In your paragraph about medieval doctors, you erroneously left out the fact that it was not "European and Islamic" doctors that were trading technique, it was *Jewish* doctors that were trading techniques with Islamic doctors, while most of the non-Jewish European population was barely literate, much less versed in advanced scientific techniques. The various European [royal] court physicians were either Jewish or Islamic since both had been practicing medicine with the benefit of medical knowledge that they had known and taught for centuries by that time, information that the christian world is just now finding out about through their own research.