伤寒者，冬时严寒，而人触冒之，寒气入腠理，搏于血气，则发寒热，头痛体疼，谓之
伤寒。又春时应暖而反寒，此非其时有其气，伤人即发病，谓之时行伤寒者。小儿不能触冒
寒气，而病伤寒者，多由大人解脱之时久，故令寒气伤之，是以小儿亦病之。
诊其脉来，一投而止者，便是得病一日，假令六投而止者，便是得病六日。其脉来洪者
易治，细微者难治也。
伤寒，是寒气客于皮肤，寒从外搏于血气，腠理闭密，冷气在内，不得外泄，蕴积生热
，故头痛、壮热、体疼。所以须解其肌肤，令腠理开，津液为汗，发泄其气，则热歇。
凡伤寒，无问长幼男女，于春夏宜发汗。又脉浮大宜发汗，所以然者，病在表故也。
伤寒，是寒气客于皮肤，搏于血气，腠理闭密，气不宣泄，蕴积生热，故头痛、体疼而
壮热。其人本脏气实者，则寒气与实气相搏，而壮热者，谓之挟实。实者有二种，有冷有热
，其热实，粪黄而臭；其冷实，食不消，粪白而酸气，比候知之。其内虽有冷热之殊，外皮
肤皆壮热也。
伤寒，是寒气客于皮肤，搏于血气，使腠理闭密，气不宣泄，蕴积生热，故头痛、体疼
而壮热也。其兼惊者，是热乘心，心主血脉，小儿血气软弱，心神易动，为热所乘，故发惊
。惊不止，则变惊痫也。
Shanghan (Cold Damage), refers to the condition where, during the severe cold of winter, the human body is exposed to and invaded by cold qi. The cold qi enters the Culi (the spaces between skin and flesh, including hair follicles and sweat glands), struggles with the blood and qi, thereby causing alternating chills and fever, headache, and body pain; this is called Shanghan. Furthermore, when spring should be warm but instead turns cold, this is an abnormal climate occurring out of season. When it injures people and causes immediate illness, it is called Shixing Shanghan (Epidemic Cold Damage). Children who suffer from Shanghan without having actively exposed themselves to cold are mostly due to adults leaving their clothes unfastened for too long, allowing cold qi to invade; thus, children also fall ill.
Upon examining the pulse, if the pulse beats once and then stops (indicating a short duration of disease onset in this context), it means the disease has been present for one day; if the pulse beats six times before stopping, it means the disease has been present for six days. A Hong (Surging) pulse indicates a condition that is easy to treat, whereas a Xi Wei (Fine and Minute) pulse indicates a difficult-to-treat condition.
Shanghan occurs when cold qi lodges in the skin, struggling externally with the blood and qi. The Culi become closed and dense, trapping cold qi inside which cannot diffuse outward. This accumulation generates heat, resulting in headache, high fever, and body pain. Therefore, it is necessary to release the exterior pathogen, open the Culi, allow body fluids to transform into sweat, and vent the accumulated qi, so that the heat will subside. For all cases of Shanghan, regardless of age or gender, sweating therapy is appropriate during spring and summer. Additionally, a Fu Da (Floating and Large) pulse indicates suitability for sweating therapy; this is because the pathogen is located at the exterior level.
Shanghan occurs when cold qi lodges in the skin, struggling with the blood and qi, causing the Culi to close and become dense, preventing the diffusion of qi and leading to heat generation through accumulation. Consequently, headache, body pain, and high fever occur. If the patient's internal Zang-Fu qi is originally substantial, the cold qi struggles with this substantial qi, resulting in high fever; this is termed Jia Shi (Accompanied by Excess Syndrome). There are two types of excess: Cold Excess and Heat Excess. In Heat Excess, stool is yellow and foul-smelling; in Cold Excess, food is not digested properly, stool is white, and has a sour odor. These patterns can be identified by these signs. Although there are differences between internal Cold and Heat excesses, the external skin always presents with high fever.
Shanghan occurs when cold qi lodges in the skin, struggling with the blood and qi, causing the Culi to close and become dense, preventing the diffusion of qi and leading to heat generation through accumulation. Thus, headache, body pain, and high fever occur. If accompanied by Jing Feng (Convulsion/Wind), it is because heat pathogen invades the Heart. The Heart governs the blood vessels. Since children have weak blood and qi, their Shen (Spirit/Mind) is easily disturbed. Being overwhelmed by heat, they develop convulsions. If the convulsions do not cease, they may transform into Jing Xian (Convulsive Epilepsy).