予尝谓造化者，万物之司命；君人者，三才之司命；典校者，文章之司命；将帅者，三军之司
命；而医也者，又自天子以至庶人者之司命也。其所关系岂浅鲜哉？故先儒有云∶不明五运六气，
检遍方书何济；不明十二经络，开口动手便错。而孙思邈亦曰∶不明阴阳者，不足谓之太医旨哉
斯言，诚业是业者所当深切究心者也。予独怪今时之医，始无见理之明，终无应变之巧。务奇诡
者，或远慕而近遗∶局方书者，或举一而废百。此虚实损益之间，不免毫厘千里之谬，而医之祸
人不为少矣。 其然者，则考索未精，体玩未熟，与闻见之未广耳。新安徐东皋氏，潜心斯道者，
殆三十年，其活人不可以千万计。尝谓予曰∶医之精髓奥窍，《内经》一书备之。嗣是人殊代异，
门径虽多，要不能出乎此。譬诸峙者皆山，而泰岳则其宗也；流者皆水，而沧溟则其元也。然自
非综博千古，参伍诸家，旁搜曲证，又乌知《内经》有兼总条贯之妙耶？此《医统》之编所以不
容已也。予取而读之，见其条分缕析，随论折衷，如纲之在网，如领之在裘，俾学子一举而免颠
倒紊乱之弊，题之曰《古今医统》。是真能会百家之异同，接轩岐之正脉，虽谓此书之外无医可
也。昔仲尼簇圣之大成，朱子集诸儒之大成，若徐君亦可谓集医家之大成矣所以登斯世斯民于
春台寿域之中，厥功固不伟欤！虽然，下学可以言传，上达必由心悟徐君以明医重京师，齐驱襄
扁，奴仆刘张，无险夷难易，随试而辄效者，则运用之妙，存乎一心，而《医统》又其绪余也。
是在学人之自得焉耳。知言者以为何如？
钦差提督漕运镇守淮安地方总兵官太子太保灵璧侯古濠汤世隆撰
我曾说过，天地造化是万物的主宰；君主是天地人三才的主宰；掌管校勘的人是文章的主宰；将帅是三军的主宰；而医生，则是从天子到平民百姓的主宰。其所承担的关系难道不重大吗？所以先前的儒者说：如果不明白五运六气，即使翻遍方书又有什么用呢；如果不明白十二经络，一开口动手就会出错。孙思邈也说：如果不明白阴阳，就不配称为太医。这些话真是精辟啊，这确实是从事这一职业的人应当深入钻研的。
我唯独奇怪现在的医生，起初没有洞察事理的明智，最终没有随机应变的技巧。追求奇诡怪异的，往往远慕古法而近遗实用；拘泥于《局方》书籍的，往往举其一端而废弃其他。在虚实补泻之间，不免产生毫厘之差、千里之谬的错误，而医生祸害人的情况也不少了。造成这种情况的原因，则是考察探索不够精密，体悟玩味不够熟练，以及见闻不够广博罢了。
新安徐东皋先生，潜心于医学之道，大概三十年了，他救活的人不可胜数。他曾对我说：医学的精髓奥窍，《内经》一书已经完备了。此后人们不同、时代各异，门径虽然很多，但终究不能超出这个范围。这就好比耸立的都是山，而泰山是它们的宗主；流动的都是水，而沧海是它们的源头。然而如果不是综合博览千古，参互考证各家学说，广泛搜集曲折证明，又怎么知道《内经》有兼总条贯的美妙之处呢？这就是编写《医统》这本书之所以不容拖延的原因。
我拿来阅读它，看到它条理分明、分析细致，随着论述进行折衷取舍，就像纲绳在网中一样（提纲挈领），就像衣领在皮衣上一样（执本末从），使学习者一举避免颠倒混乱的弊病，题名叫做《古今医统》。这真是能汇聚百家异同，承接黄帝岐伯的正统血脉，甚至可以说除了这本书之外就没有别的医学了。从前孔子集圣人之大成，朱熹集众儒之大成，像徐君也可以说是集医家之大成了。因此把世人百姓置于春台寿域之中，他的功劳确实伟大啊！
虽然如此，下层的学问可以通过言语传授，高深的道理必须通过内心领悟。徐君以精通医学闻名于京城，与古代名医扁鹊、秦越人并驾齐驱，视刘涓子、张仲景为奴仆（意指超越他们），无论险阻平坦、困难容易，每次尝试都能见效，这是因为运用的妙处在于一心，而《医统》只是他余力的展现罢了。这在于学习者的自我领悟罢了。懂行的人认为怎么样呢？
钦差提督漕运镇守淮安地方总兵官太子太保灵璧侯古濠汤世隆撰写
I have often said that the creative forces of nature are the masters of all things; the ruler is the master of the Three Powers (Heaven, Earth, and Humanity); the official in charge of textual verification is the master of literature; the general is the master of the three armies; and medicine, furthermore, is the master of everyone from the Son of Heaven down to the common people. Is not the relationship involved here profound? Therefore, former Confucian scholars stated: "If one does not understand the Five Movements and Six Qi (Wuyun Liuqi), what use is it to search through all medical books? If one does not understand the Twelve Meridians, every opening of the mouth and movement of the hand will be erroneous." Sun Simiao also said: "One who does not understand Yin and Yang cannot be called a Grand Physician." These words are truly insightful; they are indeed matters that those engaged in this profession should study with deep concentration.
I alone find it strange that contemporary physicians lack clarity in perceiving principles at the outset and possess no skill in adapting to changes by the end. Those pursuing bizarre and unconventional methods may admire ancient theories while neglecting practical applications; those confined to the *Ju Fang* (Formulary) texts may cite one aspect while discarding hundreds of others. In the balance between deficiency and excess, and in the application of tonification and purgation, errors of a hair's breadth can lead to deviations of a thousand li, causing significant harm to patients. The reasons for this are that their investigation is not precise, their embodiment and practice are not mature, and their knowledge and experience are not extensive enough.
Mr. Xu Donggao of Xin'an has devoted himself to this path for nearly thirty years, saving countless lives. He once told me: "The essence and profound secrets of medicine are fully contained in the *Neijing* (Inner Canon). Since then, individuals have differed and eras have changed; although there are many schools and paths, none can ultimately transcend this foundation. It is like how all towering forms are mountains, yet Mount Tai is their patriarch; all flowing forms are water, yet the vast ocean is their source. However, unless one comprehensively surveys antiquity, cross-references various schools, and searches widely for corroborating evidence, how could one know the excellence of the *Neijing* in integrating and organizing all threads? This is why the compilation of the *Yitong* (Medical Unity) was indispensable."
Upon reading it, I found its structure clear and analysis detailed, with arguments balanced according to context. It acts like the cord in a net or the collar on a fur coat, allowing students to avoid confusion and disorder in a single step. Thus titled *Gujin Yitong* (Comprehensive Medical Unity through the Ages), it truly synthesizes the similarities and differences of a hundred schools and continues the orthodox lineage of Huangdi and Qibo. One might even say that outside of this book, there is no other medicine. Just as Confucius synthesized the greatness of the sages, and Zhu Xi synthesized the greatness of the Confucian scholars, Mr. Xu can be said to have synthesized the greatness of physicians. Thus, his merit in elevating the world and its people to an era of spring-like peace and longevity is indeed magnificent!
Nevertheless, lower learning can be transmitted through words, but higher understanding must be realized through the mind. Mr. Xu gained fame in the capital for his mastery of medicine, rivaling Bian Que and Qin Yueren, surpassing Liu Juanzi and Zhang Zhongjing, achieving efficacy regardless of difficulty or ease, because the subtlety of application lies within the heart. The *Yitong* is merely a byproduct of this mastery. This depends on the self-realization of the learner. What do those who understand speech think of this?
Written by Tang Shilong, Marquis of Lingbi, Grand Tutor to the Crown Prince, General Officer Guarding Huai'an, and Commissioner-in-Chief of Grain Transport under Imperial Commission.