Mind is very fickle, like mercury. Fickle mind, with no discrimination of purity and impurity, flows arbitrarily, conducts itself with no restraints. Because of its unrestrained conduct, the mind influencing the organs of the body not only causes them to become sick, but endangers itself. If the mind becomes one-pointed or fixed, it regulates the organs of the body and protects them from disease. Illusion is also a function of the mind, leading to many sicknesses.
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