信 xìn · 义 yì · 相 xiàng · 假 jiǎ · 类 lèi — from the Zuo Zhuan, 706 BCE
The oldest systematic theory of naming in China is found in the Zuo Zhuan (左传), one of the foundational texts of Chinese historiography, traditionally attributed to Zuo Qiuming of the Lu state (c. 5th century BCE).
In the sixth year of Duke Huan of Lu (706 BCE), the Duke's son was about to be born. Duke Huan asked his minister Shen Xu (申繻, shēn xū) about the principles of naming. Shen Xu's reply — the "Five Principles" and "Six Prohibitions" — became the foundation of Chinese naming theory for the next 2,700 years.
"To name from what is innate." The child is named after visible birthmarks or natural signs at birth — hand patterns, footprints, birthmarks, or unusual omens. Shen Xu gave examples: Shu Yu of Jin was named 虞 because his palm had lines resembling the character 虞; Ji You of Lu was named 友 because of a "友"-shaped hand pattern. This is xin: using the body's own marks as testimony.
"To name from virtue." The child is given a name embodying moral ideals — the parents' hopes for the child's character. Characters such as 文 (cultured), 武 (martial), 德 (virtue), 仁 (benevolence), and 义 (righteousness) are classics of this tradition. Nearly all modern Chinese virtue names descend from this principle.
"To name from likeness." The child is named for physical resemblance to something or someone. (Some scholars distinguish this from xin by noting that xin refers to innate marks, while xiang refers to overall appearance and resemblance to external objects or people.)
"To take from objects." The name is borrowed from the external world — mountains, rivers, plants, tools, animals. Shen Xu's example: Confucius named his son 鲤 (carp), courtesy name 伯鱼 (Elder Fish), because Duke Zhao of Lu had presented Confucius with a carp. The gift became the name — this is jia.
"To take from the father." The name draws from traits associated with the father — a character from the father's name, something the father excels at, or a concept linked to the father's identity. The idea is that the child resembles and continues the father's legacy.
After the Five Principles, Shen Xu laid out six things a name should not be drawn from: names of states, official titles, mountains and rivers, illnesses, livestock, and ritual vessels. The reason: the Zhou people "served the spirits through taboo" (以讳事神) — after death, a person's name must be avoided. If you named a child after a state or title, that state or title would have to be renamed upon the child's death — a disaster for governance and ritual.
This is the theoretical origin of the Chinese name taboo tradition. For more on how taboos evolved over two millennia, see Naming Taboos.
Shen Xu's Five Principles and Six Prohibitions are the earliest systematic framework for naming in Chinese civilization. Two principles in particular — "naming from virtue" (义) and "borrowing from objects" (假) — remain the most common approaches to Chinese naming today. The taboo consciousness embedded in the Six Prohibitions evolved into the elaborate avoidance system that shaped Chinese writing, speech, and ritual for over two thousand years.