伤寒传变，止言足经，不言手经，原本《内经》热病论中六节之文也。自草窗刘氏不明其理，创论伤
寒只传足经，不传手经，诞妄欺人，莫此为甚。人之金、火两脏，不过以五行为分属，岂有真金、真火，
故不能伤乎？至陶节庵易之以伤足不伤手。夫既不伤手，何手六经之见症，亦变见于伤寒症中也？再观本
经云三阴三阳、五脏六腑皆受病，则手经亦在其中矣。故仲景有心、肝、肺、脾、肾五脏之绝症。顾本
经不言手经者，以伤寒表邪也，欲求外症，但当察于周身，而周身上下脉络，惟足六经尽之，手经无能遍
也。且手经所至，足经无不至者，故但言足经，而手经即在其中。此本经止言足者，为察周身之表证
也。疑义至今，皆惑于刘氏之妄言耳！况人身脏腑在内，经络在外，故脏腑为里，经络为表。在表者手足
各有六经，是为十二经脉。以十二经脉分阴阳，则六阳属腑为表，六阴属脏为里。以十二经脉分手足，则
足经之脉长而远，自上及下，遍络四体，故可按之以察周身之病；手经之脉短而近，皆出入于足经之间，
故凡诊伤寒者，但言足经，不言手经也。
《活人书》有云∶中脘有痰，令人憎寒壮热，胸膈痞闷，有类伤寒。又云∶伤寒只传足经，不传手
经。地之寒、暑、风、湿，皆作蒸气，足常履之，遂成香港脚，所以病症与伤寒相类。此等议论，大是惑人。夫
伤寒为热病，有六经传变之异。痰本人身津液血凝气滞而成，未尝有六经之变症。至于香港脚，为寒、湿、热
三气之感，虽东垣有南北内外之分，而孙真人详香港脚见症甚悉，亦未始有六经之别。何将此二证竟以类伤
寒混同名之？似欲以治伤寒之法治痰与香港脚耶！凡治病必正证之名，名不正则治疗无据矣。
The transmission and transformation of Shanghan (Cold Damage) disease are described only in terms of the Foot meridians, not the Hand meridians. This originates from the text on "Six Sections" in the *Treatise on Heat Diseases* within the *Neijing* (Classic of Internal Medicine). Since Liu Wansu (Liu Zhaocuang) failed to understand this principle, he created the theory that "Shanghan only transmits through the Foot meridians, not the Hand meridians." This absurd and deceitful claim is unparalleled in its audacity. The Lung (Metal) and Heart (Fire) organs in the human body are merely categorized according to the Five Elements; does this imply there is literal metal or fire, and thus they cannot be injured? Later, Tao Jie'an (Tao Hua) changed this to "injury to the Foot, not the Hand." If the Hand meridians are not injured, why do the symptoms of the Hand Six Meridians also manifest in Shanghan diseases? Furthermore, observing the original text which states that "the Three Yin and Three Yang, the Five Zang and Six Fu organs all receive disease," it is clear that the Hand meridians are included therein. Thus, Zhang Zhongjing mentioned terminal syndromes of the Heart, Liver, Lung, Spleen, and Kidney. The reason the original text does not explicitly mention the Hand meridians is that Shanghan involves exterior pathogens. To seek external symptoms, one must examine the entire body. The meridians throughout the upper and lower body are fully covered by the Foot Six Meridians, whereas the Hand meridians cannot reach everywhere. Moreover, wherever the Hand meridians extend, the Foot meridians also reach. Therefore, speaking only of the Foot meridians implicitly includes the Hand meridians. The reason the original text mentions only the Foot meridians is for the purpose of examining exterior syndromes of the whole body. The doubts persisting to this day are all due to confusion caused by Liu's false statements!
Furthermore, the Zang-Fu organs are internal, while the meridians are external; thus, the Zang-Fu constitute the Interior, and the meridians constitute the Exterior. In the Exterior, there are six meridians each for the Hand and Foot, forming the Twelve Primary Meridians. When dividing the Twelve Primary Meridians by Yin and Yang, the Six Yang meridians belong to the Fu organs and represent the Exterior, while the Six Yin meridians belong to the Zang organs and represent the Interior. When dividing them by Hand and Foot, the Foot meridians are long and distant, extending from top to bottom and connecting all four limbs, allowing diseases of the whole body to be examined through palpation; the Hand meridians are short and proximate, intersecting between the Foot meridians. Therefore, those who diagnose Shanghan speak only of the Foot meridians and not the Hand meridians.
The *Huoren Shu* (Book of Saving Lives) states: "Phlegm in the Zhongwan area causes aversion to cold and high fever, with chest and diaphragm stuffiness and oppression, resembling Shanghan." It also states: "Shanghan only transmits through the Foot meridians, not the Hand meridians." The cold, heat, wind, and dampness of the earth all transform into vapors. Since the feet constantly tread upon them, Hongxiangjiao (Hongjiaojiao / Beriberi) is formed, so its symptoms resemble Shanghan. These discussions are highly misleading. Shanghan is a heat disease with variations in transmission through the Six Channels. Phlegm is formed by the coagulation of body fluids and blood and the stagnation of Qi; it never exhibits changes through the Six Channels. As for Hongxiangjiao, it results from the invasion of Cold, Dampness, and Heat pathogens. Although Li Dongyuan distinguished between North/South and Internal/External, Sun Simiao detailed the symptoms of Hongxiangjiao very thoroughly, yet never mentioned distinctions of the Six Channels. Why should these two conditions be confusedly named as "resembling Shanghan"? It seems one wishes to use the methods for treating Shanghan to treat Phlegm and Hongxiangjiao! In treating diseases, one must correctly name the syndrome. If the name is incorrect, there is no basis for treatment.