四时者春夏秋冬，乃一岁代谢之序，其生长收藏，循环不息，生生无穷，此天之显明切
近之气。惟气有清和，则不能无偏胜。人在气交之中，受天地和气而长着，受天地戾气而致
疾。
以长夏暑湿挟杂，尤易伤人元气，消烁津液。湿为浊邪，最易伤阳。当天暑地热，人身
之气亦发越于外，腠理开，汗大泄，人之脾胃因之虚弱，外因湿蒸之酷尤易感受，随人身阴
阳之偏盛而为病。如奔走长途，受烈日之威，则为中暑，轻则六一散，重则白虎汤。若畏热
乘凉，暑为风伏，宜香薷饮加减为治。或居凉亭、水阁，多食瓜果、冷物，内外虚阳被遏，是
为寒暑伤阳，即宜用辛温治之，如大顺散、冷香饮子之类。若但多食生冷者，缩脾饮、正气
散随宜而用。若其人元气素虚，微感外暑，治以生脉散、清暑益气汤、消暑丸等醒脾阳、祛
湿热而已。
至于冬令，严寒肃杀之气为伤寒者，仲景言之详矣。惟阳气潜藏于内，天时晴燥，雨雪
稀少，乃成冬温之证，须用大剂清下，不得拘执《伤寒》成法以误人哉。近世此病甚多，尤宜
加审。轻则用杏苏饮，重则用葱豉汤加荆、薄、枳、桔、连翘、大贝以达表为治。
若时值初春，严寒将退，风木司权，其气善升而近燥，多犯上焦，故多身热、咳嗽、微恶
寒者，以黄芩汤为主方，随症加减，如薄、桔、荆、防、杏、苏、翘、贝、桑、菊、牛、蝉之类，取清
轻之味清肃肺卫；若失治久延，渐入荣分，有逆传、顺传之候。近世市医不知者，多徒守仲
景六经成法，辄投辛温表散，耗液伤阴，或变神昏、鼾睡、厥逆、瞀 ，或咳甚失血、延成痨
瘵，或胃实失下，谵狂痉搐，莫救者多矣。又有热极旁流，名为顺传胃府法，宜急下以存阴
液，然有舌苔黄燥裂纹可凭。奈何庸医不知者多，余以济世为怀，昼夜研钻，斯悟其致病之
由、挽救之法，历验不爽，随笔记之，以拯斯民之厄。
呜呼！自古迄今，无人发明春温、湿温、冬温之奥蕴，致误于庸俗者，不啻恒河沙数矣。
或者前哲知其所以然，而珍如拱璧，未能笔之于书，日久淹没者有之；或有其书，久久失传，
亦未可知也。更有误于经文者，如“秋伤于湿，冬生咳嗽”，细心研究“湿”字，的系传写之讹。
历来注家随文注释，亦未正其讹谬，又复曲为误引“长夏暑湿”，见证混淆于其间。岂知初秋
承长夏之末，暑湿伏气为患者，可以仍用清暑燥湿之法；时值夏、秋交替之时，最易变幻，直
迨深秋，燥令大行，往往盛于秋末、冬初，人在气交之中，受其戾气，伏而不宣，是为秋燥。其
症咳嗽，身热，胸闷，甚则谵妄、痉厥诸危候毕呈，当审天时之凉暖，而分寒燥、热燥之治，药
用温润、甘寒之品出入加减；又当验其舌苔，若焦黄燥裂，口渴能饮者，须用大剂清下，如
三黄承气等法，为釜底抽薪之治，切勿畏攻而留邪，致延日久大实而有羸状，误于温补不
起，以误人者。余为利人救危计，不得不将历验心法公诸宇内，以便后进得指归之益耳。
澜按∶四时，暑湿为最历。至于风温、秋燥、冬温等证，前人混于伤寒，拘执传经日数，
误于辛温表散。自先生阐明风性上升而气近澡，始犯上焦，治宜清肺轻剂，更复申明秋燥
一语，辨正经旨，有功后进，厥旨深切明矣。世人仅知“温邪上受”一言，叶氏创解，而不知叶
氏前已有言之哉！或者叶氏本此书而阐明其旨，由叶氏传播，亦未可知。谚云∶后来居上。
其斯之谓欤。
四时指的是春、夏、秋、冬，这是一年气候更替的顺序。其生长、化育、收敛、闭藏的过程循环不息，生生无穷，这是自然界明显且贴近人体的气候特征。由于气候有清和与偏胜之分，人处于天地气交之中，承受天地的和气而生长发育，若遭受天地的戾气（乖戾之气）则会导致疾病。
长夏季节暑湿夹杂，最容易损伤人的元气，耗竭津液。湿属于浊邪，最容易损伤阳气。正值天气炎热、地气蒸腾之时，人体之气也发散于体表，腠理（皮肤毛孔及纹理）开泄，汗出大量流失，导致脾胃因此虚弱，此时外界湿热熏蒸的酷热环境更容易被感受，随人体阴阳的偏盛而发生病变。例如长途奔走，遭受烈日暴晒，就会患上中暑，轻症用六一散，重症用白虎汤。如果因怕热而贪凉，导致暑气被风邪伏遏，适宜用香薷饮加减治疗。或者居住在凉亭、水阁，多吃瓜果、生冷食物，导致体内虚阳被遏制，这称为寒暑伤阳，应当立即使用辛温药物治疗，如大顺散、冷香饮子之类。如果只是多吃生冷食物，可酌情使用缩脾饮、正气散。如果其人元气素来虚弱，轻微感受外暑，治疗以生脉散、清暑益气汤、消暑丸等为主，旨在醒脾阳、祛湿热罢了。
至于冬季，严寒肃杀的气候导致伤寒，张仲景在《伤寒论》中已有详细论述。但若阳气潜藏于内，天时晴朗干燥，雨雪稀少，从而形成冬温证，必须使用大剂量的清热泻下药物，不能拘泥于《伤寒论》的成法以免误人。近代这类病症很多，尤其需要仔细审察。轻症用杏苏饮，重症用葱豉汤加荆芥、薄荷、枳壳、桔梗、连翘、大贝母以透达表邪为治。
如果正值初春，严寒即将消退，风木之气主事，其气善于上升且接近燥性，多侵犯上焦，所以多见身热、咳嗽、轻微恶寒的症状，以黄芩汤为主方，随症状加减，如加入薄荷、桔梗、荆芥、防风、杏仁、紫苏、连翘、贝母、桑叶、菊花、牛蒡子、蝉蜕之类，取用清轻之味以清肃肺卫；如果失治拖延日久，病邪逐渐进入营分，出现逆传或顺传的征候。近代许多市井医生不了解这一点，往往死守张仲景六经成法，随意投用辛温解表药，耗伤津液、损伤阴精，或者导致神志昏迷、鼾睡、厥逆、视物模糊，或者咳嗽剧烈导致咯血、拖延成痨瘵，或者胃实未及时攻下，导致谵语狂躁、痉挛抽搐，无法救治的情况很多。又有热极旁流的情况，名为顺传胃腑法，应当急下以保存阴液，但这要有舌苔黄燥裂纹作为依据。奈何不知此理的庸医很多，我怀着济世救人的情怀，昼夜钻研，才悟出致病的原因和挽救的方法，历经验证无误，随手记录下来，以拯救百姓的苦难。
唉！从古至今，没有人阐明春温、湿温、冬温的深奥蕴意，导致被庸俗之辈误解的，多得不可计数。或许前代哲人知道其中的道理，但视如珍宝，未能写入书中，久而久之被淹没的也有这种情况；或者有书存在，但久久失传，也未可知。更有甚者误解经文，如“秋伤于湿，冬生咳嗽”，细心研究“湿”字，确实是传抄书写时的讹误。历代注家顺着文字注释，也没有纠正这一错误，反而曲解引用“长夏暑湿”，使得见证混淆在其中。哪里知道初秋承接长夏之末，暑湿伏气为患者，还可以继续使用清暑燥湿的方法；当时值夏、秋交替之时，最容易变幻，直到深秋，燥令大行，往往盛行于秋末、冬初，人处于气交之中，遭受其戾气，潜伏而不宣发，这就是秋燥。其症状为咳嗽、身热、胸闷，甚至谵妄、痉厥等危重证候全部呈现，应当审察天时的凉暖，而区分寒燥、热燥的治疗，药物选用温润、甘寒之品出入加减；又应当查验其舌苔，如果焦黄燥裂，口渴能饮水的，必须使用大剂量的清热泻下药，如三黄承气等法，这是釜底抽薪的治疗方法，千万不要畏惧攻下而留邪，导致拖延日久，大实而有羸弱之状，误用温补无法治愈，从而误人的情况。我为利人救危考虑，不得不将历经验证的心得公之于众，以便后学者得到指引的益处。
澜按：四时之中，暑湿最为流行。至于风温、秋燥、冬温等证，前人将其混同于伤寒，拘泥于传经日数，误用辛温解表。自从先生阐明风性上升而气近燥，始犯上焦，治疗宜用清肺轻剂，又重申秋燥一语，辨别正统经旨，对后学有功，其主旨深切明了。世人只知道“温邪上受”一句话，认为是叶天士创立的解释，却不知道在叶氏之前就已经有人说过这话了！或许叶氏是依据这本书来阐明其旨意，经由叶氏传播开来，也未可知。谚语说：“后来居上。”说的就是这种情况吧。
The Four Seasons refer to Spring, Summer, Autumn, and Winter, which constitute the sequence of climatic change in a year. The processes of growth, maturation, harvest, and storage cycle endlessly, generating life infinitely; this is the manifest and proximate Qi (vital energy) of Heaven. Since Qi has both pure/harmonious and excessive/deficient aspects, it inevitably leads to imbalance. Humans exist within the intersection of Heaven and Earth's Qi; we grow and develop by receiving the harmonious Qi of Heaven and Earth, but fall ill when exposed to the hostile Qi (adverse pathogenic factors) of Heaven and Earth.
During the late summer, the mixture of Summerheat (Shu) and Dampness easily damages Yuan Qi (Original Energy) and consumes Body Fluids. Dampness is a turbid pathogen that most easily injures Yang Qi. When the weather is hot and the earth steams, the body's Qi also disperses outward, causing the Cou Li (pores and skin texture) to open and sweat to profusely escape. Consequently, the Spleen and Stomach become weak due to this loss. Under such conditions, the external environment's intense humid heat is easily invaded, leading to disease depending on the excess or deficiency of Yin and Yang in the body. For instance, running long distances under the scorching sun causes Zhong Shu (Heatstroke); mild cases are treated with Liu Yi San, while severe cases require Bai Hu Tang. If one seeks coolness due to fear of heat, allowing Summerheat to be trapped by Wind, Xiang Ru Yin should be modified for treatment. Alternatively, residing in cool pavilions or water towers and consuming too many melons, fruits, or cold foods can suppress the internal deficient Yang, a condition known as Cold-Heat injuring Yang, which requires immediate treatment with Acrid-Warm formulas such as Da Shun San or Leng Xiang Yin Zi. If only excessive consumption of raw/cold foods occurs, Suo Pi Yin or Zheng Qi San may be used appropriately. If a person has constitutionally deficient Yuan Qi and slightly contracts external Summerheat, treatment focuses on formulas like Sheng Mai San, Qing Shu Yi Qi Tang, or Xiao Shu Wan to awaken Spleen Yang and dispel Damp-Heat.
Regarding winter, the severe cold and killing Qi cause Shang Han (Cold Damage), which Zhang Zhongjing detailed extensively. However, if Yang Qi remains hidden internally while the weather is clear and dry with little rain or snow, Dong Wen (Winter Warmth) syndrome forms. This requires large doses of Clearing and Purging methods; one must not rigidly adhere to the established methods of *Shang Han Lun* to avoid harming patients. In recent times, such diseases are common and require careful examination. Mild cases use Xing Su Yin; severe cases use Cong Chi Tang added with Jing Jie, Bo He, Zhi Ke, Jie Geng, Lian Qiao, and Da Bei Mu to release the exterior.
If it is early spring, severe cold is retreating, and Wood/Wind Qi takes control. Its nature is ascending and close to Dryness, often attacking the Upper Jiao. Thus, symptoms such as fever, cough, and slight aversion to wind are common. Huang Qin Tang serves as the main formula, modified according to symptoms: adding Bo He, Jie Geng, Jing Jie, Fang Feng, Xing Ren, Su Ye, Lian Qiao, Bei Mu, Sang Ye, Ju Hua, Niu Bang Zi, Chan Tui, etc., utilizing light and clear flavors to purify and calm the Lung and Wei Qi. If untreated and prolonged, the pathogen gradually enters the Ying (Nutritive) level, showing signs of reverse transmission or forward transmission. Many modern city physicians do not understand this, blindly adhering to Zhang Zhongjing’s Six Channels methods, indiscriminately administering Acrid-Warm diaphoretics. This depletes fluids and injures Yin, potentially leading to coma, stertorous breathing, Jue Ni (cold extremities), blurred vision, severe cough with hemoptysis progressing to Lao Zhai (consumption), or fullness in the Stomach requiring purgation but neglected, resulting in delirium, mania, spasms, and convulsions, from which many cannot be saved. Another scenario is extreme heat with peripheral flow, termed forward transmission to the Stomach Fu organs, requiring urgent purgation to preserve Yin fluids, indicated by a yellow, dry, cracked tongue coating. Unfortunately, many ignorant quacks fail to recognize this. Out of compassion to save the world, I studied day and night, realizing the causes of these diseases and methods of rescue. Having verified their efficacy repeatedly, I recorded them to alleviate the suffering of the people.
Alas! From ancient times to the present, no one has elucidated the profound mysteries of Chun Wen (Spring Warmth), Shi Wen (Damp Warmth), and Dong Wen (Winter Warmth). Consequently, countless individuals have been misled by vulgar practitioners. Perhaps earlier sages understood the rationale but treasured it like jade, failing to write it down, leading to its eventual obscurity; or perhaps books existed but were lost over time. Furthermore, some misinterpret classical texts, such as "Injured by Dampness in Autumn, Cough arises in Winter." Careful study reveals that "Dampness" here is likely a transcription error.历代 commentators followed the text without correcting this error, further confusing matters by citing "Late Summer Summerheat-Dampness." They fail to realize that early autumn follows late summer; if Summerheat-Dampness latent pathogen prevails, clearing Summerheat and drying Dampness methods remain applicable. However, during the transition between Summer and Autumn, changes are frequent. By deep autumn, Dryness commands prevail, often peaking in late autumn and early winter. Humans, situated in the Qi intersection, suffer from this hostile Qi, which lies latent and unexpressed, constituting Qiu Zao (Autumn Dryness). Symptoms include cough, fever, chest tightness, and even critical signs like delirium, mania, spasms, and syncope. Treatment must assess the climate's coolness or warmth, distinguishing between Cold-Dryness and Heat-Dryness therapies, using moistening-warm or sweet-cold herbs with modifications. One must also examine the tongue coating; if it is scorched yellow, dry, and cracked, with thirst and ability to drink, large doses of clearing and purging agents like San Huang Cheng Qi Tang are necessary. This is a "pulling firewood from under the pot" strategy. Do not fear purgation and retain pathogens, leading to prolonged illness where extreme excess presents as weakness. Misusing warming tonics can lead to fatal errors. For the sake of benefiting others and saving the desperate, I publicly share these verified insights so future generations may benefit from guidance.
Lan notes: Among the Four Seasons, Summerheat-Dampness is the most prevalent. Previously, conditions like Feng Wen (Wind Warmth), Qiu Zao, and Dong Wen were conflated with Shang Han, and practitioners rigidly adhered to days of meridian transmission, mistakenly using Acrid-Warm diaphoretics. Since Mr. [the author] clarified that Wind nature ascends and approaches Dryness, initially attacking the Upper Jiao, and advocated light lung-clearing formulas, while reiterating the concept of Autumn Dryness to distinguish orthodox scriptural intent, he has greatly benefited future learners. His principles are profound and clear. The world only knows the phrase "Warm pathogens enter from above," attributing its explanation solely to Ye Tianshi, unaware that this was stated before Ye. Perhaps Ye based his elucidation on this book and propagated it, which is possible. As the proverb goes, "Latercomers surpass predecessors." This seems to be the case.