The Classic of Difficult Issues
With commentaries by Chinese and Japanese authors
from the third through the twentieth century
translated and annotated by
Paul U. Unschuld
The Contents of the Nan-ching
An innovative diagnostic approach and a coherent concept of needling therapy are, on first glance, the
two central messages conveyed by the Nan-ching; they represent, however, but two ingredients of a
virtually complete conceptual system of medical care that also includes a detailed discussion of
physiology, etiology, and pathology.
As is the case with the editions of the Su-wen and the Ling-shu that are extant, the textus receptus of
the Nan-ching consists of eighty-one sections. In the Su-wen, all eighty-one sections are designated
by a specific topic to which is added consistently the term lun ("discussion" or simply "on..."); in the
Ling-shu, only a fraction of the eighty-one section titles carries the adjunct lun, while the majority
have only the topic discussed as their title. In the Nan-ching, in contrast, all eighty-one sections are
merely called nan, and they are numbered consecutively with no topics appearing as titles. The term
nan has been interpreted by Eastern and Western authors in various ways. Hsü Ta-ch’un, an eminent
eighteenth century author of conservative medical writings and a commentator on the Nan-ching, read
nan as "question-and-answer dialogue" or "examination." He concluded: "The aim [of the Nan-ching]
is to explain difficult issues in the text of the classic. Hence it poses questions concerning these
difficult issues (wen-nan) and, then, clarifies them. Therefore it is called Nan-ching.”15 Okanishi
Tameto, the late Japanese historian of Chinese medical literature, followed Hsü Ta-ch'un here when
he identified nan as wen-nan,16 and so, most recently, did Ku Wei-ch'eng, the editor of San-pai
chung i-chi lu.17
The following is a survey of the contents of each of the eighty-one difficult issues grouped in six chapters.
CHAPTER ONE: THE MOVEMENT IN THE VESSELS AND ITS DIAGNOSTIC
The first difficult issue
Explanation of the significance of the "inch-opening" for diagnosing illnesses through investigating
the movement in the vessels.
The second difficult issue
Introduction of the first subdivision of the inch-opening into an "inch-section" and a "foot-section,"
divided by a line called "gate."
The third difficult issue
Discussion of the terms "great excess," "insufficiency," "mutual takeover by yin and yang,"
"turnover," "overflow," "closure," and "resistance" as diagnostic parameters indicated by specific
movements in the vessels.
The fourth difficult issue
Explanation of yin and yang patterns of movement in the vessels, and introduction of the concept of
three longitudinal levels in the movement in the vessels.
The fifth difficult issue
Introduction of the concept of five longitudinal levels in the movement in the vessels, and of a method
to distinguish these levels.
The sixth difficult issue
Discussion of the terms "yin abundance, yang depletion" and "yang abundance, yin depletion" as
diagnostic parameters indicated by specific movements in the vessels.
The seventh difficult issue
Explanation of the significance of the appearance of any of the three yin and three yang kinds of
movement in the vessels as they are related to the six periods within one year.
The eighth difficult issue
Explanation of the significance of the "moving influences" (also called "vital influences") in the
organism, as appearing at the inch-opening.
The ninth difficult issue
How to distinguish illnesses in the depots and palaces by the speed of the movement in the vessels.
The tenth difficult issue
Introduction of the concept of "ten variations" in the movement in the vessels, as can be felt in the
different sections at the wrist that are associated with specific depots.
The eleventh difficult issue
Explanation of the concept that one depot is void of influences if the movement in the vessels stops
once in less than fifty arrivals.
The twelfth difficult issue
Introduction of the concept that the internal or external parts of the organism may be cut off from the
movement in the vessels.
The thirteenth difficult issue
Introduction of the concept of a correspondence between a person's complexion, the movement in the
vessels as felt at the inch-opening, and the condition of the skin in the foot-section of the lower arm.
The fourteenth difficult issue
Introduction of the concepts of "injured" (i.e., slower than usual) and "arriving" (i.e., faster than
usual) movements in the vessels; also, discussion of the significance of the presence of a movement
in the vessels at the inch-section when no movement can be perceived at the foot-section, and vice
The fifteenth difficult issue
Elucidation of the changes in the movements in the vessels in accordance with the passing of the four
The sixteenth difficult issue
Discussion of various methods to diagnose illnesses by taking internal and external evidence into
The seventeenth difficult issue
How to predict a patient's impending death or survival by comparing the movement in his vessels
with other manifestations of his illness.
The eighteenth difficult issue
Systematized presentation of the correspondences of the yin and yang conduits with the inch-, gate-,
and foot-sections near the wrist where the movement in the vessels can be felt, on the basis of the
mutual generation order of the Five Phases. Also, discussion of methods for recognizing internal
accumulations and chronic illnesses through the movement in the vessels.
The nineteenth difficult issue
Introduction of the concept of differences in the movement in the vessels in males and females.
The twentieth difficult issue
Introduction of the concepts of hidden and concealed movements in the vessels, of doubled
influences and of lost influences.
The twenty-first difficult issue
On the prognostic significance of situations where a patient's bodily appearance shows signs of
illness while the movement in his vessels does not, and vice versa.
The twenty-second difficult issue
Elaboration of the concepts of illnesses in the vessels that are "excited" and of those that are
CHAPTER TWO: THE CONDUITS AND THE NETWORK-VESSELS
The twenty-third difficult issue
Systematized presentation of the lengths and courses of the conduit vessels as sections of a large
circulatory system. Also, reference to the significance of feeling the movement in the vessels at the
wrists of both hands, and explanation of the concepts of "end" and "beginning."
The twenty-fourth difficult issue
Systematized presentation and prognostic evaluation of external symptoms indicating that a specific
conduit-vessel has been cut off from the movement in the vessels.
The twenty-fifth difficult issue
Explanation of the concept of "twelve conduits" in the presence of only five depots and six palaces
through the introduction of the concepts of "heart-enclosing network" and "Triple Burner" as carrying
a name (i.e., fulfilling a function) without having a form (i.e., an anatomical substratum).
The twenty-sixth difficult issue
Remarks on the fifteen network-vessels.
The twenty-seventh difficult issue
Introduction of the term "eight single-conduit vessels," and of the concept that they function as
"ditches and reservoirs" absorbing surplus contents of the main conduits.
The twenty-eighth difficult issue
Description of the courses of the eight single-conduit vessels in the organism.
The twenty-ninth difficult issue
List of signs and symptoms caused by illnesses in the eight single-conduit vessels.
CHAPTER THREE: THE DEPOTS AND THE PALACES
The thirtieth difficult issue
Elucidation of the concepts of constructive and protective influences, and introduction of the idea that
the depots and palaces are supplied with influences by the stomach directly.
The thirty-first difficult issue
Innovative reinterpretation of the concept of the Triple Burner as a functional description of the upper,
central, and lower groups of organs in the body.
The thirty-second difficult issue
Explanation of why the heart and the lung are the only depots located above the diaphragm.
The thirty-third difficult issue
Discussion of apparent contradictions resulting from the association of the liver and lung with the
phases wood and metal, respectively.
The thirty-fourth difficult issue
Pattern of the five depots and their corresponding sounds, complexions, odors, liquids, and tastes.
Association of the five depots with the seven spirits.
The thirty-fifth difficult issue
Discussion of theoretical issues concerning the functions and locations of the six palaces, especially
as they are related to the five depots.
The thirty-sixth difficult issue
Introduction of the concept that the organism has two kidneys, one of them constituting the "gate of
The thirty-seventh difficult issue
Elucidation of the concept that the influences of the five depots pass through specific orifices, thus
maintaining the functions of these orifices. Also, further discussion of the concepts of closure and
resistance, and reference to the concepts of turnover and overflow.
The thirty-eighth difficult issue
Further elucidation of the nature and function of the Triple Burner as an answer to the question of
why there are six palaces but only five depots in the body.
The thirty-ninth difficult issue
Further elucidation of the nature and function of the gate of life and of the Triple Burner in reference
to the existence of six palaces but only five depots.
The fortieth difficult issue
Discussion of apparent contradictions resulting from the association of the nose with the lung (which
is responsible for the sounds, while the nose is responsible for distinguishing the odors) and from the
association of the ears with the kidneys (which are responsible for the liquids, while the ears are
responsible for distinguishing the sounds).
The forty-first difficult issue
Explanation of why the liver is the only depot that has two lobes.
The forty-second difficult issue
Description of all depots and palaces in terms of length, diameter, weight, and capacity.
The forty-third difficult issue
Explanation of the phenomenon that someone who does not eat or drink will die after seven days.
The forty-fourth difficult issue
List of the names and locations of the seven through-gates.
The forty-fifth difficult issue
Introduction of the concept of the eight gathering-points.
The forty-sixth difficult issue
On different sleeping patterns in old and young people.
The forty-seventh difficult issue
Why the face can stand cold.
CHAPTER FOUR: ON ILLNESSES
The forty-eighth difficult issue
Introduction of various diagnostic patterns allowing one to distinguish whether a person suffers from
a depletion or from a repletion.
The forty-ninth difficult issue
Introduction of the concepts of primary affection by the five evil influences from outside the
organism, and of secondary affection by evil influences transmitted within the organism.
The fiftieth difficult issue
Introduction of the concepts of "depletion evil," "repletion evil," "destroyer evil," "weakness evil,"
and "regular evil," denoting the five possibilities of internal secondary affliction.
The fifty-first difficult issue
Explanation of different preferences and aversions on the side of the patient permitting one to
distinguish whether an illness is located in the depots or palaces.
The fifty-second difficult issue
On the static nature of illnesses in the depots and on the mobile nature of illnesses in the palaces.
The fifty-third difficult issue
Introduction of the concepts of "transmission of an illness through seven depots" and of
"transmission skipping a depot."
The fifty-fourth difficult issue
Illnesses in the depots are difficult to cure; illnesses in the palaces are easy to cure.
The fifty-fifth difficult issue
Reinterpretation of the concepts of "accumulation" and "concentration" illnesses.
The fifty-sixth difficult issue
Reinterpretation of terms and concepts related to accumulation illnesses, and introduction of a
systematic theory of the generation of the five accumulation illnesses.
The fifty-seventh difficult issue
Introduction of a five-fold classification of different diarrheas.
The fifty-eighth difficult issue
Introduction of a five-fold classification of "harm caused by cold" illnesses and of the different
movements in the vessels resulting from these illnesses. Also, a list of signs and symptoms allowing
for a diagnosis of illnesses caused by heat and cold.
The fifty-ninth difficult issue
How to distinguish falling sickness from madness.
The sixtieth difficult issue
Discussion of the concepts of "stagnant pain" and "true pain" in head and heart.
The sixty-first difficult issue
Introduction of a categorization of healers as "spirits'" "sages," "artisans," and "workmen," based on
their respective approaches to diagnosing an illness.
CHAPTER FIVE: TRANSPORTATION HOLES
The sixty-second difficult issue
Explanation of why the conduits associated with the palaces have six transportation holes, while
those associated with the depots have only five.
The sixty-third difficult issue
Explanation of why each conduit has a "well" as its first transportation hole.
The sixty-fourth difficult issue
Introduction of a systematic categorization of the transportation holes according to yin and yang and
the Five Phases.
The sixty-fifth difficult issue
Remarks concerning the "well" and "confluence" transportation holes.
The sixty-sixth difficult issue
Discussion of the "origin" transportation holes as outlets of the "original influences" of the six depots
and six palaces.
The sixty-seventh difficult issue
Explanation of the location of "concentration holes" on the front and of "accumulation holes" on the
back of one's body.
The sixty-eighth difficult issue
Introduction of a list of illnesses that can be cured by needling the respective transportation holes
associated with them.
CHAPTER SIX: NEEDLING PATTERNS
The sixty-ninth difficult issue
General advice on how to fill a depletion and drain a repletion, and when to remove an illness from an
affected conduit itself.
The seventieth difficult issue
Introduction of a pattern of two different needling techniques to be applied during the spring-summer
and autumn-winter seasons, respectively.
The seventy-first difficult issue
Advice for needling the constructive and the protective influences.
The seventy-second difficult issue
Reinterpretation of the terms "moving against" and "following" as concepts referring to the direction
of the movement in the vessels.
The seventy-third difficult issue
Advice to needle a "brook" transportation hole if theory requires needling a "well" hole.
The seventy-fourth difficult issue
Introduction of a pattern of needling different holes in the course of the five seasons.
The seventy-fifth difficult issue
Elucidation of the theoretical basis underlying the therapeutic approach of filling a so-called depletion
and of draining a so-called repletion.
The seventy-sixth difficult issue
Discussion of the concepts of "filling" and "draining."
The seventy-seventh difficult issue
Introduction of a classification of healers as "superior" or "mediocre" practitioners according to their
understanding of the transmission of illnesses within the organism.
The seventy-eighth difficult issue
Reinterpretation of the techniques of filling and draining by means of needling.
The seventy-ninth difficult issue
Further elucidation of the theoretical basis underlying the treatment of states of depletion and
The eightieth difficult issue
Comments on the techniques of inserting and withdrawing a needle.
The eighty-first difficult issue
Warning against "replenishing a repletion" and "depleting a depletion."
1. Nan Jing