Wu Shouyang on the Alchemical Embryo
Foundations of Internal Alchemy: The Taoist Practice of Neidan, by Wang Mu, page 107
Metaphorically it is called "embryo," as if there is truly an embryo. In fact, however, there is no embryo. Why is it so? Because according to the principle of giving birth, one generates the embryo of a child in the womb; and according to the principle of cultivating immortality, one generates an embryo of Spirit in the Heart. The worldly people hear the word "embryo" and say that within the womb there is truly an embryo, which then leaves and becomes "a body outside the body" (shen wai shen). This is truly risible. Essentially, the human nature is perfectly empty and perfectly numinous; it is devoid of a form and a body.
Source: Wu Shouyang (1574-1644), Xian Fo hezong yulu (Recorded Sayings on the Common Origin of the Immortals and the Buddhas), slightly abbreviated.
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