温病与伤寒迥不相同。伤寒必在冬月。温病四时皆有。伤寒乃感严寒之气。日传一经。宜分六经施治。温病乃感温
热秽浊之气。传变不定。宜分上中下三焦。及邪之在气在血以治之。以古书所列温病而论。春初风木当令而病者为风温。
春末夏初温热渐盛则为温热。夏令病暑热盛于湿者。为暑温。（暑温即受暑也。若过时而发。则为伏暑。）长夏初秋湿盛
于热者。为湿温冬令过暖。阳不潜藏。则为冬温。秽厉传染。家家如是。如徭役然。是为温疫。秽浊太甚。诸温夹毒。
则为温毒。以上各证。名目甚繁。而究其治法。只须细审温邪之兼湿与否。及湿温二邪。孰多孰少。以为用药之差别。
今以温邪之不兼湿者。统归风温类。列为上卷。温邪之兼湿者。统归湿温类。列为下卷。（叶氏温热论。薛氏温热赘言。
皆以风湿对待立论。故仿之。）而二卷之中。又各按三焦分为三篇。如此分门别类。庶可一目了然。惟上卷之风温温热
冬
温温毒。治法并皆相同。（温毒稍兼解毒）下卷之湿温暑温。则分湿多热多。用药稍有区别。（按湿热合邪之证。凡热多
于湿者。皆可以暑温法治之。湿多于热者。皆可以湿温法治之。不必拘定夏秋时令。亦有其人本体有湿。外感温热而病
者。不拘四时。皆为湿温。治法并同。古书分时论证。但言其大概耳。）至温疫乃一时厉气流行。或兼湿。或不兼湿。
初
无一定。须临时察其如何见证按两卷所列各条。根据法施治。故于二卷中俱列其目。总之温热最易伤阴。无论挟湿挟燥。
均须刻刻防其伤阴为第一要义。最忌麻黄桂枝羌活独活升麻柴胡等辛温升散之药。倘误用之。重伤其阴。必致轻病变重。
重病变为不起。不可不慎也。
温病与伤寒截然不同。伤寒必定发生在冬季。而温病在一年四季都可能出现。伤寒是由于感受了严寒之气，病情每天传变一经，治疗应当根据六经辨证来施治。温病则是由于感受了温热秽浊之气，病情传变没有定规，治疗应当根据上、中、下三焦辨证，以及邪气是在气分还是在血分来进行治疗。
根据古书中记载的温病来看：初春时节风木之气当令而发病的，称为风温；春末夏初，温热之气逐渐旺盛而发病的，称为温热；夏季发病，暑热盛于湿气的，称为暑温（暑温即感受暑邪所致。如果过了季节才发作，则称为伏暑）；长夏初秋，湿气盛于热气的，称为湿温；冬季气候过暖，阳气不能潜藏而发病的，称为冬温；秽浊疫气互相传染，家家户户都如此，如同服役一样普遍，这称为温疫；秽浊之气太甚，各种温病夹杂毒邪，这称为温毒。以上各种证候，名称非常繁多，但究其治疗方法，只需仔细审查温邪是否兼夹湿气，以及湿邪和温邪两者孰多孰少，以此作为用药的区别依据。
现在将不兼夹湿气的温邪，统一归入风温类，列为上卷；将兼夹湿气的温邪，统一归入湿温类，列为下卷。（叶天士的《温热论》、薛生白的《湿热条辨·赘言》，都是以风湿相对立来论述的，所以仿照这种做法。）而在上下两卷之中，又各自按照上、中、下三焦分为三篇。这样分门别类，才可以一目了然。
只有上卷中的风温、温热、冬温、温毒，治疗方法基本相同（温毒稍微兼用解毒之法）。下卷中的湿温、暑温，则根据湿多还是热多，用药稍有区别。（按湿热合邪的证候，凡是热多于湿的，都可以用治疗暑温的方法处理；湿多于热的，都可以用治疗湿温的方法处理，不必拘泥于夏秋时令。也有的人本身体质有湿，外感温热之气而发病的，不拘于四季，都属于湿温，治疗方法相同。古书按季节分类论证，只是说个大概罢了。）至于温疫，是一时厉气流行，或者兼夹湿气，或者不兼夹湿气，起初没有一定之规，必须临时观察其具体见证，按照上下两卷所列的各条法规进行治疗。所以在两卷中都列出了温疫的项目。
总之，温热之邪最容易损伤阴液，无论是否挟湿或挟燥，都必须时刻防备其损伤阴液，这是第一要义。最忌讳使用麻黄、桂枝、羌活、独活、升麻、柴胡等辛温升散的药物。如果误用这些药，会严重损伤阴液，必然导致轻病变重，重病变成不治之症，不可不谨慎啊。
Warm diseases are distinctly different from cold damage diseases. Cold damage diseases must occur in winter, whereas warm diseases can occur in all four seasons. Cold damage is caused by contracting severe cold qi; the pathogen transmits one meridian per day, and treatment should be administered according to the Six Meridians differentiation. Warm diseases, on the other hand, are caused by contracting warm, hot, turbid, and foul qi; the transmission of the pathogen is irregular, and treatment should be based on the Upper, Middle, and Lower Jiao differentiation, as well as whether the pathogen is in the Qi level or the Blood level.
According to the warm diseases listed in ancient texts: When wind-wood qi is dominant in early spring and disease occurs, it is called Wind-Warmth (Fengwen). When warm and hot qi gradually intensifies in late spring and early summer, it is called Warmth (Wenre). When disease occurs in summer with summer heat being more prevalent than dampness, it is called Summer-Warmth (Shuwen) (Summer-warmth refers to contracting summer heat. If it manifests after the season has passed, it is called Hidden Summer-heat [Fushu]). When dampness is more prevalent than heat in late summer and early autumn, it is called Damp-Warmth (Shiwen). When the winter climate is abnormally warm, causing yang qi to fail to store itself, it is called Winter-Warmth (Dongwen). When foul epidemic qi spreads contagiously, affecting every household similarly like forced labor, this is called Warm Epidemic (Wenyi). When the foul and turbid qi is extremely severe, and various warm diseases are complicated by toxic factors, it is called Warm-Toxicity (Wendu). Although the names for these various conditions are numerous, their treatment methods essentially require carefully examining whether the warm pathogen is complicated by dampness, and determining which is more prevalent between dampness and warmth, to differentiate medication.
Currently, warm pathogens that are not complicated by dampness are collectively categorized under Wind-Warmth and listed in Volume 1. Warm pathogens that are complicated by dampness are collectively categorized under Damp-Warmth and listed in Volume 2. (Ye Tianshi's *Treatise on Warm Heat* and Xue Shengbai's *Supplementary Remarks on Warm Heat* both establish their theories by contrasting wind and dampness; thus, we follow this approach.) Within these two volumes, each is further divided into three chapters according to the Upper, Middle, and Lower Jiao. This classification allows for clear understanding at a glance.
The treatments for Wind-Warmth, Warmth, Winter-Warmth, and Warm-Toxicity in Volume 1 are generally the same (with Warm-Toxicity slightly incorporating detoxifying methods). The treatments for Damp-Warmth and Summer-Warmth in Volume 2 differ slightly in medication depending on whether dampness or heat is predominant. (Regarding syndromes where dampness and heat combine: if heat is more prevalent than dampness, they can be treated using the method for Summer-Warmth; if dampness is more prevalent than heat, they can be treated using the method for Damp-Warmth. One need not rigidly adhere to the summer and autumn seasons. There are also cases where an individual’s constitution already possesses dampness, and upon contracting external warm heat, illness ensues regardless of the season; these all fall under Damp-Warmth with identical treatment methods. Ancient texts classified syndromes by season merely as a general guideline.) As for Warm Epidemic, it is a流行 of severe epidemic qi at a certain time, which may or may not be complicated by dampness, with no fixed initial presentation. One must observe the specific manifestations temporarily and treat according to the guidelines listed in both volumes. Therefore, items regarding Warm Epidemic are included in both volumes.
In summary, warm and heat pathogens easily injure Yin fluids. Regardless of whether there is complication by dampness or dryness, constantly preventing the injury of Yin fluids is the primary principle. It is most taboo to use acrid-warm ascending and dispersing herbs such as Ephedrae Herba (Mahuang), Cinnamon Twig (Guizhi), Notopterygii Rhizoma et Radix (Qianghuo), Angelicae Pubescentis Radix (Duohuo), Cimicifugae Rhizoma (Shengma), and Bupleuri Radix (Chaihu). If these are mistakenly used, Yin fluids will be severely damaged, inevitably causing mild conditions to become severe and severe conditions to become incurable. Caution is imperative.