Library

The principle of Taiji (Supreme Ultimate) is fully encompassed by Yin and Yang. Their movement and stillness serve as mutual roots; thus, the Yin within Yang and the Yang within Yin are also fully encompassed.

The Yin and Yang of Heaven and Earth must necessarily disperse into the Five Phases (Wu Xing). This is what is meant by "form resides on Earth, Qi circulates in Heaven," leaving nothing out, thereby rendering it inexhaustible within the Six Directions (the universe). Consequently, is it not from this that humans derive their Zang-Fu organs, Qi and Blood, Ying (Nutritive Qi), and Wei (Defensive Qi)? Similarly, is it not from this that plants, insects, fish, birds, beasts, metals, stones, water, and earth derive their properties of warmth, coolness, cold, heat, dryness, dampness, ascending, and descending?

Although Yin and Yang are relatively easy to distinguish, the concepts of "Yin within Yang" and "Yang within Yin" are subtle and difficult to articulate. Even Shennong and the Yellow Emperor, with their divine sagacity, relied on tasting herbs, inner vision, and the use of needles, stones, and bi (stone lancets) to probe their boundaries and examine their meridians before they could grasp these principles. How absurd, then, are the rash actions of mediocre practitioners and arrogant fools! To thoroughly examine the Yin within Yang and the Yang within Yin, one must observe all things, understanding that while all things share a single Taiji, each thing possesses its own Taiji. By knowing that human nature corresponds with the Four Seasons, and that drug properties correspond with the Zang-Fu organs, we realize that the underlying principle is identical.

Human nature corresponds with the Four Seasons, and drug properties correspond with the Zang-Fu organs, because both acquire form by inheriting the Qi of Heaven and Earth, and their natures are inherent within them. Thus, although movement and stillness are opposite, they serve as mutual roots; although Yin and Yang are distinct, they serve as mutual dwellings. This is what is meant by: "The Five Phases are but Yin and Yang; Yin and Yang are but Taiji; Taiji is but Wuji (Non-Limit)." This represents the unity of the One amidst the Many. The Great Creation has its root in the transformation of Qi, yet the generation of humans and all living beings does not transcend this. For humans, the Taiji of Yin and Yang is complete, housing the Zang-Fu organs; for other things, the Yin and Yang of Taiji are divided into Qi and Flavor. This is the One dispersing into the Many. Tracing back to the One establishes the Substance (Ti), wherein the functions of the Many are fully present; dispersing into the Many activates the Functions (Yong), while the Substance of the One remains intact.

Sages such as Xuanyuan (Yellow Emperor) and Qibo possessed innate knowledge of this. Later sages like Zhang Jiegou, Li Dongyuan, Wang Haizang, and Zhu Danxi elucidated and clarified it. They had divinely illuminated the subtle and ineffable mysteries of the harmonious blending of Pre-Heaven and Post-Heaven energies. Mediocre practitioners fail to perceive this, and authors often select imprecisely or describe vaguely. It is indeed arduous to explore the interplay of Yin and Yang to regulate the fluctuations of fullness and emptiness. This is precisely why Mr. Liu Yunmi, Grand Coordinator of Qianjiang, authored *Bencao Shu* (Compendium of Materia Medica Descriptions).

Mr. Liu passed the Jinshi examination in the Yichou year of the Tianqi era. He began his career as a county magistrate, served as a supervising official, resigned in protest against contemporary trends, and gained renown for his upright integrity. At the end of the Chongzhen reign, he was recommended again. He later traveled through the Fujian and Zhejiang coastal regions. Seeing the decline of central authority and realizing that the situation was hopeless, he firmly requested retirement at an age dedicated to studying the *I Ching* (Book of Changes). He styled himself "Liyuan Yisou" (Recluse of Li Garden) and lived in seclusion, writing for thirty years, paying special attention to this work. His heart was set on benefiting all beings, but since he could not achieve this through political action, he embedded his aspirations in this book. With profound learning and exquisite insight, he was able to discern the inherent natures of materia medica, penetrate the mysteries of Yin and Yang, and grasp the origin of harmonious transformation. The compilation collected formulas and theories from various schools, weighing and comparing them. Even works revered as canonical, such as Li Shizhen’s *Bencao Gangmu* (Compendium of Materia Medica), were subject to selection and omission. Truly, there is nothing more to add.

His son, Liu Chun, Magistrate of Lianshui, governed for three years with effective administration and social harmony, sparing the people from premature death and epidemics. He derived significant benefit from his family's scholarly heritage and wished to enable the common people to attain benevolence and longevity. He entrusted me with proofreading and publishing the book. My younger brother, Yan Yang, who served as an educational official in this region, assisted in correcting the text, leading to its completion. This is a benevolent art. Mr. Liu harbored the wish of Fan Zhongyan to be both a capable minister and a skilled physician. However, unlike Fan Zhongyan, he did not achieve fame through political merit but instead devoted his passion to medical texts. This was likely due to the constraints of his times. Readers of this book in later generations may understand the context of its author.

On the Tianshuang Festival in the sixth month of summer, in the Ji Mao year of the Kangxi reign, Gao You, a junior scholar from Jiaxing, respectfully wrote this preface.