常數简体常数

cháng shù

The constant measures · chang shu

Also rendered: the constant measures (Keeps 數 as an amount measured out) · the regular allotments (Plainer; loses the sense of a number) · the fixed proportions (Emphasises the ratio between blood and qi) · chang shu (Bare transliteration)

Physiology

Reviewed · 2026-09

At a glance

Pinyin: cháng shù
Simplified: 常数
Literal: 常 is what holds from one case to the next — 說文 takes it from the skirt worn beneath, the garment that does not change — and 數 is what has been counted. Put together they are not a statistic but an allotment: the amount of blood and qi a channel is given, told as though it had been measured out in advance. The chapter calls it 天之常數, a constant of heaven, and the word heaven is doing real work: this is what you are born with, not what the season has done to you.
Shuowen: 《說文解字》：常，下帬也。从巾尚聲；數，計也。从攴婁聲。本篇之目：太陽常多血少氣，少陽常少血多氣，陽明常多氣多血，少陰常少血多氣，厥陰常多血少氣，太陰常多氣少血。

In brief

The opening table of chapter 24 and the one the whole chapter hangs on: each of the six channels has a fixed allotment of blood and qi, and the allotment is a fact about the person rather than about the illness. It is the reason the chapter can end with six needling rules instead of six opinions — where a channel is plentiful you may let, and where it is scant you may not. Readers should note that the graph 數 is read shù here and shuò in the chapter’s phrase for repeated fright; the two senses sit six paragraphs apart in the same text.

Senses in the classical corpus

The allotment of the six channels 夫人之常數

六經各有氣血之定分

太陽常多血少氣，少陽常少血多氣，陽明常多氣多血 — Suwen 24

Something given, not something caught 此天之常數

「天」謂稟賦，非謂天時

少陰常少血多氣，厥陰常多血少氣，太陰常多氣少血，此天之常數 — Suwen 24

The premise the needling rules rest on 剌陽明出血氣

所出者必其多者，所惡者必其少者

剌陽明出血氣，剌太陽出血惡氣 — Suwen 24

The other reading of the same graph 形數驚恐

「數」讀 shuò，屢也，與此讀 shù 者異

形數驚恐，經絡不通 — Suwen 24

Measured, not merely asserted 先度其兩乳間

本篇言俞穴，亦以度量得之，與開卷言「數」同一意趣

欲知背俞，先度其兩乳間 — Suwen 24

Occurrences in the classics

Passages where the term does real work, with the original, pinyin and English on the same line.

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1 passages

素問·血氣形志 Suwen 24 · 血氣形志 Read in context →

夫人之常數，太陽常多血少氣，少陽常少血多氣，陽明常多氣多血，少陰常少血多氣，厥陰常多血少氣，太陰常多氣少血，此天之常數。夫人之常数，太阳常多血少气，少阳常少血多气，阳明常多气多血，少阴常少血多气，厥阴常多血少气，太阴常多气少血，此天之常数。

Fú rén zhī cháng shù, tài yáng cháng duō xuè shǎo qì, shào yáng cháng shǎo xuè duō qì, yáng míng cháng duō qì duō xuè, shào yīn cháng shǎo xuè duō qì, jué yīn cháng duō xuè shǎo qì, tài yīn cháng duō qì shǎo xuè, cǐ tiān zhī cháng shù.

The constants of a person: greater yang is regularly plentiful in blood and scant in qi; lesser yang is scant in blood and plentiful in qi; yang brightness is plentiful in both qi and blood; lesser yin is scant in blood and plentiful in qi; ceasing yin is plentiful in blood and scant in qi; greater yin is plentiful in qi and scant in blood. These are the constants of heaven.

本篇開卷第一事，不是議論而是數目：太陽多血少氣、少陽少血多氣、陽明多氣多血、少陰少血多氣、厥陰多血少氣、太陰多氣少血。六經之數一定，篇末六條刺法便不是六個意見，而是由此數推出：多者可出，少者不可出。「天」字宜著眼，謂稟賦所受，非謂時令之氣。又「數」字本篇二讀：此讀 shù，下文「形數驚恐」讀 shuò，同形而異讀，讀者不可混。本篇言俞穴亦以折草量度，與此言「數」同一意趣——《內經》言身，每欲其可量，不欲其可意。

Compounds built on this term

血氣

xuè qì

blood and qi

本篇題中之義，一站另有「血」「氣」二條

多血少氣

duō xuè shǎo qì

plentiful in blood, scant in qi

太陽、厥陰之常

多氣少血

duō qì shǎo xuè

plentiful in qi, scant in blood

少陽、少陰、太陰之常

天之常數

tiān zhī cháng shù

the constants of heaven

稟賦之定分

氣數

qì shù

the numbers of qi

本站第九篇已立目（id 373），與此相近而所指不同

How it has been translated

Every rendering below is a decision about which reader is being addressed. There is no neutral option.

Wiseman & Feng	the [qi and blood] constant	They render 常 as constant and leave 數 implicit, which is defensible but loses the counted sense.
Unschuld	the regular quantities	He supplies 'quantities', making explicit that the text is talking about how much.
This site	the constant measures	數 is a number that has been arrived at, and the chapter behaves as though someone measured — it goes on to describe measuring a body with a straw. 'Measure' keeps that habit visible; 'constant' alone does not.

Entry status

Review pending — who reviews this?

2026-09

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