Library

The yin and yang of heaven and earth, the wind, cold, summer heat, and dampness, as well as cold, warmth, deficiency, and excess—all cause disease according to the individual's constitutional qi. They induce illness according to the local and seasonal qi. Originally, they cannot be discussed in a uniform manner.

For instance, two people may suffer from the same disease, yet the pathways of contracting the disease and the manifestations of suffering from it differ. Even within one person, the same disease occurring at different times may involve different patterns of meridians and zang-fu organs.

The principles of life are subtle; the principles of geography are subtle; the principles of medicine are also subtle. As the saying goes, "A miss is as good as a mile," which indeed proves true. Such deviations are difficult to rectify, making it not easy to speak lightly of medicine.

The reason may lie in the imprecise identification of symptoms and the limitations of scholarly attainment. This is akin to going into battle: if preparation is insufficient, proficiency is lacking; without proficiency, success is unattainable.

Furthermore, diseases contracted by humans have internal and external causes, deficiency and excess, fire and cold, yin and yang. Some summer-heat and dampness conditions resemble deficiency; some deficiency conditions mimic wind pathogens. Therefore, physicians must carefully observe and distinguish these.

I served in a humble official capacity amidst worldly hardships. Lacking the power to save the world, I possessed the heart to save lives. Regardless of whether my ability matched my intent, my heart always sought to exert itself fully.

Occasionally discussing the state of society and human hearts with my friend Shen Yuezhi, we turned to discussing medicine through the lens of disease. He joyfully presented me with a manuscript titled *Bihua Yijing* (Pen Flower Medical Mirror).

As this was a handwritten copy, I read it carefully, fearing that time might cause me to forget its contents. Since such books can indeed benefit the world and save lives, why not share them with like-minded friends?

Thus, I suddenly decided to have it printed and published, informing my colleagues, hoping it would assist fellow physicians and not fail to honor Mr. Jiang's earnest dedication. This serves as the preface.

Prefaced respectfully by Zhong Chenglu of Gushu, Wanjiang, during the first ten days of the mid-winter month in the 14th year of the Daoguang reign.

The most variable thing under heaven is disease. The most refined art under heaven is medicine. To achieve ultimate refinement to exhaust the understanding of variability, even thousands of words would not suffice to elucidate its threads.

Since Qibo, Leigong, and Daiji, numerous famous masters have emerged, their discussions abundant and varied. Yet, when applied to the changing nature of clinical conditions, there are cases difficult to address by simply consulting diagrams or texts.

Who am I, Jiang Hantun, to dare claim that a few shallow words can fully expound upon these matters?

However, while disease is highly variable, its manifestations rely on physical signs. While medicine is highly refined, its practice relies on theoretical principles. By seeking principles through physical signs, one employs simplicity to manage complexity. Understanding this allows one to connect disparate aspects. There are indeed matters that thousands of words cannot fully cover, yet a few words can encompass entirely.

Since middle age, I have devoted myself to medical studies, traveling between Jiangsu and Zhejiang, deeply knowing its difficulties, and daring not rest content with my own inadequacies.

When I took office in eastern Guangdong, my studies gradually languished. Yet, I frequently observed local physicians who, like literary scholars focusing merely on structure, lacked clear theory and method. How could they wield the authority of saving lives?

Patients generally did not study medicine seriously, relying instead on spirits and ghosts for blessings. Even when occasionally consulting a physician, they silently endured errors, unaware of the cause. Truly, "abstaining from medication is best."

I longed to promote remedial methods but was hindered by official regulations. Now, having resigned to return to the mountains, I have summarized the essentials and engraved them into this volume.

May everyone obtain concise prescriptions. Upon encountering a symptom, one can naturally compare it with the condition, determine which zang or fu organ is involved, identify whether it is yin or yang, and ensure alignment with the true nature of exterior/interior, deficiency/excess, and cold/heat.

One can then identify if it is a disease of the heart, liver, spleen, stomach, lungs, or kidneys. Once the symptoms are thoroughly understood, the efficacy of the medicine will naturally be manifest. Compared to those who entrust their lives to blind practitioners or use themselves as targets for experimentation, the benefits and losses are clearly distinguishable.

Sincerely, I hope those with aspirations in medicine will study this volume diligently, take it as a guideline, and cross-reference it with the works of great masters. Thus, everything can be understood at a glance. It can be used near to serve parents and far to benefit the masses, offering slight assistance to living beings. This serves as the preface.

Autographed by Jiang Hantun of Gui'an, Zhejiang, during the first ten days of the early summer month in the 4th year of the Daoguang reign.