Answer:
by preserving ancient sources of knowledge and information
Step-by-step explanation:
In the Byzantine empire were found many interesting documents from ancietn sources liek the greek phillosophers that made it possible for modern historians to preserve the knowledge of the old greek, roman and other phillosophers and scientists, they were also very good at preserving and writting documents on the scientific advances that they and other cultures had. So the answer would be preserving ancient sources of knowledge.