Among the many legends of the Great Wall, none is more beloved than the story of the “Ratifying Brick” (Dingcheng Zhuan) at Jiayuguan.
The Impossible Calculation
In the 1530s, the Ming court commissioned the construction of Jiayuguan’s imposing gate tower. Master craftsman Yi Kaizhan was tasked with the project. Known for his extraordinary mathematical abilities, Yi calculated the exact number of bricks needed: 99,999.
The supervising official, suspicious of such precision, threatened Yi: “If you are off by even one brick, you and your workers will be executed.”
The Extra Brick
When construction was complete, the official arrived to inspect the tower. To his surprise, he found not 99,999 bricks — but 100,000. One extra brick sat on the gatehouse floor.
Triumphant, the official prepared to execute Yi Kaizhan. But the craftsman remained calm. “That brick,” he declared, “was placed by the gods to stabilize the wall. Remove it, and the tower will collapse.”
The official, unwilling to risk divine wrath, left the brick in place. It remains there to this day — a single brick on the west gate of Jiayuguan, a monument to one craftsman’s audacity.