As a fairly totalitarian and isolationist country surrounded on most sides by geographical hindrances, China really didn't have many immigrants begging to get in.
china's early leaders limited contact with outsiders
Mountain ranges & deserts
The lesson is that the decline of a civilization is not simply the result of attack by outside invaders.
Canton
The history of civilization does not include everybody. No hunting or nomadic peoples could generate a civilization -- they lacked the stability and resources, and, with the exception of a limited numbers of signs and symbols, they never developed writing, unless it came from the outside.
china's early leaders limited contact with outsiders
Mountain ranges & deserts
During their Golden Age under the Ming Dynasty, the Chinese implemented isolationist policies such as the maritime prohibition laws to limit contact with foreign powers. They did engage in some limited trading and cultural exchanges with neighboring countries, but overall, the Ming Dynasty favored a policy of isolationism to protect their civilization from outside influences.
From outside
China worked to block outside influences. This allows them to preserve their culture without having to worry about outside influences.
Outside influences that affected the development of the Korean language include contact with China, which led to the borrowing of vocabulary and adoption of Chinese characters, as well as the influence of Buddhism, which introduced new religious and philosophical terms. The Japanese occupation of Korea in the early 20th century also impacted the language, as Korean was suppressed in favor of Japanese.
because the Chinese emperer thought that he would rather spend the money used on trading and communicating with other countries and use it on frontline defence of china.
They all developed in areas around rivers, with some geographical protection from outside invaders.
philosophers
outside - 外 (Wài)
It depends what the outside influence is.
sleeping in tents outside