And that is hardly a fact. It is one theory of the why. It was posited by Edward Gibbon, and his books are widely heralded for his use of primary sources. As in he used contemporary writings instead of the Church's Latin translations (which are at best secondary sources). It was apparently one of the first historical works to do this, which in my opinion lends undue credence to his theory. This undue credence is (again IMHO) based on the quality of his work instead of the accuracy of his conclusion.


I could (probably) come up with other example of scientists doing fantastic and thorough work only to come up with bunk conclusions or conclusions highly slanted by other motivations, but I'm all tuckered out for now.