Why is physical and economic geography considered an integral science?

Previously, geography was one holistic science, which was engaged in studying the structure of our planets, its population, economy, countries and borders, as well as physical properties. Now there are two directions, economic and physical geography. But this is all one science, because economic geography often depends on physical geography; physical position can greatly influence the economies of countries. So that these are two large subsections of one science, and not different.