今所用之膏药，古人谓之薄贴。其用大端有二∶一以治表，一以治里。治表者，如呼脓
去腐
，止痛生肌，并摭风护肉之类。其膏宜轻薄而日换，此理人所易知；治里者，或驱风寒，或
和气血，或消痰痞，或壮筋骨，其方甚多，药亦随病加减。其膏宜重浓而久贴，此理人所难
知，何也？盖人之疾病，由外以入内，其流行于经络脏腑者，必服药乃能驱之。若其病既有
定所，在于皮肤筋骨之间，可按而得者，用膏贴之，闭塞其气，使药性从毛孔而入其腠理，
通经贯络，或提而出之，或攻而散之，较之服药尤有力，此至妙之法也。故凡病之气聚血结
而有形者，薄贴之法为良。但制膏之法，取药必真，心志必诚，火候必至，方能有效，否则
不能奏功。至于敷熨吊 种种杂法，义亦相同，在善医者通变之而已。
古圣人之立方，不过四五味而目。其审药性，至精至当；其察病情，至真至确。方中所
用之
药，必准对其病，而无毫发之差，无一味泛用之药，且能以一药兼治数症，故其药味虽少，
而无症不该。后世之人，果能审其人之病，与古方所治之病无少异，则全用古方治之，无不
立效。其如天下之风气各殊，人之气禀各异，则不得不根据古人所制主病之方，略为增减，则
药味增矣。又或病同而症甚杂，未免欲兼顾，则随症增一二味，而药又增矣。故后世之方，
药味增多，非其好为杂乱也。乃学不如古人，不能以一药该数症，故变简而为繁耳。此犹不
失周详之意。且古方之设，原有加减之法，病症杂出，亦有多品之剂，药味至十余种。自唐
以后之方，用药渐多，皆此义也。乃近世之医，动云效法汉方，药止四五味，其四五鼓掌之
药，有用浮泛轻淡之品者，虽不中病，犹无大害。若趋时之辈，竟以人参、附子、干姜、苍
术、鹿茸、熟地等峻补辛热之品，不论伤寒、暑湿，惟此数种轮流转换，以成一方，种种与
病相反，每试必杀人，毫不自悔，既不辨病，又不审药性，更不记方书，以为此乃汉人之法
。呜呼！今之所学汉人之方，何其害人如此之毒也！其端起于近日之时医，好为高论以欺人；
又人情乐于温补，而富贵之家尤甚。不如是则道不行，所以人争效尤，以致贻害不息。安有
读书考古，深思体验之君子，出而挽回之，亦世道生民之大幸也！
现在所使用的膏药，古人称之为薄贴。它的主要用途有两方面：一是治疗体表疾病，二是治疗体内疾病。治疗体表疾病的，如呼出脓液、去除腐肉、止痛生肌，以及防风护肉之类的作用。这类膏药应当轻薄并每日更换，这个道理人们容易理解；治疗体内疾病的，有的驱散风寒，有的调和气血，有的消除痰饮痞块，有的强壮筋骨，方剂很多，药物也随病情加减变化。这类膏药应当厚重浓稠且长时间贴敷，这个道理人们难以知晓，为什么呢？因为人的疾病，由外部侵入内部，那些流行于经络脏腑间的病邪，必须通过服药才能驱除。如果病邪已有固定位置，位于皮肤筋骨之间，可以触摸查得的，使用膏药贴敷，闭塞毛孔之气，使药性从毛孔进入腠理，贯通经络，或者将其提出体外，或者攻逐消散，比服药更有力量，这是极其精妙的治疗方法。所以凡是病气聚集、血行凝结而有形质的病症，薄贴的方法是好的。但是制作膏药的方法，取药必须纯正，心意必须真诚，火候必须到位，才能见效，否则不能奏效。至于敷熨吊等各种杂法，道理也是相同的，在于善于治病的医生灵活变通罢了。
古代圣人制定方剂，不过四五味药而已。他们审视药性，极其精准恰当；他们考察病情，极其真实确切。方中所用的药，必定准确对应病情，没有毫发之差，没有一味泛泛使用的药，而且能以一味药兼治多种症状，所以虽然药味少，但没有不涵盖的症状。后世之人，如果能仔细审察病人的病，与古方所治疗的病没有丝毫差异，那么完全使用古方治疗，没有不立即见效的。无奈天下各地风气各不相同，人的体质禀赋各异，则不得不根据古人所制定的主治疾病的方子，略微增减，那么药味就增加了。又或者病情相同但症状复杂，难免想要兼顾，于是随症状增加一二味药，药味又增加了。所以后世的方剂，药味增多，不是他们喜欢杂乱无章。而是学问不如古人，不能用一味药概括多种症状，所以将简单的变为复杂的。这还不失周详的意思。况且古方的设立，原本就有加减的方法，病症杂出，也有多味药的方剂，药味多达十余种。自唐代以后的方剂，用药逐渐增多，都是这个意思。然而近世的医生，动不动就说效法汉代方剂，药只四五味，那四五味鼓掌之药（注：此处原文“鼓掌”疑为衍文或误植，结合语境指随意搭配的药物），有用浮泛轻淡药物的，虽然不对症，还无大害。若是趋炎附势之辈，竟用人参、附子、干姜、苍术、鹿茸、熟地黄等峻补辛热的药物，不论伤寒、暑湿，只是这几种轮流转换，组成一方，种种与病情相反，每次尝试必致人死亡，毫不后悔，既不辨别病情，又不审视药性，更不记忆方书，认为这是汉代人的方法。唉！现在所学汉人的方剂，害人竟然如此毒辣！其起因始于近日的时间医生，喜欢发表高论来欺骗人；加上人情乐于接受温补疗法，而富贵人家尤其严重。如果不这样做道就不能推行，所以人们争相效仿，以致危害不停息。怎么会有读书考古、深思体验的君子出来挽回这种局面，这也是世间百姓的大幸啊！
The plasters currently in use were called "bo tie" (thin patches) by the ancients. Their primary applications are twofold: one is for treating exterior conditions, and the other for interior conditions. For treating exterior conditions, such as promoting pus discharge, removing necrotic tissue, relieving pain, generating flesh, and protecting muscles from wind exposure, the plaster should be thin and light, replaced daily; this principle is easily understood by people. For treating interior conditions, such as expelling wind-cold, harmonizing qi and blood, resolving phlegm and palpable masses, or strengthening sinews and bones, there are many formulas, and the herbs are added or subtracted according to the disease. The plaster for these purposes should be thick and heavy, applied for a long duration; this principle is difficult for people to understand. Why? Because diseases in humans enter from the exterior into the interior. Pathogens circulating in the meridians and zang-fu organs must be expelled through oral medication. However, if the pathogen has a fixed location, situated between the skin, sinews, and bones, and can be palpated, applying a plaster seals the pores' qi, allowing the medicinal properties to enter the cou-li (subcutaneous tissue) through the hair follicles, penetrate the meridians and collaterals, either extract the pathogen out or attack and disperse it. This is more effective than oral medication and is an extremely ingenious method. Therefore, for any condition where qi stagnation and blood stasis have formed a tangible mass, the bo tie method is beneficial. However, the method of preparing plasters requires authentic herbs, sincere intention, and precise control of fire heat to be effective; otherwise, it will not work. As for various miscellaneous methods such as poultices, hot compresses, and hanging treatments, the principle is the same, relying on the skilled physician's ability to adapt flexibly.
The ancient sages formulated prescriptions with merely four or five herbs. Their examination of herb properties was extremely precise and appropriate; their observation of disease conditions was extremely true and accurate. The herbs used in the prescription precisely matched the disease without the slightest deviation, with no casually used herbs, and each herb could treat multiple symptoms simultaneously. Thus, although the number of herbs was small, no symptom was left uncovered. If later generations could carefully examine the patient's condition and find it identical to that treated by ancient prescriptions, using the complete ancient prescription would yield immediate results. Unfortunately, climatic conditions vary across regions, and individual constitutional endowments differ. Consequently, physicians had to slightly modify the main disease-formulas created by the ancients, thereby increasing the number of herbs. Furthermore, when diseases were similar but symptoms complex, physicians attempted to address all symptoms, adding one or two herbs, further increasing the count. Thus, the increase in herbal ingredients in later prescriptions was not due to a preference for complexity, but because their learning did not match that of the ancients; they could not cover multiple symptoms with a single herb, transforming simplicity into complexity. This still retained a sense of thoroughness. Moreover, ancient prescriptions originally included methods for modification; when symptoms were mixed, multi-herb formulations existed, sometimes reaching over ten herbs. Since the Tang Dynasty, the number of herbs in prescriptions gradually increased, following this logic. However, modern physicians often claim to emulate Han dynasty prescriptions, limiting them to four or five herbs. These few herbs may include superficial and mild substances; although ineffective, they cause little harm. Yet, opportunistic practitioners use potent warming and tonifying herbs like Renshen (Ginseng Radix), Fuzi (Aconiti Lateralis Radix Praeparata), Ganjiang (Zingiberis Rhizoma), Cangzhu (Atractylodis Rhizoma), Lurong (Cervi Cornu Degelatinatum), and Shudihuang (Rehmanniae Radix Praeparata). Regardless of whether the condition is Shanghan (Cold Damage) or Summerheat-Dampness, they rotate only these few herbs to form a prescription. Such approaches contradict the disease, often leading to death upon trial, yet they show no remorse, failing to differentiate the disease, assess herb properties, or recall classical texts, falsely claiming this is the Han method. Alas! How toxic is the harm caused by those who now study Han prescriptions! This trend originated from contemporary fashionable physicians who use lofty theories to deceive people; compounded by the public's preference for warming and tonifying therapies, especially among the wealthy. Without such practices, their "Dao" cannot prevail, so people imitate them, causing endless harm. Would it not be a great fortune for the world and its people if scholars who read classics, research antiquity, and deeply reflect could emerge to reverse this situation?