a thoroughly educated Pharisee. This certainly doesn't negate your whole essay, nor Romans 7:7, and I do agree that if "pagans" don't listen to their own natural conscience, I would add that a Sodom and Gomorrah scenario might arise.