This chart should look more like a web, showing the connections between the various areas. It is similar to getting an education, you can not get a complete education in one area, without dabbling in other areas. For example, the connections between theology, and religious history.
Sometimes before you can understand something you have to quantify it. These early natural philosophers were just organizing what they had learned so they could better understand it. How different is it from us today, trying to map the human genome?