医可易言乎哉。在圣门曰小道，在史家曰方伎。顾所谓小道者，特视大学之道，位天地
育万物为小焉耳。神圣作之于前，贤哲述之于后。李唐而降，斯道浸微。非实有至精至神，
方可与斯之一境，胡为史册所载，代不数人，若仓公、扁鹊、华元化一流，则更无代兴而特
起。江氏艮庭有云∶孔子圣无不通，焉有不知医者。自牖执手，切其脉也，而孔子教人游艺，
如礼记疏所称夫子脉诀，卒未闻传之其人，岂真以方伎而贱之，盖其慎也。忆余幼时曾以春
温误服麻黄，致举室怔营。迨咸丰丙辰，以副车入赀为比部主事，留滞京邸，又以寒痢为医
投凉剂而误。更医复然，危状迭见。赖友人检方书鉴前弊而拯之，得以无虞。余于是始有志
于医。恒诣厂肆购书，置之几案，朝夕披览，虽至困甚，亦冀鬼神来告，不悟彻不已。久之
为人疗病，时或幸中，谬窃虚誉。然自甲子改官邑令，所宰晋祁皖舒，皆地当孔道，差务络
绎，又不用门丁一人，事无巨细，靡不亲裁，计束医书高阁者，凡十八年。洎壬午调任盱眙，
自分无治剧才，甫捧檄，即乞疾而归，戢影蓬门，无以遣日，则复取群籍，研求加邃。乃喟
然曰∶余向之于医，犹门外汉耳，今其或者可与入门矣。夫学问之道，不外致知力行两端医
，何独不然。致知之书，如素问、灵枢、本草经尚矣。而伤寒论、金匮要略，则又南阳先师
本致知以为力行之书，灵素本经，悉括其中。学人能即是而寝馈笃好之，积以岁月，真可引
伸触长，施用无穷，然而谈何易也。人知辨证之难，甚于辨药；孰知方之不效，由于不识证
者半，由于不识药者亦半。证识矣而药不当，非特不效，抑且贻害。窃怪古来注仲圣书者，
无虑数十百家，独于方解，鲜精确澄彻。其故在本草之学，自来多不深求。识本草如是，遂
视方义亦当如是。于古人因证施治之微旨，去而千里矣。读仲圣书而不先辨本草，犹航断港
绝潢而望至于海也。夫辨本草者，医学之始基，实致知之止境，圣人列明辨于学问思之后，
其功自非易致。谫劣如余，何足语此。然而遐轨勉蹑，乐岂辞疲，秉烛之明，岁有增益。
自戊戌春有六气感证要义之刻，嗣于药用有心得者，即征诸方；方义有见及者，并印以药。
弗明弗措，惟竭吾才。今又六更裘葛，取所着稽之，得药百二十八味，聊依纲目编次，厘为
四卷。大抵援据仲圣两书，而间附以他说他药，随手札记，殊无体例。余老矣，值时局之艰
虞，念儒冠之多误，是惟弓冶，可得蝉嫣。爰命孙儿智浚，录付剞劂，以垂来许，并问世焉。
若云臧否人物，以自表异，斯医工之故习，而非余之所敢蹈尔。
光绪三十年甲辰夏四月，鹿起山人周岩自叙于微尚室，时年七十有三。
医学之道，岂是轻易可以谈论的吗？在孔门弟子眼中，它被视为“小道”；在史学家眼中，它属于“方伎”（医卜星相等技艺）。然而，所谓“小道”，只是相对于“大学”（格物、致知、诚意、正心、修身、齐家、治国、平天下）那种定位天地、养育万物的宏大道理而言，显得微小罢了。上古神圣之人开创了这一道统，贤哲之人随后加以阐述。自李唐王朝以来，这一道统逐渐衰微。如果没有真正达到极其精妙、神妙的境界，就无法进入这一领域。为什么史书记载中，每一代能称道的医生寥寥无几？像仓公（淳于意）、扁鹊、华佗（字元化）这样的人物，更是没有代代涌现、特然崛起。江氏艮庭曾说：“孔子圣德无所不通，怎会有不懂医术的道理？”孔子从窗下握着子路的手，为他切脉，但孔子教导人学习六艺，至于《礼记》注疏中所提到的夫子脉诀，最终并未听说传授给特定的人。这难道真的是因为轻视医技而鄙薄它吗？不，这是因为孔子行事谨慎啊。
回忆我年幼时，曾因春温病误服麻黄，导致全家惊恐不安。等到咸丰丙辰年，我通过捐纳获得副车资格，担任比部主事，滞留京城寓所，又因寒痢被医生投以凉剂而误治。更换其他医生也是如此，危险状况接连出现。幸得友人检阅药方，鉴察前人的弊端并拯救了我，才得以平安无事。我从此才开始立志学医。常常前往书肆购书，放在案头，早晚翻阅研读，即使困顿至极，也期望能得到鬼神启示，不到彻底领悟绝不罢休。久而久之，开始为人治病，有时侥幸治愈，窃取了虚名。然而自从甲子年改任县令，我所治理的晋祁、皖舒等地，都处于交通要道，差役事务络绎不绝，而且我不使用一个门丁，事情无论大小，无不亲自裁决，束之高阁的医书，总共长达十八年。等到壬午年调任盱眙，我自认为没有处理繁剧政务的才能，刚接到任命文书，就借口生病辞职回家，隐居柴门，无处打发时日，于是重新取出各类典籍，深入研究，更加精深。于是感叹道：“我过去对于医学，还像个门外汉，现在或许可以算是入门了。”
学问之道，不外乎“致知”（获取知识）和“力行”（实践行动）两个方面，医学难道唯独不是这样吗？获取知识的书籍，如《素问》、《灵枢》、《神农本草经》已经很高深了。而《伤寒论》、《金匮要略》，则是张仲景先师基于获取知识而写成的实践之书，《灵枢》、《素问》、《本经》的内容都囊括其中。学者如果能据此日夜沉浸、笃爱钻研，积累岁月，确实可以引申触类旁通，应用无穷，但这谈何容易！人们知道辨证之难，甚于辨药；谁又知道方剂不生效，一半是因为不认识证候，另一半是因为不认识药物呢？认识了证候但用药不当，不仅无效，反而会造成危害。我私下奇怪，自古以来注释仲景著作的，不少于数十百家，唯独对方剂的解释，很少有精确透彻的。原因在于本草之学，向来很少有人深入探究。认识本草如此，看待方义也就应当如此。对于古人因证施治的精微旨意，便相差千里了。读仲景的书而不先辨别本草，就像航行在断港绝潢之中却希望到达大海一样。
辨别本草，是医学的基础，也是获取知识的终极目标。圣人将“明辨”列在“学问思”之后，其功效自然不是轻易能达到的。像我这样浅薄低劣的人，哪里配谈论这些。然而，努力追随古人的足迹，快乐岂会推辞疲惫？秉烛夜读的明智，每年都有增益。自从戊戌春刊刻《六气感证要义》之后，凡是用药有心得的，就从方剂中征引验证；对方义有见解的，也结合药物印证书证。不明白就不放弃，只竭尽我的才华。到现在又过了六个寒暑，取我所著进行核查，得到药物一百二十八味，姑且依照《本草纲目》的体例编排，分为四卷。大体上援引依据仲景的两部著作，偶尔附上其他学说和其他药物，随手札记，完全没有固定的体例。我老了，正值时局艰难忧虑，想到儒生多误事，只有继承家业（指医学），可以得到延续。于是命令孙子智浚，抄录交付刻印，以流传后世，并向世人展示。如果说评论人物以显示自己与众不同，那是医工们的旧习，不是我敢效仿的。
光绪三十年甲辰夏四月，鹿起山人周岩在微尚室自叙，当时年龄七十三岁。
Is the Way of Medicine something that can be spoken of lightly? In the Confucian school, it is called a "minor art" (Xiao Dao); in the eyes of historians, it belongs to "technical skills" (Fang Ji). However, what is meant by "minor art" is merely small compared to the "Great Learning" (Da Xue)—the way of positioning heaven and earth and nurturing all things. The sages established it in the past, and the virtuous and wise expounded it afterwards. Since the Tang Dynasty, this Way has gradually declined. One cannot enter this realm unless one possesses true essence and spiritual profundity. Why is it that historical records show only a few individuals per generation? Figures such as Cang Gong (Chunyu Yi), Bian Que, and Hua Yuanhua (Hua Tuo) are even more rare, with no successive generations rising specifically. Jiang Genting said: "Confucius, being sage and universally competent, how could he not know medicine?" When Confucius held Zi Lu's hand through the window to take his pulse, yet when Confucius taught people to master the Six Arts, the "Master's Pulse Manual" mentioned in the commentary on the *Book of Rites* was never heard to have been transmitted to anyone. Was it truly because he despised technical skills? No, it was due to his caution.
I recall that in my childhood, I mistakenly took *Ephedrae Herba* (Mahuang, 麻黄) for Spring-Warmth disease, causing panic throughout my household. Later, in the Bingchen year of the Xianfeng era, having purchased the qualification of Vice-Chariot to become a Principal Secretary in the Ministry of Justice, I stayed in the capital. Suffering from cold-dysentery, I was wrongly treated by a physician who administered cooling agents. Subsequent physicians did the same, and critical conditions appeared repeatedly. Fortunately, a friend examined the prescriptions, identified the previous errors, and saved me, allowing me to remain safe. From then on, I began to resolve to study medicine. I frequently visited bookshops to purchase texts, placing them on my desk to read morning and night. Even when extremely exhausted, I hoped for divine revelation, ceasing only upon complete comprehension. Over time, I began treating others, occasionally succeeding by luck and stealing empty reputations. However, after changing office to County Magistrate in the Jiazi year, where I governed Jin-Qi and Wan-Shu—areas at major thoroughfares with continuous official duties—and without employing any gatekeepers, I personally handled every matter, large or small. Medical books were shelved away for eighteen years. When transferred to Xuyi in the Renwu year, believing myself lacking talent for complex administration, I immediately requested leave upon receiving the appointment and returned home. Hiding behind a humble door, with nothing to pass the days, I resumed studying various classics, deepening my research. I sighed and said: "My previous understanding of medicine was that of an outsider; now perhaps I may be considered to have entered the door."
The path of learning consists of nothing but "acquiring knowledge" (Zhi Zhi) and "practicing earnestly" (Li Xing); why should medicine be different? Books for acquiring knowledge, such as the *Suwen*, *Lingshu*, and *Shennong Bencao Jing*, are already profound. Yet the *Shanghan Lun* and *Jingui Yaolue* are works of practice written by Master Zhang Zhongjing based on acquired knowledge, encompassing the contents of the *Lingshu*, *Suwen*, and *Bencao Jing*. If scholars can immerse themselves in these texts with sincere devotion over years, they can indeed extend their understanding and apply it infinitely, though this is easier said than done. People know that distinguishing syndromes (Bian Zheng) is harder than distinguishing herbs; who knows that half the ineffectiveness of prescriptions stems from not recognizing syndromes, and the other half from not recognizing herbs? Even if the syndrome is recognized, inappropriate medication not only fails to work but also causes harm. I privately wonder why, among the dozens of commentaries on Master Zhongjing's works throughout history, few provide precise and clear explanations of formulas. The reason lies in the fact that the study of Materia Medica has rarely been deeply sought. Recognizing Materia Medica thus leads to viewing formula principles similarly. This distances one from the subtle purport of ancient physicians' treatment according to syndromes by thousands of miles. Reading Master Zhongjing's books without first distinguishing Materia Medica is like sailing in a dry canal and hoping to reach the sea.
Distinguishing Materia Medica is the foundation of medicine and the ultimate goal of acquiring knowledge. The Sages placed "clear discrimination" after "study, inquiry, and reflection," and its merit is certainly not easily achieved. How can someone as shallow and inferior as I discuss this? Nevertheless, striving to follow in the footsteps of the ancients, does joy not preclude fatigue? The light of holding a candle adds yearly. Since the spring of Wuxu, when *Six Qi Sensation Evidence Essentials* was printed, whenever I had insights into herb usage, I verified them through formulas; whenever I had insights into formula principles, I corroborated them with herbs. I do not stop until clarity is achieved, exhausting my talents. Now, six cycles of winter coats and summer clothes have passed. Reviewing my writings, I have collected 128 herbs. Tentatively arranging them according to the outline of the *Bencao Gangmu*, I have divided them into four volumes. Generally relying on the two books of Master Zhongjing, occasionally attaching other theories and herbs, these are random notes without strict format. I am old, facing difficult times, thinking of how many scholars have erred; only by inheriting the family craft can continuity be maintained. Thus, I ordered my grandson Zhi Jun to copy and submit for printing, to transmit to future generations and present to the world. If it involves judging figures to distinguish myself, that is the old habit of medical artisans, which I dare not imitate.
In the fourth month of summer, Jiachen year of the Guangxu 30th year, Zhou Yan, known as Lushan Mountain Man, wrote this preface in Weishang Studio, aged seventy-three.