Qi and the meridians

What it is

Qì (氣) is the central concept of Chinese medicine and natural philosophy, and the standard English rendering — "vital energy" — is misleading enough to distort everything downstream.

In classical Chinese usage the word covers vapour, steam, breath, air, atmosphere, and the functional activity of things. It is closer to a general term for what is going on in a system than to a mystical substance. Weather has qi. Food has qi. A well-functioning organ has good qi. Translating it as "energy" imports a nineteenth-century physical concept the term never carried, and makes a natural-philosophical idea sound supernatural.

Qi is one of the three treasures: jīng (essence, the stored constitutional base), qì (active function) and shén (spirit, awareness).

The jīngluò — channels and network vessels — are the pathways along which qi is said to move: twelve primary channels associated with organ systems, eight extraordinary vessels, and roughly 361 classical points.

Where it came from

The foundational text is the Huángdì Nèijīng, the Yellow Emperor's Inner Classic, compiled around the second to first century BCE — a dialogue setting out the theory of qi, yin and yang, the five phases, and the channels.

But the earlier evidence is more interesting, and it shows a system under construction. The medical manuscripts recovered from Mǎwángduī, sealed in a tomb in 168 BCE, predate the Neijing and describe channels — but there are eleven of them, not twelve, their courses differ, and they contain no acupuncture points at all. Treatment is by cauterisation along the channel, not by needling specific locations.

That is direct textual evidence that the channel system developed over time rather than being received whole. The twelve-channel scheme with its neat correspondences to organs and its enumerated points is the outcome of a process, and we can see an earlier stage of it.

And the version taught worldwide today is much more recent than either. What is now called Traditional Chinese Medicine was substantially standardised in the People's Republic from the 1950s. Chinese medicine before that was regionally diverse and theoretically contentious, with competing lineages, incompatible doctrines and no unified curriculum. The state consolidated it into a teachable, examinable system — partly to extend health coverage to a vast rural population with few physicians, partly as a matter of national self-assertion against Western medicine.

Paul Unschuld's histories and Kim Taylor's Chinese Medicine in Early Communist China document this. The name "Traditional Chinese Medicine" is itself a twentieth-century coinage. This is not a debunking — a systematised tradition is still a tradition — but a practice presented as an unbroken five-thousand-year inheritance is presenting itself inaccurately.

How it is practised

Diagnosis by observation, listening, questioning and palpation — pulse diagnosis at three positions on each wrist, and tongue inspection — producing a pattern rather than a disease. Treatment addresses the pattern, through acupuncture, herbal formulas, moxibustion, cupping, tuina massage and dietary advice.

The same Western diagnosis may map to several different patterns, and be treated differently in each case. This is a genuine structural feature of the system and it makes trial design difficult.

What we can and cannot say

We can say no anatomical structure corresponding to the meridians has been found. Dissection, imaging and histology find nerves, vessels, fascia and lymphatics, and none of them follow the channel courses. Proposals identifying meridians with connective tissue planes have not held up.

We can say qi is not measurable as energy, and that studies claiming to detect it — by electrical skin resistance at points, and similar — have not replicated reliably.

We can say the diagnostic methods perform poorly on reliability testing. Studies in which several practitioners examine the same patient find substantial disagreement about the pattern, which is a serious problem for a system in which the pattern determines the treatment.

We can say the tradition is nonetheless real, textually deep, and worth understanding on its own terms. It accumulated a great deal of clinical observation over two millennia, some of which produced results — the artemisinin story under traditional herbalism came out of exactly this literature.

We cannot say the theory and the practice stand or fall together, and this is the section's governing point. Needling produces real physiological effects. Whether those effects have anything to do with channels is a separate question, and the evidence on it is examined next.

Further reading

• Paul U. Unschuld, Medicine in China: A History of Ideas (1985) — the standard history.
• Kim Taylor, Chinese Medicine in Early Communist China, 1945–1963 (2005) — on the modern standardisation.
• Donald Harper, Early Chinese Medical Literature (1998) — the Mawangdui manuscripts in translation.