Discussing about the millennia-long stability of Chinese ancient architecture which lies in wise scientific design and craftsmanship. Wu Xing, the Five Elements (Metal, Wood, Water, Fire, and Earth) is an important concept in ancient Chinese philosophy, representing the fundamental elements and dynamics of the universe. Among them, "Metal restrains Wood," symbolizing rusting metal can corrode wood, leading to damage in wooden objects.

Therefore, ancient Chinese carpenters avoided using nails when constructing wooden buildings and furnitures. Instead, they employed pure wooden joinery techniques known as sunmao, relying solely on mechanical principles for physical connections, which proved to be even more durable.