无不偏之药，则无统治之方。如方书内所云∶某方统治四时不正之气，甚至有兼治内伤产妇者。
皆不通之论也。近日方书盛行者，莫过汪 庵《医方集解》一书，其中此类甚多，以其书文理颇
通，世多读之而不知其非也。天下有一方而可以统治四时者乎？宜春者即不宜夏，宜春夏者更不宜
秋冬。余一生体认物情，只有五谷作饭。可以统治四时饿病，其他未之闻也。在五谷中尚有偏胜，最
中和者莫过饮食，且有冬日饮汤，夏日饮水之别。况于药乎！得天地五运六气之全者，莫如人，人之
本源虽一，而人之气质，其偏胜为何如者？人之中最中和者，莫如圣人，而圣人之中，且有偏于任，偏
于清，偏于和之异。千古以来不偏者，数人而已。常人则各有其偏，如《灵枢》所载阴阳五等可知也。
降人一等，禽与兽也；降禽兽一等，木也；降木一等，草也；降草一等，金与石也；用药治病者，用偏
以矫其偏。以药之偏胜太过，故有宜用，有宜避者，合病情者用之，不合者避之而已。无好尚，无
畏忌，惟病是从。医者性情中正和平，然后可以用药，自不犯偏于寒热温凉一家之固执，而亦无笼统
治病之弊矣。
古来着本草者，皆逐论其气味性情，未尝总论夫形体之大纲，生长化收藏之运用，兹特补之。盖
芦主生，干与枝叶主长，花主化，子主收，根主藏，木也；草则收藏皆在子。凡干皆升，芦胜于干；凡
叶皆散，花胜于叶；凡枝皆走络，须胜于枝；凡根皆降，子胜于根；由芦之升而长而化而收，子则复降
而升而化而收矣。此草木各得一太极之理也。
愚之学，实不足以着书，是编之作，补苴罅漏而已。末附二卷，解儿难、解产难，简之又简，
只摘其吃紧大端，与近时流弊，约略言之耳。览者谅之。
没有哪味药是完全没有偏性的，因此也就没有能统管所有疾病的方剂。比如医书中常说：某个方子可以统御四季不正之气（外感病邪），甚至有说兼治内伤和产妇疾病的。这都是不通达的言论。近来流行的医书，没有超过汪昂的《医方集解》这一本的，其中这类说法很多，因为这本书文理比较通顺，世人多读它而不知道它是错误的。天下有哪一个方子可以统管四季疾病吗？适合春季使用的就不适合夏季，适合春夏使用的更不适合秋冬。我一生体察事物的情态，只有五谷做饭可以统管四季的饥饿之病，其他的我没听说过。在五谷之中尚有偏性，最中和的莫过于饮食，而且还有冬天喝热汤、夏天喝凉水的区别。何况是药物呢！得天地五运六气全备的，没有人能比得上人，人的本源虽然一致，但人的气质禀赋，其偏性又是怎样的呢？人中最中和的，莫过于圣人，而圣人之中，也有偏于任（承担）、偏于清（清静）、偏于和（平和）的差异。千古以来没有偏性的，屈指可数罢了。普通人则各有偏性，如《灵枢》所载阴阳五等分类就可以知道。再降一等，是禽类和兽类；再降禽兽一等，是树木；再降树木一等，是草类；再降草类一等，是金属与石头。用药治病，是用药物的偏性来纠正人体的偏性。因为药物的偏性太过，所以有的适宜使用，有的应当避开，符合病情的就使用，不符合的就避开罢了。没有个人的喜好崇尚，没有畏惧忌讳，只以病情为从。医者性情中正平和，然后才能用药，自然不犯偏执于寒、热、温、凉某一家的固执毛病，也没有笼统治病的弊端了。
自古以来撰写本草著作的人，都是逐一论述药物的气味和性情，未曾总体论述形体的大纲、生长化收藏的运用规律，这里特意加以补充。大概芦（根茎上部）主生发，干（主干）与枝叶主生长，花主化育，子（果实/种子）主收敛，根主闭藏，这是木的特性；草类则是收藏都在子中。凡是干都主升，芦胜过干；凡是叶都主发散，花胜过叶；凡是枝都主走窜经络，须（根须）胜过枝；凡是根都主沉降，子胜过根；由芦的升发而至生长、化育、收敛，子则又复归沉降、升发、化育、收敛。这就是草木各得一太极的道理。
我的学问实在不足以著书，这部书的编写，只是为了修补遗漏和不足而已。末尾附上两卷，解释儿科难症、产科难症，内容极其简略，只摘取其中最关键的大端，与近时的流弊，大致说明一下罢了。希望读者体谅。
There is no medicine without bias, therefore there is no single prescription that can govern all diseases. For instance, medical texts often claim: "This prescription governs the pathogenic factors of abnormal qi in all four seasons," or even that it treats both internal injury and postpartum conditions. These are all untenable arguments. Among the medical books popular in recent times, none surpasses Wang Ang's *Yi Fang Ji Jie* (Collection of Medical Prescriptions). It contains many such statements. Because its literary style is quite fluent, people read it widely without realizing its errors. Is there any single prescription in the world that can govern diseases across all four seasons? What is suitable for spring is not suitable for summer; what is suitable for spring and summer is even less suitable for autumn and winter. Throughout my life, observing the nature of things, I have found only that grain cooked into rice can govern the disease of hunger in all four seasons; I have never heard of anything else doing so. Even within grains, there are biases. The most balanced entity is diet itself, which still distinguishes between drinking hot soup in winter and cold water in summer. How much more so with medicines! Among all things, humans possess the complete influence of the Five Movements and Six Qi (Wuyun Liuqi) from Heaven and Earth. Although human origin is one, human temperament and constitution vary greatly in their biases. Among humans, the sages are the most balanced, yet even among sages, there are differences: some lean towards bearing responsibility (Ren), some towards clarity/purity (Qing), and some towards harmony (He). Since ancient times, those without bias have been few and far between. Ordinary people each have their own biases, as indicated by the classification of Yin and Yang into five grades recorded in the *Ling Shu* (Spiritual Pivot). Descending one level, we have birds and beasts; descending one level from birds and beasts, we have trees; descending one level from trees, we have herbs/grasses; descending one level from herbs, we have metals and stones. In treating diseases with medicine, one uses the bias of the medicine to correct the bias of the body. Because the bias of medicines is excessive, some are suitable for use while others should be avoided. One uses what matches the condition and avoids what does not. There should be no personal preference or fear/taboo; one follows only the disease. A physician must have a balanced and peaceful temperament before using medicine. Only then can one avoid the rigidity of sticking exclusively to cold, heat, warm, or cool therapies, and also avoid the drawback of treating diseases in a generalized manner.
Throughout history, authors of Materia Medica have discussed the flavor, nature, and temperament of substances individually, but have rarely summarized the general outline of their physical forms or the dynamics of growth, transformation, accumulation, and storage. Here, I specifically supplement this. Generally, the rhizome stem (Lu) governs birth/growth, the trunk and branches/leaves govern elongation/growth, flowers govern transformation/maturation, seeds/fruits govern gathering/storage, and roots govern hiding/storage; this applies to trees. For herbs, gathering and storage are contained within the seed. Generally, trunks ascend; the rhizome stem ascends more than the trunk. Generally, leaves disperse; flowers disperse more than leaves. Generally, branches move through collaterals; root hairs move more than branches. Generally, roots descend; seeds descend more than roots. From the ascending of the rhizome stem to growth, transformation, and gathering, the seed then again descends, ascends, transforms, and gathers. This is the principle that each plant and herb possesses its own Taiji (Supreme Ultimate).
My learning is truly insufficient for writing books. The purpose of this compilation is merely to patch up omissions and gaps. At the end, I append two volumes explaining difficulties in pediatrics and obstetrics. They are simplified to the utmost, extracting only the most critical major points and briefly discussing contemporary malpractices. I ask readers to understand this.