Library

Zhenzhu (Pearl), cold in nature, non-toxic. It calms the heart spirit (Shen) and moistens the complexion. Applied to the eyes, it removes ocular membranes; inserted into the ears, it treats deafness; used for pediatric convulsions and epilepsy; especially effective in quenching thirst; also capable of descending phlegm. However, its internal use is rare; it is preserved for external therapeutic needs.

Zhenzhu (Pearl) is excellent for generating tissue and is a necessary drug for treating sores and toxins. However, if internal toxins are not yet cleared, using Zhenzhu (Pearl) prematurely to generate tissue will hinder wound closure.

Muli (Oyster Shell), salty in taste, neutral and slightly cold in nature, non-toxic. Those growing on the left side are of superior quality; it should be calcined before use. It enters the Shaoyin Kidney Meridian. It softens accumulations and masses, resolves tubercles, removes hardness under the hypochondrium, drains heat and reduces swelling, benefits essence, controls enuresis, stops night sweats with miraculous effect, breaks up old blood stasis, eliminates chronic phlegm, prevents nocturnal emissions (ghostly intercourse), and resolves qi stagnation. However, it can only serve as an assistant or guide drug. When combined with tonifying drugs, it tonifies; when combined with attacking drugs, it attacks; it shifts according to other herbs and cannot act independently.

Some doubt that Muli (Oyster Shell) is an astringent for essence, asking why the author omits discussing it. The answer is: Although Muli (Oyster Shell) has astringent properties for essence, it may cause further leakage of essence. This is not necessarily Muli's fault, but one must understand that Muli (Oyster Shell) astringes essence only after the pathways have been cleared (via diuresis); it does not stop leakage merely by astringency.

Some argue that Muli (Oyster Shell) is not an astringent. If it were solely for astringency, why does Zhang Zhongjing record in the *Shanghan Lun* (Treatise on Cold Damage) that for patients recovering from severe illness with water accumulation below the waist, the formula Muli Zexie San (Oyster Shell and Spurge Powder) is used? The response is: Alas! After severe illness, when water cannot descend downward, tonification is originally indicated to resolve water retention. However, after sweating, vomiting, or purging in cold damage, vital qi cannot recover rapidly; tonification would be too slow. Therefore, it is appropriate to follow the path of least resistance and use Zexie (Alisma Rhizome). Fearing that excessive water volume might lead to the loss of vital qi along with the water if only Zexie is used, Muli (Oyster Shell) is added to provide astringency amidst the draining action. Draining with astringency ensures water is expelled without depleting vital qi, embodying the principle of tonification within drainage. Who says Muli (Oyster Shell) is not an astringent?

Some question: If Muli (Oyster Shell) can be used with astringency in draining water, why can't it be combined with draining actions to stop seminal emission? The answer is: Water can be drained while being astringed, but essence cannot be astringed while simultaneously being drained. Essence leaks more when overly astringed; tonifying essence with astringents is futile. Therefore, for seminal emission, Muli (Oyster Shell) is absolutely contraindicated. (Comment: The analysis that astringing essence leads to further emission demonstrates profound insight.) However, there are cases where it is effective; this occurs when the "Jade Gate" (essence gate) is widely open, necessitating temporary closure. It cannot be relied upon as a long-term medication.

Someone asks: The meat of Muli (Oyster) is sweet and warm, which is Abalone meat. Muli (Oyster Shell) stops nocturnal emissions, but eating much Abalone causes men to lose beard hair. Why? The answer is: Muli (Oyster Shell) is the shell of the Abalone; they share the same nature and both possess astringent flavors. Excessive consumption blocks the Ren and Du meridians, preventing their qi from ascending to the lips and mouth, thus causing gradual loss of beard hair. In fact, consuming too much Muli (Oyster Shell) can also reduce beard growth.