余读仲景之叙医，辄为之掩卷，盖其感生死之芒忽，笃君父之危殆。贱名利之浮荣，冀
年寿以没世。伤哉其言，焉得不原本药性，加意候诊者乎？三皇御宇，太昊首书八卦，开万
世道术之祖。而神农遍尝百味，黄帝着为《素问》，迹其鼎足，所化医之用居多。今考本经
所载草木鸟兽等类，则干木果震萑苇坤子母牛兑羊良狗之说，酸咸有五味之别，青黄有五色
之分。则坎水离火震木兑金坤土之说，定浮沉，明燥湿。则本天本地亲上亲下之说，立君臣，
分佐使。则君一民二之说，有畏有喜，有恶有反。则吉凶利害之说，有补有泻，有正治，有
从治。则变通趋时之说，无非大易之源流，八卦之分布。圣人所以顺风气而防夭札者，端不
越此。自太史公着《扁仓论》，以为美好者不祥之器。而儒者又好自张大，置医于九流之中。
欲如皇子之论当心，东里之辩六气，文挚止疾于齐王，枚乘霍然于太子，岂可得哉。余以少
孤，不及掺药以进慈父，间为母氏尝之，退而考诸方书，多所不合。斯用痛心，乃于读书之
暇，发本经仙经暨十四家本草四子等书，靡不悉究。然后辨阴阳之所属，五行之所宜，着《
药性解》二卷。敢谓拯危济殆，于是焉赖，特以志余之悲，为人子事亲之一助尔。且夫甘旨
以养之，温清以奉之。而卒罹夫不可疗之灾，欲代则不能，欲遍访而证诸人则不及，此人子
终天之恨。仲景氏伤之，余所不辞而为之缕析者也。若夫《素问》一书，轩岐之精蕴在焉，
亦欲订其同异而折衷之。期于剖微而止，敬以异日，公之同好。
云间李中梓撰
When I read Zhang Zhongjing's preface on medicine, I am often moved to close the book. This is because he laments the subtle distinction between life and death, and deeply worries about the critical danger facing rulers and fathers. He disdains the fleeting glory of fame and wealth, hoping only for longevity until his natural end. The sorrow in his words—how could one fail to trace back to the original nature of medicinal substances and pay close attention to pulse diagnosis?
During the reign of the Three Sovereigns, Taihao (Fuxi) first inscribed the Eight Trigrams, initiating the ancestor of Daoist arts for ten thousand generations. Meanwhile, Shennong tasted hundreds of flavors, and Huangdi composed the *Suwen* (Yellow Emperor's Classic of Internal Medicine). Tracing their tripod-like contributions, the transformation of medical utility accounted for the majority. Now, examining the categories of herbs, trees, birds, and beasts recorded in the *Benjing* (*Shennong Bencao Jing*), there are theories such as "dry wood and fruits belong to Zhen, reeds and rushes to Kun, mother cow to Dui, good dog to..." [Note: Text implies correspondence], distinguishing sour and salty among the Five Flavors, and green and yellow among the Five Colors. Thus, the theory of Kan Water, Li Fire, Zhen Wood, Dui Metal, and Kun Earth establishes floating and sinking properties, clarifying dryness and dampness. Based on the principles of "originating from Heaven and Earth, adhering to upper and lower," the roles of Monarch (Jun), Minister (Chen), Assistant (Zuo), and Guide (Shi) are established. Following the "One Monarch, Two Ministers" concept, relationships of fear, joy, aversion, and reversal among drugs are defined. According to theories of auspiciousness, inauspiciousness, benefit, and harm, tonification and purgation, as well as direct and contrary treatments, are determined. These principles of adaptation and timing are nothing but the source flow of the Great Yi (*I Ching*) and the distribution of the Eight Trigrams. The sages' method of following wind patterns to prevent pestilence and premature death indeed does not transcend these principles.
Since Grand Historian Sima Qian wrote the *Bian Cang Lun*, asserting that beautiful things are often vessels of ill omen, Confucian scholars have tended to exaggerate themselves, placing physicians among the Nine Schools of Thought. Is it possible to achieve results like the Prince discussing the heart's position, Dongli debating the Six Qi, Wenzhi curing disease at the King of Qi's court, or Mei Cheng instantly healing the Crown Prince? Such feats are hardly attainable.
Having lost my father at a young age, I was unable to offer medicinal remedies to my loving father. Occasionally, I tested medicines for my mother, but upon consulting medical texts later, I found many discrepancies. This caused me deep pain. Therefore, during my leisure from reading, I thoroughly investigated the *Benjing*, immortal classics, fourteen families of Materia Medica, and works by the Four Masters, leaving no stone unturned. Thereafter, I distinguished the affiliations of Yin and Yang, and the suitability of the Five Elements, composing the two volumes of *Yaoxing Jie* (Explanation of Drug Properties). I dare not claim that rescuing the critically ill relies solely on this work; rather, it serves to express my grief and act as a modest aid for children serving their parents. Moreover, providing sweet foods for nourishment and offering warmth in winter and coolness in summer are duties of filial piety. Yet, if one ultimately suffers an incurable disaster, being unable to take the suffering oneself, nor having time to consult all experts to verify symptoms, this becomes a lifelong regret for any child. Zhang Zhongjing grieved over this, so I do not decline to analyze and explain these matters in detail. As for the *Suwen*, it contains the profound essence of Xuanyuan (Huangdi) and Qibo. I also intend to correct its similarities and differences and reach a compromise. I hope to dissect the subtle details and stop there, respectfully reserving this for future sharing with those who share my interests.
Written by Li Zhongzi from Yunjian