Classica Sinica Medica

奇偶

qí ǒu

The odd and the even · qi ou

Also rendered: The odd and the even (this site; 奇 is the number that cannot be halved, 偶 the pair, and both are counts of the whole formula) · Odd and even formulae (clearer in English, and the chapter's own word is a pair of numbers, not a pair of formulae)

Core vocabulary

Reviewed · 2026-10-14

At a glance

Pinyin
qí ǒu
Simplified
奇偶
Literal
奇 jī — a number that cannot be halved, the odd; 偶 ǒu — a pair, the even. The chapter counts the drugs in a formula and calls the formula odd or even by the number it comes to: 君一臣二 is three and so odd, 君二臣四 is six and so even.
Shuowen
**《說文》：奇，異也，一曰不耦；耦，耒廣五寸為伐，二伐為耦**，耦即偶。**「奇」字本篇7見，「偶」字本篇8見**；**「奇偶」連言一見於「近而奇偶」「遠而奇偶」**；**「奇之制」與「偶之制」各2見**；**四制之數俱在本段：君一臣二、君二臣四、君二臣三、君二臣六**

In brief

The odd formula and the even one, told apart by the number of drugs in them: 君一臣二，奇之制也；君二臣四，偶之制也；君二臣三，奇之制也；君二臣六，偶之制也. The count is of the whole formula, not of any one rank — 君二臣三 is five and odd though it has an even lord — so 奇 and 偶 are properties of the number a formula lands on. Which of the two to use is then given as a rule of distance: 近者奇之，遠者偶之, 汗者不以奇，下者不以偶, and the size of the dose answers to it — 近而奇偶，制小其服也；遠而奇偶，制大其服也；大則數少，小則數多. The pair is thus the chapter’s arithmetic of prescriptions, and it is the thing that fails first: 奇之不去則偶之，是謂重方.

Senses in the classical corpus

1
The two 奇、偶
奇者數之不耦，偶者數之相耦
奇之制也 — Suwen 74
2
Its measures 君一臣二、君二臣四
合數定奇偶
君二臣四，偶之制也 — Suwen 74
3
The other two 君二臣三、君二臣六
一奇一偶，四制乃具
君二臣三，奇之制也 — Suwen 74
4
How to choose 近者奇之，遠者偶之
遠近定奇偶
近者奇之，遠者偶之 — Suwen 74
5
The exception 汗者不以奇，下者不以偶
汗下二法不用其常
汗者不以奇，下者不以偶 — Suwen 74
6
Its dose 近而奇偶，制小其服
遠則制大，大則數少
制小其服也 — Suwen 74

Occurrences in the classics

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

Display
1 passages
Suwen 74 Suwen 74 · 至真要大論 Read in context →
故曰：近者奇之，遠者偶之，汗者不以奇，下者不以偶。補上治上制以緩，補下治下制以急。急則氣味厚，緩則氣味薄，適其至所，此之謂也。病所遠而中道氣味之者，食而過之，無越其制度也。是故平氣之道，近而奇偶，制小其服也；遠而奇偶，制大其服也。大則數少，小則數多。多則九之，少則二之。奇之不去則偶之，是謂重方。 故曰：近者奇之，远者偶之，汗者不以奇，下者不以偶。补上治上制以缓，补下治下制以急。急则气味厚，缓则气味薄，适其至所，此之谓也。病所远而中道气味之者，食而过之，无越其制度也。是故平气之道，近而奇偶，制小其服也；远而奇偶，制大其服也。大则数少，小则数多。多则九之，少则二之。奇之不去则偶之，是谓重方。
Gù yuē: jìn zhě jī zhī, yuǎn zhě ǒu zhī, hàn zhě bù yǐ jī, xià zhě bù yǐ ǒu. Bǔ shàng zhì shàng zhì yǐ huǎn, bǔ xià zhì xià zhì yǐ jí. Jí zé qì wèi hòu, huǎn zé qì wèi bó, shì qí zhì suǒ, cǐ zhī wèi yě. Bìng suǒ yuǎn ér zhōng dào qì wèi zhī zhě, shí ér guò zhī, wú yuè qí zhì dù yě. Shì gù píng qì zhī dào, jìn ér jī ǒu, zhì xiǎo qí fú yě; yuǎn ér jī ǒu, zhì dà qí fú yě. Dà zé shù shǎo, xiǎo zé shù duō. Duō zé jiǔ zhī, shǎo zé èr zhī. Jī zhī bù qù zé ǒu zhī, shì wèi chóng fāng.
Hence it is said: what is near, use the odd; what is far, use the even; what is to sweat, do not use the odd; what is to carry down, do not use the even. To supplement above and treat above, make the rule slow; to supplement below and treat below, make the rule urgent. When urgent the qi and flavour are thick, when slow they are thin; suiting where it arrives — this is what is meant. When the seat of illness is far and the qi and flavour is consumed on the way, take it after eating and pass it through, and do not overstep the measure. Therefore in the way of levelling the qi: near and odd or even, make the dose small; far and odd or even, make the dose great. The great takes few in number, the small many. When many, nine of them; when few, two of them. If the odd does not remove it, then the even — this is called a doubled formula.
**「奇偶」本篇連言二見，皆在此段：一在「近而奇偶」，一在「遠而奇偶」**；**「奇之制」「偶之制」各2見，俱在前一段**；**四制之數：君一臣二、君二臣四、君二臣三、君二臣六**；**此段以「是故平氣之道」領之，其數之奇偶以合數計，非以君臣分**

Compounds built on this term

奇之制
qí zhī zhì
the odd rule
本篇2見；君一臣二、君二臣三皆屬之
偶之制
ǒu zhī zhì
the even rule
本篇2見；君二臣四、君二臣六皆屬之
重方
chóng fāng
the doubled formula
本篇一見；奇之不去則偶之
制小其服
zhì xiǎo qí fú
make the dose small
本篇一見；近者以此

How it has been translated

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

This sitethe odd and the eventhe arithmetic of a prescription, decided by the number of drugs and by the distance of the disease
Literalthe odd and the evenexact, and it needs the context
Descriptivea formula of odd count against one of even countclear, and too long to stand where the chapter says 近而奇偶

Entry status

Review pending — who reviews this?

2026-10-14

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