一、是书专为时病而设。时病者，乃感四时六气为病之证也，非时疫之时也。故书中专论四时之病，一
切温疫概不加载。倘遇瘟疫之年，有吴又可先生书在，兹不复赘。
一、诸论皆本《内经》、诸贤之说，毫不杜撰。但内有先宗其论，后弃其方，或先驳其偏，后存其法，
非既信又疑，盖欲择善而从。丰即偶有一得，亦必自载明白，俾阅者了然，并以寓就正之意。
一、诸法皆丰所拟，乃仿古人之方稍为损益。所用诸药，佥细心参究，不敢随意妄用以误人。
每法之后，又详加解释，俾学人知一药有一药之用。
一、诸方悉选于先哲诸书，以补诸法所不及。但其中有过汗者过下者，偏寒偏热者，不得不附敝意于后，
非丰之敢妄议古人，诚恐学人泥古方，医今病，不知化裁，致胶柱鼓瑟之诮。
一、诸案系丰临证时所笔者。每见古人之案，载危病多，载轻病少。不知轻者危之渐，故圣人有不忽
于细、必谨于微之训，所以危病轻病并载，使医者病者，预知防微杜渐耳。
一、是书以《阴阳应象大论》八句经旨为纲，集四时六气之病为目，总言之先圣之源，分论之后
贤之本，余论附于卷末。
经谓“冬伤于寒，春必病温，”是训人有伏气之为病也。夫冬伤于寒，甚者即病，则为伤寒，微者不
即病，其气伏藏于肌肤，或伏藏于少阴，至春阳气开泄，忽因外邪乘之，触动伏气乃发，又不因外邪而
触发者，偶亦有之。其藏肌肤者，都是冬令劳苦动作汗出之人；其藏少阴者，都是冬不藏精肾脏内亏之
辈。此即古人所谓最虚之处，便是容邪之处。何刘松峰、陈平伯诸公，皆谓并无伏气，悖经之罪，其何
逭乎！据丰论春时之伏气有五∶曰春温也，风温也，温病也，温毒也，晚发也。盖春
温者，由于冬受微寒，至春感寒而触发。风温者，亦由冬受微寒，至春感风而触发。温病者，亦由冬受微寒，
寒酿为热，至来春阳气弛张之候，不因风寒触动，伏气自内而发。温毒者，由于冬受乖戾之气，至春夏之交，
更感温热，伏毒自内而发。晚发者，又由冬受微寒，当时未发，发于清明之后，较诸温病晚发
一节也。此五者，皆由冬伤于寒，伏而不发，发于来春而成诸温病者，当辨别而分治之。
程曦曰∶“推松峰与平伯，皆谓并无伏气，有由来也，一执
《云笈七签》冬伤于汗之句，一执钱氏冬伤寒水之脏之文。殊
不知两家只顾一面文章，全罔顾春伤、夏伤、秋伤之训，作何等解。思二先生天资高迈，亦受其蒙，不
正其讹，反助其说，毋怪后之医者，统称暴感，恣用发散，羌、防、麻、桂，逼汗劫津，误人
性命，固所不免，此不得不归咎于作俑之人也。”
一、本书专为时令疾病而设。所谓“时病”，是指感受四季六气（风、寒、暑、湿、燥、火）而引发的病证，并非指“时疫”（流行性传染病）。因此，书中专门论述四季的疾病，一切温疫一概不收录。如果遇到瘟疫流行的年份，有吴又可先生的著作可供参考，此处不再赘述。
二、书中的各种论述都依据《黄帝内经》及历代贤者的学说，绝不凭空捏造。但其中有的先采纳其理论，后摒弃其方剂；有的先驳斥其偏颇之处，后保留其治疗方法。这并非既相信又怀疑，而是为了择善而从。我雷丰即使偶有心得，也必定明确记载，使读者一目了然，并以此表达向高明请教之意。
三、书中的各种治法都是我拟定的，是仿照古人的方剂稍作增减而成。所用的各种药物，我都仔细研究推敲，不敢随意滥用以免误人。每种治法之后，又详细加以解释，使学习者知道每一味药都有其特定的用途。
四、书中的各种方剂都选自前代哲人的著作，以补充各种治法所不及之处。但其中有过于发汗的、过于攻下的、过于寒凉的、过于温热的，不得不附上我的意见在后面。这并不是我敢于妄议古人，实在是担心学习者拘泥于古方来治疗今天的疾病，不知道灵活变通，从而导致被人讥笑为“胶柱鼓瑟”（比喻拘泥成法，不知变通）。
五、书中的医案是我在临证诊疗时记录的。每次看到古人的医案，记载危重病的多，记载轻病的少。却不知道轻症往往是重症的开端，所以圣人教导不要忽视细微之处，必须在萌芽阶段谨慎对待。因此，危重病和轻病一并记载，使医生和患者都能预先知晓防微杜渐的道理。
六、本书以《黄帝内经·素问·阴阳应象大论》中的八句经文作为纲领，汇集四季六气引起的疾病作为条目，总括而言是先圣的源头，分论则是后贤的根本，其余论述附在卷末。
经文说：“冬伤于寒，春必病温。”这是告诫人们有“伏气”（潜伏体内的邪气）致病的情况。冬天受寒，严重的立即发病，这就叫伤寒；轻微的当时不发病，邪气潜伏在肌肤之间，或者潜伏在少阴经，到了春天阳气升发疏泄之时，忽然因为外邪侵袭，触动伏气而发作；也有不因外邪触发而偶然自发的情况。潜伏在肌肤的，都是冬天劳作辛苦、动作出汗的人；潜伏在少阴的，都是冬天没有藏精、肾脏内亏的人。这就是古人所说的“最虚之处，便是容邪之处”。为什么刘松峰、陈平伯诸位先生，都说根本没有伏气？这是对违背经典教义的罪责，怎么能逃避呢！根据我的论述，春季的伏气有五种：分别是春温、风温、温病、温毒、晚发。所谓春温，是由于冬天受了轻微寒气，到春天感受寒气而触发。所谓风温，也是由于冬天受了轻微寒气，到春天感受风邪而触发。所谓温病，也是由于冬天受了轻微寒气，寒气酝酿化为热，到来年春天阳气弛张的时候，不因风寒触动，伏气从内部自发出来。所谓温毒，是由于冬天受了乖戾不正之气，到春夏之交，更感受温热之气，伏毒从内部自发出来。所谓晚发，又是由于冬天受了轻微寒气，当时未发作，在清明节气之后才发作，比一般的温病晚发一个阶段。这五种情况，都是由冬天受寒，邪气潜伏而不发作，到来年春天才形成各种温病，应当辨别清楚并分别治疗。
程曦说：“推究刘松峰和陈平伯，都说没有伏气，是有原因的。一个执着于《云笈七签》中‘冬伤于汗’的句子，一个执着于钱乙《小儿药证直诀》中‘冬伤寒水之脏’的文章。殊不知这两家只顾片面文章，完全不顾《内经》中关于春伤、夏伤、秋伤的教诲，该如何解释？我想这两位先生天资高超，也受到了蒙蔽。如果不纠正他们的错误，反而助长他们的说法，难怪后来的医生，统称暴感（突然感受的外邪），肆意使用发散药物，羌活、防风、麻黄、桂枝，逼迫出汗劫夺津液，误人性命，固然在所难免，这不得不归咎于始作俑者。”
1. This book is specifically designed for seasonal diseases (Shi Bing). "Seasonal diseases" refer to conditions caused by the pathogenic influence of the six Qi (Wind, Cold, Summer-heat, Dampness, Dryness, Fire) of the four seasons, not referring to "epidemic diseases" (Shi Yi). Therefore, this book exclusively discusses diseases of the four seasons and does not include any warm epidemics. In years when plagues occur, one may refer to Mr. Wu Keyou's works; there is no need to repeat them here.
2. All discussions in this book are based on the *Huangdi Neijing* (Yellow Emperor's Inner Canon) and the theories of past sages, without any fabrication. However, some sections first adopt a theory and later discard its prescription, or first refute its bias but retain its method. This is not due to skepticism, but rather to select the good and follow it. Even if I, Lei Feng, have occasional insights, I will record them clearly so that readers understand at a glance, thereby expressing my intent to seek correction from experts.
3. All treatment methods presented are proposed by me, modeled after ancient prescriptions with slight modifications. The herbs used have been carefully studied and researched; I dare not use them arbitrarily to avoid harming patients. After each method, detailed explanations are provided so that students understand the specific utility of each herb.
4. All formulas are selected from the works of past philosophers to supplement the limitations of various methods. Some of these involve excessive sweating, excessive purging, excessive cold, or excessive heat. It is necessary to append my comments afterwards. This is not out of arrogance to criticize ancients, but out of fear that students might rigidly apply ancient formulas to contemporary diseases without flexible adaptation, leading to ridicule for being inflexible ("gluing the tuning pegs").
5. The medical cases recorded are those documented during my clinical practice. Observing ancient case records, they mostly describe critical illnesses and rarely mild ones. One should realize that mild conditions are often the precursors to critical ones. Thus, the Sages taught not to neglect details and to be cautious of subtle signs. Therefore, both critical and mild cases are recorded to enable doctors and patients to prevent problems before they arise and stop them from growing.
6. This book takes eight lines from the *Da Lun Yin Yang Ying Xiang* (Great Treatise on the Correspondence of Yin and Yang) in the *Neijing* as its outline, collecting diseases caused by the six Qi of the four seasons as items. Generally speaking, it traces the source of the ancient sages; specifically, it discusses the foundation of later scholars. Other discussions are attached at the end of the volume.
The classic states: "If one is injured by Cold in winter, one will inevitably suffer from Warmth in spring." This instructs us that diseases can be caused by latent Qi (Fu Qi). If injured by Cold in winter and the illness manifests immediately, it is called Shanghan (Cold Damage). If mild and not immediate, the pathogenic factor lies dormant in the skin and muscles, or in the Shaoyin channel. When Yang Qi opens and disperses in spring, an external pathogen may trigger the latent Qi, causing disease onset. Occasionally, it may also arise spontaneously without external triggering. Those with latent factors in the skin and muscles are usually those who labored and sweated during winter activities. Those with latent factors in the Shaoyin are usually those who failed to conserve Jing (Essence) in winter, resulting in Kidney deficiency. As the ancients said, "The most deficient place is where pathogens reside." Why do figures like Liu Songfeng and Chen Pingbo deny the existence of latent Qi? They commit the sin of contradicting the classics; how can they escape blame? According to my analysis, there are five types of latent Qi in spring: Chunwen (Spring Warmth), Fengwen (Wind Warmth), Wenbing (Warm Disease), Wendu (Warm Toxicity), and Wanfa (Late Onset).
- Chunwen arises from slight Cold acquired in winter, triggered by Cold sensation in spring.
- Fengwen also arises from slight Cold acquired in winter, triggered by Wind sensation in spring.
- Wenbing arises from slight Cold acquired in winter, which ferments into Heat. When Yang Qi expands in spring, the latent Qi erupts internally without needing Cold or Wind triggers.
- Wendu arises from aberrant Qi acquired in winter. At the transition between spring and summer, influenced by Warmth, latent toxicity erupts internally.
- Wanfa arises from slight Cold acquired in winter, which did not manifest initially but appears after the Qingming solar term, occurring one stage later than typical Warm Diseases.
These five types all result from Winter Cold injury, lying dormant until spring, forming various Warm Diseases. They must be differentiated and treated separately.
Cheng Xi stated: "Regarding Liu Songfeng and Chen Pingbo's denial of latent Qi, their reasoning has origins. One clings to the phrase 'Winter injury by sweat' from *Yunji Qiqian*, and the other to Qian Yi's text regarding 'Winter Cold injuring the Water organ.' Neither side considers only half the argument, completely ignoring the teachings on Spring, Summer, and Autumn injuries. How should these be interpreted? Although these two gentlemen possessed high intellectual capacity, they were misled. If we do not correct their errors but instead support their views, it is no wonder later physicians uniformly attribute such cases to sudden external contraction (Bao Gan), recklessly using dispersing agents like Qianghuo, Fangfeng, Mahuang, and Guizhi to force sweating and deplete Jin-Ye (Body Fluids), thereby endangering lives. This is inevitable, and the blame must fall on the originators of these erroneous theories."