三常

sān cháng

The three constants · san chang

Also rendered: The three invariables (keeps 常 as what does not shift, and strains English) · The three standing questions (clear as procedure, and it drops the word 常)

Core vocabulary

Reviewed · 2026-10-17

At a glance

Pinyin: sān cháng
Simplified: 三常
Literal: 三 sān — three; 常 cháng — what holds, the constant, as against what shifts. 診有三常 is not three rules of thumb but three things a diagnosis must always ask, before it asks anything of the body.
Shuowen: 《說文》：常，下帬也，借為恆久。「三常」本篇1見：「診有三常，必問貴賤」；「常」字3見：「診有三常」「亂至失常」「是謂失常」，後二處皆言失其常度，與此為診法之常者別。本篇三常，就文觀之，謂貴賤、貧富、苦樂三者，故下文歷舉封君敗傷、欲侯王、始富後貧諸事。

In brief

Three things a diagnosis always asks, and all three are histories rather than signs. 診有三常，必問貴賤 — the first is rank: was this man enfeoffed and then ruined; does he want to be a marquis or a king; was he noble and has he lost his power? Though no evil strikes him, his spirit is injured within and his body will fail. The second is wealth: was he rich at first and poor after? Though no evil injures him, his skin is scorched, his sinews bend, and he wastes and stumbles into contraction. The third, which the chapter carries into the same sentence, is the temper that comes of these turns — the joy and hardship, the grief and fear that follow a change of station. The point is the one the five errors keep making: the illness is in the history, and a physician who examines only the body will not find it.

Senses in the classical corpus

Three things always asked 診有三常

貴賤、貧富、苦樂

Noble and base, rich and poor, bitter and joyful.

診有三常 — 素問·疏五過論

Rank 必問貴賤

貴賤異勢，則志意異

Station differs between noble and base, and so do intent and will.

必問貴賤 — 素問·疏五過論

Enfeoffed and ruined 封君敗傷

嘗貴而敗，其傷在神

To have been noble and then fallen wounds the spirit.

封君敗傷 — 素問·疏五過論

The would-be lord 及欲侯王

欲而未得，其傷亦在神

To desire and not obtain also wounds the spirit.

及欲侯王 — 素問·疏五過論

Rich then poor 始富後貧

皮焦筋屈，痿躄爲攣

Skin scorched and sinews bent, flaccidity turns to cramping.

始富後貧 — 素問·疏五過論

Losing the constant 亂至失常

醫不能嚴，則常度亂

When the physician cannot be strict, the constant measure is thrown into disorder.

亂至失常 — 素問·疏五過論

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·疏五過論 Read in context →

診有三常，必問貴賤，封君敗傷，及欲侯王，故貴脱勢，雖不中邪，精神内傷，身必敗亡。始富後貧，雖不傷邪，皮焦筋屈，痿躄爲攣。诊有三常，必问贵贱，封君败伤，及欲侯王，故贵脱势，虽不中邪，精神内伤，身必败亡。始富后贫，虽不伤邪，皮焦筋屈，痿躄为挛。

Zhěn yǒu sān cháng, bì wèn guì jiàn, fēng jūn bài shāng, jí yù hóu wáng, gù guì tuō shì, suī bù zhòng xié, jīng shén nèi shāng, shēn bì bài wáng. Shǐ fù hòu pín, suī bù shāng xié, pí jiāo jīn qū, wěi bì wéi luán.

In diagnosis there are three constants: one must ask of noble and base, of him who was enfeoffed and then ruined, of him who would be a marquis or a king. One who was noble and has lost his power — though no evil strikes him, his spirit is injured within, and his body will surely fail and die. One who was rich at first and poor after — though no evil injures him, his skin is scorched, his sinews bend, and he wastes and stumbles into contraction.

「三常」本篇1見；「診有三常，必問貴賤」以下，歷舉封君敗傷、欲侯王、始富後貧三事，即三常之目；四過之案由此而立。

Compounds built on this term

三常

sān cháng

three constants

本篇一見

貴賤

guì jiàn

noble and base

三常之首

封君敗傷

fēng jūn bài shāng

enfeoffed and then ruined

三常之目

失常

shī cháng

losing the constant

與三常相對為文

How it has been translated

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

This site	the three constants	three histories every diagnosis asks
Literal	three constants	exact, and it does not say of what
Descriptive	the three questions of rank, wealth and temper	clear, and longer than the text

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2026-10-17

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