Ao Shi Shang Han Jin Jing Lu — The World’s Earliest Monograph on Tongue Diagnosis

As early as the oracle bone inscriptions of the Shang Dynasty in China, there are records of “zhen ji she” (divining about diseases of the tongue), which already implied the diagnosis of pathological tongue conditions. In the Neijing (Yellow Emperor’s Inner Classic), compiled around the 3rd–5th centuries BCE, there are already numerous records concerning tongue diagnosis. For example, regarding the color of tongue coating, it held that yellow tongue coating indicated internal heat. There was also “tongue curling,” referring to the tongue curling inward and unable to protrude, which was considered to be due to high fever and clouded spirit. The Nan Jing (Classic of Difficult Issues) also contains some records on tongue diagnosis. By the Han and Tang periods, Zhang Zhongjing coined the term “she tai” (tongue coating) and established tongue diagnosis as a basis for pattern differentiation and treatment. Later, books such as Zhu Bing Yuan Hou Lun, Zhong Zang Jing, Qian Jin Fang, and Wai Tai Mi Yao also mentioned some content on tongue diagnosis. By the Song, Jin, and Yuan periods, Huo Ren Shu used the presence or absence of dry mouth and tongue to differentiate yin-yang and deficiency-excess, and Xiao Er Yao Zheng Zhi Jue first proposed the names “protruded tongue” (shu she) and “playing tongue” (nong she). However, the tongue diagnosis content recorded in the above literature was relatively scattered. The earliest work in China specifically devoted to tongue diagnosis must be Ao Shi Shang Han Jin Jing Lu, which is also the world’s earliest monograph on tongue diagnosis.

In the 13th century (Yuan Dynasty), a person surnamed Ao conducted detailed research on tongue diagnosis and carefully summarized the clinical experience of tongue inspection and pattern differentiation at that time, completing the book Ao Shi Shang Han Jin Jing Lu. The main content of this book discusses tongue diagnosis in cold damage. In this book, he arranged various tongue images, drew 12 charts, and discussed symptoms through tongue diagnosis.

After the completion of Ao Shi Shang Han Jin Jing Lu, due to the limitations of the time, it did not circulate widely, and today the original version can no longer be seen. Fortunately, a man named Du Qingbi discovered this book, personally drew 24 tongue image charts, combined them with the original 12 to make 36, and had them printed and published in 1341 CE. However, because the print run was small, few people saw the book.

The version of Ao Shi Shang Han Jin Jing Lu we see today is the edition supplemented by Du Qingbi. The book focuses on cold damage but also covers some internal medicine and other diseases. It mainly uses tongue color to distinguish cold and heat, deficiency and excess, and internal damage versus external contraction, and records the treatment and formulas for the diseases indicated by each tongue color. The entire book is divided into 36 tongue colors, each with an attached diagram. This has certain guiding significance for clinical application.

In the Ming Dynasty, the famous physician Xue Ji incorporated Du Qingbi’s supplemented Ao Shi Shang Han Jin Jing Lu verbatim into his Xue Shi Yi An (Xue’s Medical Records), which allowed it to circulate widely. Xue Ji commented on the book as follows: “In the past there was a book called Ao Shi Jin Jing Lu that specifically used tongue color to diagnose disorders. The book not only illustrated the conditions of various tongue colors but also wrote in detail the diseases indicated by each tongue color, and then separately recorded their formulas and medicinals. A physician need only turn to this book to see everything clearly and distinctly. Although it cannot compare with Zhang Zhongjing’s writings, it is very much in line with Zhang Zhongjing’s principles. It is truly both profound and accessible, both practical and concise.”

Later, a man named Shen Douyuan wrote Guan She Xin Fa, increasing the tongue diagnosis charts to 137. After that, a man named Zhang Danxian wrote Shang Han She Jian, changing the number to 120. However, from the perspective of actual clinical needs, correctly identifying 36 types of tongue coating is sufficient to meet ordinary clinical requirements. Therefore, the value of Ao Shi Shang Han Jin Jing Lu is actually greater than books such as Guan She Xin Fa and Shang Han She Jian.

The author of Ao Shi Shang Han Jin Jing Lu was an unsung hero. Today, apart from knowing his surname was Ao, nothing is recorded about his given name, background, or place of origin. The survival of this earliest monograph on tongue diagnosis in China depended on Du Qingbi’s revision in the Yuan Dynasty and Xue Ji’s inclusion in the Ming Dynasty. In ancient times, writing a book was certainly not easy, but ensuring its transmission was even more difficult.

TCM tongue diagnosis has also exerted a considerable influence on Western medicine. Western diagnostics has gradually come to emphasize changes in the tongue body, tongue coating, and tongue mobility. For example, in patients with hyperthyroidism, the tongue often trembles when protruded; in acromegaly and myxedema, the tongue body is enlarged; in hypochromic anemia, the tongue surface is smooth; in riboflavin deficiency, irregular elevations may appear on the tongue epithelium; and in scarlet fever, the tongue is bright red and shaped like a strawberry. These correspond with the TCM diagnostic principle that diseases of the important viscera can be reflected on the tongue, and that tongue diagnosis can be used to understand the patient’s condition, changes, and outcome. Precisely because TCM tongue diagnosis is important, many countries around the world are conducting in-depth research. Through tongue fluorescence examination, tongue printing, pathological sections of the tongue, in vivo microscopy of the tongue, tongue scraping smears, and various physiological, biochemical, and hemorheological measurements, they are exploring the mysteries of tongue diagnosis, allowing the ancient TCM tongue diagnosis to make even greater contributions to world medicine.