What do quadrangles in Beijing symbolize?

Beijing quadrangle building is the carrier of China traditional culture. From the overall pattern to the detailed decoration, from the layout of primary and secondary houses to the definition of the inside and outside of the courtyard, from the orientation of the gate to the layout of wells, stoves and toilets, all of them reflect profound cultural connotations.

The Closure of Doors and Walls —— Old Beijing's "Besieged City" Complex. The economic foundation of China feudal orthodox culture is closed and conservative small-scale peasant economy, and the architectural reflection of this economic form is the prevalence of doors and walls.

There is a great difference in mentality between farming people and nomadic people. Sima Qian commented on the Huns, saying that "the water plants migrate, and the city will always plow the fields", "If it is favorable, it will advance, if it is unfavorable, it will retreat, and if it is not ashamed, it will flee" (Biography of Xiongnu in Historical Records). Because northern nomads themselves don't like to settle down, grazing cattle and sheep can't settle down. If you go to war with neighboring countries, once you lose, take your wife and children, drive cattle and sheep, and walk away. There is no loss for them. The most is to change the pasture in advance. Therefore, nomadic people are not ashamed of losing, and their concept of territory is relatively weak.