三焦有形、无形之说，越人、华佗、王冰、东垣皆曰有名无形；余则或言无状，或言有形，纷纭无定。愚意当以无
形之说为是，非若五藏五府各自成形，可以定其象也。《营卫生会篇》云∶“上焦如雾，中焦如沤，下焦如渎”，此三焦定
论也。以其无形，故举功用之相似者以比拟之也。雾、类乎气，《决气篇》所谓“若雾露之溉”是也。考沤、渎二字之义，
沤、渍也，渐也，渐渍之使柔烂也。则沤者状“腐熟水谷”之义，谓渐渍以化也。渎、浊也，通也，所以通垢浊也。则
渎者状分别清浊，即“决渎之官，水道出焉”之义也。其“三焦”字义，亦属无形，盖火灼则焦，火即是气，以少阳为
相火，即取“焦”字之义也。上、中、下、有分司之任，故曰“三”也。《营卫生会篇》云∶“上焦出于胃上口，并咽以
上，贯膈而布胸中。……中焦亦并胃中，出上焦之后。此所受气者，泌糟粕，蒸津液，化其精微，上注于肺脉，乃化而
为血，以奉生身，莫贵于此，故独得行于经隧，命曰营气。……下焦者，别回肠，注于膀胱而渗入焉。故水谷者，常并
居于胃中，成糟粕而俱下于大肠，而成下焦。”又云∶“营出于中焦，卫出于下焦。”《五味篇》云∶“谷始入于胃，其精微
者，先出于胃之两焦，以溉五藏，别出两行，营卫之道。”细玩《经》文，曰“出于胃上口”，“出上焦之后”，曰“成下
焦”，曰“胃之两焦”，皆见无形体之意焉。而细绎《经》旨，即营、卫之气所从出，其职司功用，莫非气之所为，故《中
藏经》曰∶“总领五藏六府、营卫经络、左右上下之气也。”至《本藏篇》有浓、薄、缓、急、直、结之说者，孙东宿谓
五藏、五府、五行，正配合者也，独三焦无合，故附膀胱而言，非谓三焦有物如是也。若《论勇篇》理纵、理横之说，
不过言其人之躯壳上下通体如此，故以“三”字贯之，而借“焦”字助语成辞，与《五味篇》所云“胃之两焦”句法相
仿耳。再以《背俞篇》五焦、七焦之文观之，则三焦纵横之句，亦可不必拘泥矣。使必以无形之说为误，岂越人、华佗
其才智反在后人下耶？
Regarding the theory of whether the Sanjiao (Triple Burner) is tangible or intangible, Yue Ren (Bian Que), Hua Tuo, Wang Bing, and Li Dongyuan all stated that it has a name but no form. I, however, have sometimes said it lacks shape and at other times claimed it has a physical form, leading to conflicting views without consensus. It is my opinion that the theory of its intangibility is correct, as it does not possess distinct physical shapes like the Zang organs (Yin organs) and Fu organs (Yang organs), which can be defined by their specific forms. The *Ling Shu: Ying Wei Hui Hui* chapter states: "The Upper Jiao is like mist, the Middle Jiao like fermentation, and the Lower Jiao like a ditch." This is the definitive description of the Sanjiao. Because it is intangible, metaphors of similar functions are used for comparison. "Mist" resembles Qi (Vital Energy); as described in the *Ling Shu: Jue Qi* chapter, "like mist and dew irrigating," refers to this state. Examining the meanings of "Ao" (fermentation/soaking) and "Du" (ditch/draining): "Ao" means soaking or gradual permeation, softening and rotting through gradual immersion. Thus, "Ao" describes the meaning of "rotting and ripening food and water," implying digestion through gradual permeation. "Du" means turbid or unblocking, used to clear waste and turbidity. Thus, "Du" describes the function of separating the clear from the turbid, corresponding to the meaning of "the official of draining, through which water passages flow." The etymology of the term "Sanjiao" also belongs to the intangible; essentially, fire scorching leads to charring, and fire itself is Qi. Since the Shaoyang (Lesser Yang) channel is considered the Ministerial Fire, the character "Jiao" (scorched/charring) is adopted for its meaning. The Upper, Middle, and Lower parts have divided responsibilities, hence the designation "Three." The *Ling Shu: Ying Wei Hui Hui* chapter states: "The Upper Jiao originates from the upper orifice of the stomach, runs along the pharynx above, pierces the diaphragm, and spreads in the chest... The Middle Jiao also resides within the stomach, emerging after the Upper Jiao. From the Qi absorbed here, dregs are separated, fluids are steamed and extracted, essence and subtle nutrients are transformed, flowing upward into the lung vessels, thereby transforming into Blood to nourish the body. Nothing is more precious than this, so it alone circulates through the meridians, named Ying Qi (Nutrient Qi)... The Lower Jiao separates from the ileum, pours into the bladder, and渗ates inward. Thus, food and water often reside together in the stomach, become dregs, and descend together into the large intestine, thereby forming the Lower Jiao." It further states: "Ying Qi originates from the Middle Jiao, Wei Qi (Defensive Qi) originates from the Lower Jiao." The *Ling Shu: Wu Wei* chapter states: "When grain first enters the stomach, its subtle essence first emerges from the two Jiaos of the stomach to irrigate the five Zang organs, dividing into two pathways, namely the channels of Ying Qi and Wei Qi." Carefully studying the classic texts, phrases such as "originating from the upper orifice of the stomach," "emerging after the Upper Jiao," "forming the Lower Jiao," and "the two Jiaos of the stomach" all imply the absence of a concrete physical body. Further analyzing the intent of the classics, since Ying Qi and Wei Qi arise from it, and their functions are entirely attributed to the activity of Qi, the *Zhong Zang Jing* states: "It commands the Qi of the five Zang and six Fu organs, Ying and Wei Qi, and the meridians throughout the left, right, upper, and lower body." Regarding the descriptions of thickness, thinness, laxity, tension, straightness, and knotting in the *Ling Shu: Ben Cang* chapter, Sun Yiqi (Sun Dongsu) argued that while the five Zang organs, five Fu organs, and Five Elements correspond perfectly, the Sanjiao has no specific pairing, so it is mentioned in relation to the Bladder. This does not mean the Sanjiao possesses such a physical entity. As for the theories of longitudinal and transverse fibers in the *Ling Shu: Lun Yong* chapter, these merely describe the structure of the human body's integument from top to bottom; thus, the character "Three" connects them, and "Jiao" is borrowed as an auxiliary word to complete the phrase, similar to the syntax in "the two Jiaos of the stomach" from the *Wu Wei* chapter. Furthermore, observing the references to "Five Jiaos" and "Seven Jiaos" in the *Ling Shu: Bei Shu* chapter, one need not rigidly adhere to interpretations of the longitudinal and transverse aspects of the Sanjiao. If one must insist that the theory of intangibility is erroneous, would it imply that the wisdom and talent of Yue Ren and Hua Tuo were inferior to those of later generations?