Pei Xiu

Pei Xiu's six principles (also called the Six Elements of Mapmaking) covered concepts including consistent scale, a rectangular grid system for locating places, proper mapping of roads and distances, and methods for representing elevation and terrain features. These principles were outlined in his preface to the Yu Gong Regional Map and established a scientific framework that influenced Chinese cartography for centuries.

Pei Xiu served as a high-ranking official and cartographer during the Western Jin dynasty, which lasted from 265 to 316 AD. He held the title of Minister of Works and produced the Yu Gong Regional Map, which compiled geographic knowledge from across the Jin empire's territories.

Pei Xiu's rectangular grid system became the foundation for Chinese mapmaking for over a millennium, directly influencing later cartographers who produced large-scale atlases using grid-based coordinate methods. This approach predated similar grid-based cartographic standards in Europe and demonstrated a sophisticated understanding of projecting curved terrain onto a flat surface.

Pei Xiu's most significant cartographic work was the Yu Gong Regional Map (Yugong Diyutu), compiled from older texts and field reports, along with a companion text called the Territorial Map of the Ba-Jin Region. The original maps have not survived, but his preface detailing the six principles was preserved in the Book of Jin (Jin Shu), allowing scholars to reconstruct his methods.