读前人之书，当知其立言之意。苟读其书，而不知其意，求适于用，不可得也。豆疮之论，钱氏为详，历举源流经
络，明分表里虚实，开陈其施治之法，而又证以论辩之言，深得着书垂教之体。学人读而用之，如求方圆于规矩，较平
直于准绳，引而伸之，触类而长之，可为无穷之应用也。今人不知致病之因，不求立方之意，仓卒之际，据证检方，漫
尔一试，设有不应，并其书而废之，不思之甚也。近因《局方》之教久行，《素问》之学不讲，抱疾谈医者，类皆喜温而
恶寒，喜补而恶解利。忽得陈氏方论，皆燥热补剂，其辞确，其文简，欢然用之，翕然信之，遂以为钱氏不及陈氏远矣。
或曰∶子以陈氏方为不足欤？曰∶陈氏方诚一偏论，虽然亦可谓善求病情者，其意大率归重于太阴一经。盖以手太阴属
肺，主皮毛也；足太阴属脾，主肌肉。肺金恶寒而易于感，脾胃土恶湿而无物不受，观其用丁香、官桂，所以治肺之寒
也；用附、术、半夏，所以治脾之湿也。使其肺果有寒，脾果有湿而兼有虚也。量而与之，中病即止，何伤之有？今也
不然，徒见其疮之出迟者，身热者，泄泻者，惊悸者，气急者，渴思饮者。不问寒热虚实，率投木香散、异功散，间有
偶中，随手获效。设或误投，祸不旋 。何者？古人用药制方，有向导，有监制，有反佐，有因用。若钱氏方固未尝废
细辛、丁香、白术、参、 等，率有监制辅佐之药，不专务于温补耳！然其用凉寒者多，而于辅助一法，略开端绪，未
曾深及。痴人之前，不可说梦，钱氏之虑至矣，亦将以候达者扩充推展而用。虽然渴者用温药，痒塌者用补药，自陈氏
发之，迥出前辈。然其多用桂、附、丁香等燥热，恐未为适中也。何者？桂、附、丁香辈，当有寒而虚，固是的当，虚
而未必寒者。其为害当何如耶？陈氏立方之时，必有挟寒而豆疮者，其用燥热补之固其宜也。今未挟寒而用一偏之方，
宁不过于热乎？予尝会诸家之粹，求其意而用之，实未敢据其成方也。试举一二以证之。
从子六七岁时患痘疮，发热，微渴，自利。一小方脉视之，用木香散，每帖又增丁香十粒。予切疑焉。观其出迟，
固因自利而气弱。察其所下，皆臭滞陈积，因肠胃热蒸而下也。恐非有寒而虚，遂急止之，已投一帖矣。继以黄连解毒
汤加白术，与十帖以解丁香之热，利止疮亦出。其后肌常有微热，而手足生痈疖，与凉剂调补逾月而安。
又一男子，年十六、七岁，发热而昏，目无视，耳无闻，两手脉皆豁大而略数，知其为劳伤矣。时里中多发痘者，
虽不知人，与药则饮，与粥则食。遂教参、 、当归、白术、陈皮大料浓煎与之，饮至三十余帖痘始出，又二十余帖，
则成脓泡，身无全肤。或曰∶病势可畏，何不用陈氏全方治之？余曰∶此但虚耳，无寒也。只守前方，又数十余帖而安。
后询其病因，谓先四、五日恐有出痘之病，遂极力樵采，连日出汗甚多，若用陈氏全方，宁无后悔？
至正甲申春，阳气早动，正月间，邑间痘疮不越一家，卒投陈氏方，童幼死者百余人。虽由天数，吾恐人事亦或未
之尽也。
阅读前人的著作，应当了解他们立论的意图。如果只读书而不理解其用意，想要在实际应用中得当，是不可能的。关于痘疮（天花）的论述，钱乙（钱氏）最为详尽，他历数了疾病的源头、经过和经络，明确区分了表里虚实，陈述了治疗的方法，并用辩论性的语言加以论证，深得著书立说、垂教后人的规范。学习者读了并加以运用，就像用圆规和矩尺来求方圆，用准绳来比较平直一样，引申开来，触类旁通，可以产生无穷的应用价值。
现在的人不知道致病的原因，不探究处方背后的用意，在紧急关头，根据症状翻找药方，随意尝试一下，如果病情没有好转，就连同书籍一起废弃掉，这是非常缺乏思考的表现。近来因为《太平惠民和剂局方》（简称《局方》）的教导长期流行，《黄帝内经·素问》的学问不再被讲习，患有疾病谈论医术的人，大多喜欢温补而厌恶寒凉，喜欢补益而厌恶疏解通利。突然得到陈氏的方论，里面全是燥热补益的药剂，言辞确切，文字简练，于是高兴地使用它，一致地相信它，便认为钱乙不如陈氏相差甚远了。
有人问：“你认为陈氏的方子不足取吗？”回答说：“陈氏的方子确实是一种偏颇的理论，虽然如此，也可以说是善于探求病情的人，他的意图大体上归结重于太阴经（手太阴肺经和足太阴脾经）。因为手太阴属肺，主管皮毛；足太阴属脾，主管肌肉。肺金（肺气）厌恶寒冷且容易感受外邪，脾胃土（脾胃功能）厌恶湿气且无所不受。观察他使用丁香、官桂，是用来治疗肺的寒冷；使用附子、白术、半夏，是用来治疗脾的湿气。假如肺果真有寒，脾果真有湿并且兼有虚证，衡量程度后给予药物，中病即止（病情缓解就停药），有什么伤害呢？
现在却不是这样，仅仅看到那些痘疮发出迟缓的、身体发热的、腹泻的、惊悸的、气急的、口渴想喝水的患者，不问是寒证还是热证，实证还是虚证，一律投用木香散、异功散，偶尔有碰巧奏效的，随手获得效果。假如误用了，灾祸立刻就会发生。为什么呢？古人用药制方，有引导药（向导），有监制药，有反佐药，有因势利导的用法。像钱乙的方子固然未尝废弃细辛、丁香、白术、人参、甘草等，但通常都有监制和辅佐的药物，并不专门致力于温补！然而他使用凉性寒性药物的较多，而在辅助这一法度上，刚刚开了个头绪，未曾深入。对愚钝的人之前，不可说梦话，钱乙的考虑已经很周到了，也是等待通达之人去扩充推展而使用。
虽然口渴者用温药，瘙痒塌陷者用补药，是从陈氏开始提出的，远远超出前辈。但是他多用桂枝、附子、丁香等燥热药物，恐怕未必恰当。为什么呢？桂枝、附子、丁香这类药物，当患者确有寒证且虚时，固然是恰当的，但对于虚而未必有寒的情况，造成的危害该有多大呢？陈氏制定方子的时候，必定有夹杂寒邪的痘疮患者，他用燥热药物补益确实是适宜的。现在没有夹杂寒邪却使用这种偏颇的方子，难道不是过于温热了吗？我曾经综合各家的精华，探求其意旨而运用，实在不敢拘泥于现成的方子。试举一两个例子来证明这一点。
我的侄子六七岁时患痘疮，发热，轻微口渴，自行腹泻。一位小方脉医生诊视后，使用木香散，每帖又增加丁香十粒。我对此深表怀疑。观察他痘疮发出迟缓，固然因为自行腹泻导致气弱。检查他排泄物，都是臭秽滞涩的陈积之物，是因为肠胃热气蒸腾而下泄所致。恐怕不是有寒而虚，于是急忙停止用药，此时已经服用了一帖。接着使用黄连解毒汤加白术，给他服用了十帖以解除丁香的燥热，腹泻停止，痘疮也发出了。此后他的肌肤常有微热，手足生出痈疖，给予凉性药物调理补益，过了一个月才安定。
又有一个男子，年龄十六七岁，发热且神志昏沉，眼睛看不见，耳朵听不见，两手脉搏都豁大而略快，我知道这是劳伤所致。当时乡里多发痘疮，虽然他不省人事，给药则喝，给粥则吃。于是教他用人参、甘草、当归、白术、陈皮大剂量浓煎给他服用，喝了三十多帖痘疮才发出，又二十多帖，则形成脓泡，身上没有完好的皮肤。有人说：“病势可怕，为什么不用陈氏的全方来治疗？”我说：“这只是虚证，没有寒邪。只坚守前面的方子，又几十帖后才痊愈。后来询问病因，他说先四五天担心会有出痘的病，于是极力砍柴采集，连日出汗很多，如果用陈氏的全方，岂不是会留下后悔？”
至正甲申年春天，阳气发动较早，正月间，县里的痘疮不超过一家，突然投用陈氏的方子，童幼死者百余人。虽然由天数决定，但我恐怕人事方面也没有做到极致吧。
When reading the works of predecessors, one must understand their intent in establishing theories. If one reads the books without understanding their intent, it is impossible to apply them effectively in practice. Regarding the discussion on variola (smallpox), Qian Yi (Qian Shi) was the most detailed. He enumerated the origins, progression, and meridians of the disease, clearly distinguishing between exterior/interior and deficiency/excess, and expounded upon treatment methods, further substantiating them with argumentative discourse. This approach deeply embodies the standard of writing for instruction. For students who read and apply these works, it is like seeking squares and circles using a compass and set square, or judging straightness using a plumb line; by extending and applying this knowledge, one can achieve infinite applications.
People nowadays do not understand the causes of disease nor seek the rationale behind prescriptions. In emergencies, they consult formulas based on symptoms and try them indiscriminately. If the treatment fails, they discard both the formula and the book, which is extremely lacking in thought. Recently, due to the long-standing influence of the *Jufang* (Formulas of the Bureau of People's Welfare and Health) and the neglect of studies on the *Suwen* (Basic Questions of the Yellow Emperor's Inner Canon), those discussing medicine while ill tend to prefer warming and tonifying agents while rejecting cooling and resolving/discharging agents. Upon encountering Chen Shi's (Chen Yan's) formulas, which consist entirely of drying, hot, and tonifying preparations, characterized by precise language and concise text, they joyfully adopt and uniformly trust them, concluding that Qian Yi falls far short of Chen Shi.
Someone might ask: "Do you consider Chen Shi's formulas inadequate?" I reply: "Chen Shi's formulas indeed represent a biased theory. Nevertheless, he can be said to have been good at discerning the condition of the disease. His general intent focuses heavily on the Taiyin meridians (Hand-Taiyin Lung Meridian and Foot-Taiyin Spleen Meridian). The Hand-Taiyin belongs to the Lung, which governs the skin and hair; the Foot-Taiyin belongs to the Spleen, which governs the muscles. Metal of the Lung dislikes cold and is prone to external contraction; Earth of the Spleen and Stomach dislikes dampness and accepts all things. Observing his use of Dingxiang (Caryophylli Flos, Clove) and Guigui (Cinnamomi Ramulus, Cinnamon Twig), these are used to treat cold in the Lung; the use of Fuzi (Aconiti Lateralis Radix Preparata, Prepared Root of Chinese Aconite), Baizhu (Atractylodis Macrocephalae Rhizoma, Rhizoma of Atractylodes), and Banxia (Pinelliae Rhizoma, Pinellia Tuber) is to treat dampness in the Spleen. If the Lung truly has cold, and the Spleen truly has dampness accompanied by deficiency, then measuring the dosage and administering it, stopping when the illness is cured, what harm would there be?
However, this is not the case today. They merely see patients with delayed eruption of sores, fever, diarrhea, palpitations, rapid breathing, and thirst with desire to drink. Regardless of whether it is cold or heat, excess or deficiency, they indiscriminately administer Muxiang San (Aucklandiae Powder) and Yigong San (Yi Gong Powder). Occasionally, there are coincidental successes where effects are achieved immediately. But if misapplied, disaster ensues instantly. Why? Ancient practitioners, when compounding medicines and formulating prescriptions, employed guiding drugs (directors), supervising drugs, counteracting drugs, and drugs used according to specific indications. Although Qian Shi's formulas did not abandon Xixin (Asari Radix, Asarum Root), Dingxiang, Baizhu, Renshen (Ginseng Radix et Rhizoma, Ginseng Root), and Gancao (Glycyrrhizae Radix et Rhizoma, Licorice Root), they invariably included supervising and assisting herbs, rather than focusing solely on warming and tonifying! However, he used more cooling and cold-natured herbs, and only began to explore the method of assistance, without delving deep. One cannot speak of dreams before fools; Qian Shi's considerations were thorough, intending for enlightened individuals to expand and apply them.
Although the use of warming herbs for thirst and tonifying herbs for itching and collapse originated with Chen Shi, surpassing predecessors, his frequent use of Guizhi (Cinnamomi Ramulus, Cinnamon Twig), Fuzi, and Dingxiang, which are drying and hot, may not be appropriate. Why? Guizhi, Fuzi, and Dingxiang are indeed appropriate when there is cold and deficiency. But for cases of deficiency without cold, what harm could result? When Chen Shi formulated his prescriptions, there must have been cases of smallpox complicated by cold, making the use of drying, hot, and tonifying herbs suitable. Today, however, using such a biased formula for cases without cold complication, is it not excessively hot? I have synthesized the essence of various schools, sought their underlying principles, and applied them. I dare not rely blindly on established formulas. Let me cite a couple of examples to prove this.
My nephew, aged six or seven, suffered from smallpox with fever, slight thirst, and spontaneous diarrhea. A physician named Xiao Fangmai examined him and prescribed Muxiang San, adding ten grains of Dingxiang per dose. I harbored serious doubts. Observing the delayed eruption, it was indeed due to qi deficiency caused by diarrhea. Examining his excrement, it consisted of foul, stagnant, old accumulations, indicating downward flow due to steaming heat in the intestines and stomach. It was likely not cold and deficiency. Thus, I urgently stopped the medication after one dose had already been taken. Subsequently, I administered Huanglian Jiedu Tang (Coptis Decoction for Detoxification) with added Baizhu, giving ten doses to resolve the heat of Dingxiang. The diarrhea ceased, and the sores erupted. Afterwards, his skin often had slight heat, and boils and furuncles appeared on his hands and feet. After over a month of treatment with cooling and tonifying agents, he recovered.
Another male patient, aged sixteen or seventeen, presented with fever and coma, blindness, deafness, and pulses that were hollow, large, and slightly rapid in both hands. I knew this was due to labor injury (exhaustion). At that time, smallpox was prevalent in the village. Although unconscious, he drank medicine and ate porridge when offered. I instructed him to take a large decoction of Renshen, Gancao, Danggui (Angelicae Sinensis Radix, Dong Quai Root), Baizhu, and Chenpi (Citri Reticulatae Pericarpium, Tangerine Peel). After drinking more than thirty doses, the sores finally erupted. After another twenty-plus doses, pustules formed, leaving no intact skin on his body. Someone asked: "The condition is terrifying; why not use Chen Shi's complete formula?" I replied: "This is merely deficiency, without cold. Stick to the previous prescription." After dozens more doses, he recovered. Later inquiry into the cause revealed that four or five days prior, fearing the onset of smallpox, he had exerted himself greatly in gathering firewood, sweating profusely for consecutive days. Had Chen Shi's complete formula been used, would it not have led to regret?
In the spring of Jiashen year of the Zhizheng era, yang qi moved early. In the first lunar month, smallpox cases in the county were limited to one family. Suddenly, Chen Shi's formula was administered, resulting in the death of over a hundred children. Although this may be attributed to heavenly fate, I fear that human efforts were not fully exhausted either.