What kind of Way is medicine? It is said: It is the Way of the Junzi (gentleman/noble person). If one does not possess a steadfast mind, how can they lightly discuss it! Why is this? The nature of drugs can both give life and take life. If handled without grasping the essentials, what was meant to save life becomes a means of taking it. Only the Junzi acts thus; their heart is not frivolous, therefore their practice must be refined. When facing illness, they examine with thoroughness and caution, thus transforming grief into joy. The nature of the Xiaoren (petty person) is cruel and greedy; greed leads them to seek only profit, cruelty leads them to slight and disregard human life. When facing illness, they boast and act hastily, failing to investigate whether the disease is excess or deficiency, and rashly administer drastic medicines that induce severe reactions. To avoid killing the patient would be rare. I firmly adhere to the Way of the Junzi. In my later years, I had a son who had just passed his weak crown age (20 years old); he was frail and prone to illness, lazy by habit and unable to strive for self-improvement. He certainly is not one capable of bearing this Way. I grieve day and night, fearing that after my death, illnesses will be entrusted to mediocre physicians, which can harm life and destroy nature. Mencius said: "There are three forms of unfilial conduct, of which having no descendants is the greatest." Having a son who is often ill, yet not transmitting to him the Way of saving lives, so that he might die young and the ancestral sacrifices be cut off—how could this be the way of a father? I am now seventy-seven years old, extremely aged and feeble. My twilight years, how long can they shine? Day and night, I have devoted myself to compiling the *Shanghan Mingli Xubian* (Continued Compilation of Clarifying Principles in Cold Damage). Although the discussions and methods are roughly complete, without oral transmission from a master, one cannot fully integrate and comprehend them in the heart. I also composed a volume titled *Suoyan* (Trivial Words). Although the text is humble and vernacular, the language is concise and the meaning reaches its point. It includes the untransmitted subtleties of Zhang Zhongjing, all unheard of in the world. I bare my heart and liver to exhaust the profound mysteries, truly providing a ladder to ascend high. You should treasure it like pearls and jade, devote yourself to studying and interpreting it, searching to fully grasp its purport. Ask whenever you have doubts; do not procrastinate. Strive earnestly to advance daily toward higher realms. Sima Guang said, "If successful, become a good prime minister; if not, become a good physician." Is this not the Way of the Junzi? You should hold this teaching firmly in your heart, practice it with reverence and caution. In the future, if you can use this Way to benefit others, you too will be a Junzi. But if your mind does not resemble that of the ancients, regarding my words as absurd and erroneous, and instead using this Way to kill people, thereby betraying my intentions, you are not my son.
Written by Tao Hua, Daoist Ren Jie of Yuhang, on the Zhongyuan Day of the Yichou Year of the Zhengtong Era (1445 AD)