（出《灵枢》）
人之肥瘦、大小、寒温，与其气血多少，各有度也。何者？人有肥、有膏、有肉。 肉坚，皮满者，肥。
肉不坚，皮缓者，膏。皮肉不相离者，肉。（此言三人之形体也。）膏者，其肉淖，而粗理者身寒，细理者
身热。脂者，其肉坚，细理者热，粗理者寒。（此言寒热，是指其人本身气血之寒热，非发寒发热，恶寒
恶热之病也。凡人身皮肉之温，拊之各有轻重不同，是本于禀赋也。）膏者，多气而皮纵缓，故能纵腹垂腴。
肉者，身体容大。脂者，其身收小。（此言肥瘦大小。）膏者，多气，多气者热，热者耐寒。肉者，多血则充
形，充形则平。脂者，其血清，气滑少，故不能大。（此言气血多少。）此别于众人者也。众人者，皮肉脂膏
不能相加也。血与气不能相多，故其形不大不小，自称其身，命曰众人。（推论众人。）故治者，必先别其三
形，血之多少，气之清浊，而后调之，无失常经。是故膏人者纵腹垂腴，肉人者上下容大，脂人者虽脂不能
大也。（此概言治法，并补醒三形。）
（出《灵枢》）
重阳之人， 高高，言语善疾，举足善高，心肺之脏气有余，阳气滑盛而扬，故神动而气先行矣。
重阳之人而神不先行者，何也。曰∶此人颇有阴者
也。何以知其颇有阴也。曰∶多阳者多喜，多阴者多怒，数怒而易解，故曰颇有阴。其阴阳之离合难，故其
神不能先行也。（阳人血清而气滑，故喜怒即发而不留。阴人血浊而气滞，故神思不能自
畅，遂阳阴相激而多怒矣。经曰∶阴出之阳则怒。以是知人之性情，皆与气血相关也。）
(From *Ling Shu*)
The fatness or thinness, size, cold-heat constitution, and the quantity of Qi and Blood in each person have their respective standards. Why is this? Because people can be categorized into three types: Fei (Fat), Gao (Puffy), and Rou (Fleshy). Those with firm muscles and full skin are called Fei. Those with non-firm muscles and loose skin are called Gao. Those whose skin and flesh are closely attached and not easily separable are called Rou. (This describes the physical forms of these three types.) In Gao type individuals, the flesh is soft; those with coarse texture feel cold, while those with fine texture feel hot. In Zhi (Compact) type individuals, the flesh is firm; those with fine texture feel hot, while those with coarse texture feel cold. (Here, "cold-heat" refers to the inherent cold-heat nature of one's own Qi and Blood, not the pathological symptoms of aversion to cold/fever or aversion to heat/cold associated with external contraction or internal disorders. The temperature of a person's skin and flesh varies when touched, which is determined by congenital endowment.) Gao type individuals have abundant Qi and lax skin, thus they tend to have a protruding abdomen with hanging fat. Rou type individuals have a large body frame. Zhi type individuals have a compact and smaller body. (This describes differences in fatness/thinness and size.) Gao type individuals have abundant Qi; those with abundant Qi tend to be hot-tempered and can tolerate cold. Rou type individuals have abundant Blood, which fills the form, resulting in a balanced constitution. Zhi type individuals have clear Blood and smooth but scarce Qi, thus they cannot grow large. (This describes the variations in the quantity of Qi and Blood.) These are distinct from the general population (Zhong Ren). Zhong Ren refers to those whose skin, flesh, fat, and puffy tissue are in balance without excess; their Blood and Qi are also balanced, so their bodies are neither too large nor too small, fitting them well. Such individuals are called Zhong Ren. (This infers the characteristics of the general population.) Therefore, in treatment, one must first distinguish among these three body types, assess the quantity of Blood and the clarity/turbidity of Qi, and then regulate them according to standard principles. Thus, Gao type individuals have a protruding abdomen with hanging fat; Rou type individuals are large both above and below; Zhi type individuals, even if fatty, do not appear large. (This summarizes the therapeutic approach and reiterates the importance of distinguishing the three body types.)
(From *Ling Shu*)
Individuals with excessive Yang (Chong Yang Zhi Ren) exhibit an arrogant demeanor, speak rapidly, and lift their feet high. This is because the Qi of the Heart and Lung organs is in excess, causing Yang Qi to be smooth, vigorous, and soaring; consequently, the Shen (Spirit) moves quickly, and Qi acts in advance.
Why might the Shen of a Chong Yang individual not act in advance? The answer is: such a person possesses a considerable amount of Yin. How do we know they possess considerable Yin? We know that those with abundant Yang tend to be joyful, while those with abundant Yin tend to be irritable. If they become angry frequently but calm down easily, it indicates they possess considerable Yin. Because their Yin and Yang Qi are difficult to separate and harmonize, their Shen cannot act in advance. (In Yang-dominant individuals, Blood is clear and Qi is smooth, so emotions like joy or anger arise immediately and do not linger. In Yin-dominant individuals, Blood is turbid and Qi is stagnant, so the Shen cannot flow freely, leading to agitation between Yin and Yang and resulting in irritability. The Classics state: "When Yin emerges into Yang, anger occurs." From this, we understand that human temperament is intrinsically linked to Qi and Blood.)