Library

The compilation of Materia Medica began with Shennong, and subsequent generations produced various transmitted texts, reaching a state of great completeness with the *Bencao Gangmu* (Compendium of Materia Medica). However, due to the vast volume of these works, memorization was difficult. Consequently, those with superficial knowledge often relied on the *Yaoxing Fu* (Ode to Drug Properties), resulting in a focus on only a few aspects while missing hundreds, causing endless harm. It was not until newer books such as the *Beiyao* (Essential Preparations) circulated that the functions of materia medica became prominent again. Nevertheless, their organizational structure still classified items by categories such as plants, insects, and fish. Readers merely recognized the nature, flavor, and indications of drugs but often ignored the meridians they entered. This led to criticism of "punishing the innocent" (inappropriate treatment) and made it difficult to achieve the precise efficacy likened to a needle attracting a mustard seed.

My friend, Master Yao of Shanyin, named Lan with the courtesy name Yun, was an expert in the Legalist school of Shen Buhai and Han Feizi. After passing the Mingjing examination and awaiting appointment as a Guangwen official, I invited him to reside in my guesthouse when I took up my post in Jiangxi. Our friendship lasted nearly thirty years. When he treated minor ailments for me, he would casually select just a few herbs, yet the effects were as immediate as a drumbeat following a strike. When asked about his understanding of Qi-Huang medicine, he replied, "I do not claim to understand medical theory; I simply know which meridian each drug enters." In the spring of the Gengzi year, while acting as the magistrate of Yue Commandery, I obtained a manuscript copy of the *Bencao Fenjing* (Materia Medica Classified by Meridians) compiled by Master Yao. During my leisure time from official duties, I read through it. The work uses meridians as the main outline and drugs as the sub-items, allowing readers to clearly understand which flavors belong to which meridians, thereby preventing indiscriminate prescribing. Its benefit to medical practice is indeed significant. Therefore, I hurriedly had it printed to facilitate its widespread dissemination. Yao Wu was prone to illness since childhood; by middle age, his beard and hair had completely fallen out, leading him to style himself as Vimalakirti Monk. Now past sixty, his vitality remains undiminished, which is likely a clear demonstration of the efficacy of taking medication according to meridian guidelines.

1. The book first presents diagrams of the internal landscape and meridians for reference, enabling patients to identify the location of their ailment and thus determine which meridian is affected and which meridian-specific drugs are appropriate.
2. The order of the twelve meridians: starting with the Hand-Taiyin Lung Meridian, followed by the Hand-Yangming Large Intestine Meridian, Foot-Yangming Stomach Meridian, Foot-Taiyin Spleen Meridian, Hand-Shaoyin Heart Meridian, Hand-Taiyang Small Intestine Meridian, Foot-Taiyang Bladder Meridian, Foot-Shaoyin Kidney Meridian, Hand-Jueyin Pericardium Meridian, Hand-Shaoyang Sanjiao Meridian, Foot-Shaoyang Gallbladder Meridian, and ending with the Foot-Jueyin Liver Meridian. This compilation does not follow this sequence, primarily for ease of consultation.
3. This work uses meridians as the framework and drugs as the entries. It is impossible to list all plant, insect, and mineral substances within a single meridian section. Therefore, a general index lists all drugs, and...
4. For any drug entering multiple meridians, annotations are provided under each entry in the general index. Regarding its nature, flavor, and functions, details are restricted to the first meridian listed for that drug...
5. Drugs that do not follow meridian pathways are categorized separately under "Miscellaneous Items." Any drug not annotated with a specific meridian in the general index, or one that acts generally throughout the body, belongs to this category.
6. Drugs associated with a specific meridian are grouped together based on similarity. Since their functions vary, they are further subdivided into six categories: Tonifying (Bu), Harmonizing (He), Attacking/Purgative (Gong), Dispersing (San), Cold-natured (Han), and Heat-natured (Re), to facilitate similar classification. This allows readers to select medications by category conveniently.
7. Many drugs have multiple names. Listing them separately under each name would result in a scattered and disorganized text. Therefore, drugs with synonymous names are collected in a separate volume for easy reference...
8. Knowledge of drug incompatibilities—such as mutual fear (Wei), aversion (E), opposition (Fan), and taboo (Ji)—is essential for students of materia medica. However, ancient prescriptions often combined such drugs. Rigid adherence to these incompatibilities without flexibility can lead to stagnation. One should study ancient formulas to understand their rationale rather than holding rigid views (like gluing a tuning peg). Thus, this compilation does not extensively detail incompatibilities.
9. The drug names and characters used in this book follow contemporary popular usage. For example, Yiyiren (Coix Seed) is written as Miren, Eshi as Niubangzi, and [missing character] Shi as [missing character]. Such colloquialisms are acceptable and facilitate access for beginners.