An empty valley produces an echo; a moving form casts a following shadow. By observing one, the other can be deduced. Therefore, Qian Yi stated: "Heat appearing at specific times allows one to discern the condition of the Zang-Fu organs through the observation of heat." Furthermore, observing by the hours of the day: fever occurring during Yin, Mao, and Chen hours belongs to the Liver (Gan), manifesting as Shui Dou (water pox); fever during Si, Wu, and Wei hours belongs to the Heart (Xin), manifesting as Ban (macules/rashes); fever during Zi, Chou, and Yin hours belongs to the Spleen (Pi), manifesting as Pi Zhen (spleen rash); the Ear and Kidney (Shen) are not affected by turbid pathogens and have no specific symptoms, but if sores and rashes turn black, they belong to the Kidney; fever during Shen, You, and Xu hours belongs to the Lung (Fei), manifesting as Nong Pao (pustules). Observing that fever occurs at fixed times reveals the root origin of sores and rashes; this is also the "seeing the subtle to know the significant" precursor mentioned earlier.

When people are about to fall ill, they often fail to guard against it in minute details. Accumulation of the minute leads to damage; thus, ice three feet thick is not the result of one day's cold, and heat accumulation leading to toxic macules is not the result of one day's fever. All these are cases where the minute accumulates to become significant. Generally, children naturally possess abundant Yang and deficient Yin. Moreover, drinking hot milk morning and night, combined with heavy clothing for warmth and tight-fitting curtains, damages the skin and harms the blood vessels, causing sores to turn yellow and generating various diseases. In cases of toxic macules arising from accumulated heat, both the exterior and interior are affected by heat pathogens. It is advisable to take Shengma Tang (Cimicifugae Decoction), Xiaodu San (Detoxification Powder), Zicao Tang (Arnebiae Decoction), and oil preparations in advance for good results. There is also "Fa Ban" (eruption of macules) caused by Shanghan (Cold Damage), resulting from contracting cold pathogens and failing to resolve them properly. When pathogenic Qi becomes excessive and solid, it generates heat; toxic heat spreads over the whole body causing macules, resembling bites from mosquitoes or fleas, without forming blister-like sores, but merely red spots. This is a critical syndrome with a mortality rate of nine out of ten. If they turn into black spots, it is a syndrome with a mortality rate of nine out of ten, named Fa Ban. This differs from Chuang Dou (smallpox/variolous sores), yet all are collectively called Ban. Thus, it is mentioned here: Chuang Dou has several syndromes. Zhen (rashes) appear like Fei Chuang (prickly heat), emerging and healing simultaneously; this is called Fu Zhen (bran rash), with mild toxicity. Chuang Dou resembles bean grains; water blisters resemble teardrops and are greenish; small pustules contain pus and are larger. Their shapes vary. There are also "Xin Ban" (Heart Macules) and "Pi Zhen" (Spleen Rashes); each of the Five Zang organs has its specific manifestation, which must not be ignored.

When people live in peace and comfort, their Shen (Spirit) is calm, and their Qi and Blood (Qi Xue) are harmonious. When illness strikes, Yin and Yang become unbalanced. Although the degrees of excess and deficiency differ, this leads to unevenness in Deficiency and Excess patterns. Consequently, after sores and rashes emerge, they may not distribute evenly. Ancient treatment methods focused on venting the muscle layer and resolving toxicity, allowing pathogens to exit via the skin, dispersing and resolving Qi stagnation. With no obstruction, the eruption naturally becomes even. Using Bisheng San (Victory Guarantee Powder) and Kaidu Dan (Rapid Toxin Expelling Pill) facilitates rapid eruption, while Zicao Yin (Arnebiae Drink), Huisui Jiu (Coriander Wine), and Hongfen Dan (Red Powder Pill) ensure natural, even distribution.