Walter: Well, there are many, many books on this subject. Another one: Rodney Stark's recent "For the Glory of God: How Monotheism Led to Reformations, Science, Witch-Hunts, and the End of Slavery," by Princeton U Press.  Another: Charles Murray's "Human Achievement." With those above, that's 4. As well as copious Internet research. Of course, it's not just "knowledge," but what one does with it. The ancient Greeks in the end were "stillborn" on science. It just ended. As did Islamic science. Whereas science since the Catholic Middle Ages has been a going concern because Catholics developed scientific method. It's religion, specifically the Catholic Religion, that gave people a reason and a way of thinking that made science a going concern. In particular, as all these scholars pointed out, St. Thomas Aquinas solved the problem of faith vs. reason by showing there was no conflict, and where conflict seemed to exit, it really was limited human knowledge that needed to be advanced.