According to an old Beijing saying “Inside 9, outside 7, 4 Imperial City (inner part of Beijing)” is referring to 9 gates, 8 places and one center.

“Inside 9， outside 7”: Inside there is the city (center) and outside there are the city gates.

“Inside 9” are: In the East （1）Dongzhimen,（2）Chaoyangmen. In the West （3）Xizhimen and（4）Fuchengmen. In the North（5）Deshengmen
（6）Andingmen. In the South（7）Chongwenmen，（8）Zhengyangmen (today Qianmen) and （9）Xuanwumen.

“Outside 7” are: In the Mingdynasty, Jiajing Emporer (嘉靖) starting the citydefense, took 32 years of building the outside gate. The “3 front gates” (前三门”) are in the North, East and West. In the East and West there are (4)Guangqumen, (5)Guanganmen. In the South there is on the left (6)Anmen, on the right of Anmen and Yangmen there is （7）Yongdingmen.

The 4 gates of the inner Imperial City (inner part of Beijing): In the East there is （1）Donganmen (nowadays Donghuamen), in the South （2）Tiananmen, in the East there is （3）Xianmen, in the North （4）Dianmen.

“Inside 9, outside 7”: The “Inside” refers to “close”, the feeling of closeness and familiarity. “Outside” refers to “Overseas”, to those of Chinese heritage living outside of China and in addition how we go beyond the question of identity towards relating to one another.

Number 7: A Pre-Qindynasty saying “Your Soul is melting together and departing afterwards”: 7 days is one unit, one unit of seven days to form your spirit. After your birth 49 days, 7 circles, your 7 spirits are completed. After 49 days you are completed with your soul and spirit, and after you dye your soul is continuing。

References to 7 in Chinese Culture: Yin Yang and 5 elements they are called Seven Regulators. People are given Yin Yang, 5 elements so they have the 7 emotions。 7 can explain the Dao (道) of the World and the Qi (气) of the people. In the book 《易·系·复》it says 7 days is one circle and in the book《礼记·檀弓上》it says People who don’t drink and eat 7 days, cannot continue to live.

Number 9: 9 is the biggest number, so if there are two 9 together, you are returning to the beginning。 It’s not the original beginning, because a new circle is starting. It represents the philosophy of Dialectical Materialism “the recognition of anything”. A Buddhist saying: Two 9 together means to go back to the beginning, completing a circle, to receive a good result. The returning to 9 means: The biggest number in order, but also the ending。 That means you have to go through 1, 4,7 3,6, 9， to achieve anything. You have to complete several steps to continue.

The saying“九九归一”derives from where you’re form and leads you to where you want to go. When you you have returned, you continue, a new circle is starting.