Why did western philosophy decline to such an extent?

The root cause is religion. Religion is a great collection of people's thoughts, which reflects people's philosophy of life and cultural customs. Therefore, the most prominent representative of a civilization is its religion, and the competition between civilizations can be said to be religious competition in the final analysis. Any nation and civilization has religion, even if it does not appear in the form of religion. Every society has a set of rules to guide people's daily life. This set of rules is called unwritten morality and written law, and the combination of the two is actually religion.

Far from saying that the religion of Arab countries is a typical Islam. The backwardness of Arab society is the backwardness of religion. Why is religion backward? I quote a passage from Tocqueville: "Religion. . . . . . Don't go beyond its inherent scope, because if religion wants to extend its power beyond religious affairs, it is in danger of breaking its promise in all matters. Therefore, religion should pay attention to defining its own range of activities. Only within this range can it exert influence on people's spirit. Outside this range, it is completely free.