The autumn fog hung low over Shanghai as Xu Guangqi slipped through the predawn streets, seeking forbidden knowledge from a foreign priest.

The Blind Scholar Who Saved Chinese Mathematics

Xu Guangqi's Secret Dawn Meeting with the Forbidden Jesuit

A Ming scholar risked everything to learn forbidden Western mathematics from a Jesuit priest, creating the vocabulary Chinese science still uses today.

The autumn fog hung low over Shanghai as Xu Guangqi slipped through the predawn streets on October 15, 1600, his scholar's robes damp with mist. He was fifty years old, a failed examination candidate three times over, and yet something burned in him that ambition alone could not explain. In a modest dwelling near the river, a foreign priest waited with books that would change the course of Chinese science.

Matteo Ricci had been in China for seventeen years, learning to dress as a Confucian scholar, to speak Mandarin with courtly precision, to navigate the labyrinth of imperial suspicion. But never before had a Chinese intellectual of Xu's caliber sought him out with such hunger. The two men sat across from each other as the candles guttered, and Ricci opened a copy of Euclid's Elements—geometry that the West had known for two millennia, but that had never crossed the silk roads.

What happened in that room over the following months would reshape Chinese mathematics forever. Xu Guangqi became Ricci's collaborator, translator, and eventually his friend. Together, they would produce the first Chinese translation of Euclid, the Jihe Yuanben, rendering Greek logic into Mandarin with su…

💡 Xu Guangqi's Chinese translation of 'point,' 'line,' and 'parallel' in geometry are still the standard terms used in Chinese mathematics textbooks over 400 years later.