Xuansu was a native of Hejian, he claimed. He sold pills made from the seeds of Croton tiglium in the city market, selling seven pills for one qian, claiming they could cure all kinds of illnesses. Prince Hejian was suffering from a tumor and bought the medicine to take; as a result, he expelled more than ten snakes. When asked about the meaning of the medicine, Su said: "The prince's tumor is a consequence of misfortune carried over from six generations, not something he himself has brought upon himself. "The prince often releases young deer out of compassion for their mothers; his kind heart has moved heaven, and thus he should encounter an ordinary person like me." An old retainer from the prince's household said: "My father has seen Su for generations, and Su has no shadow in form." The prince then called Su to be examined at noon, when it was indeed found that he had no shadow. The prince wanted to marry his daughter to him, but Su fled away during the night. Later people saw him beneath Changshan Mountain.

Substanceless and shadowless, at that time it was only Xuansu. The miraculous pills of Budeshen were entrusted to redeem the young deer. The Dao originated in Hejian, and at that time Xuansu was enjoying imperial favor. He soared like a dragon unbound by restraint, surpassing all others with his extraordinary talent.

らい The commentary says: The Yi Jing states that the Taiji gives rise to the Two Instruments. From the Two Instruments arise all things, and only then do people exist; With the existence of people comes birth and death. The meaning of life and death is thus clearly established. Indeed, all things in the world are spread out and formed as a whole, complete in every respect. How wondrous! How subtle! How refined! How minute! These matters cannot be discussed one by one. Sages looked upward to take the pattern from heaven, and downward to take the model from earth. The sun and moon move in their courses, the four seasons divide governance; the Five Stars are subject to control by Taiwei, overseeing nations without virtue. Auspiciousness or misfortune is foreseen beforehand, serving as a warning for the king's actions, words, and movements. Correspondence between response and imitation has always existed. Although heaven does not speak, its transformations and activities cannot be said to be nonexistent. The Zhou Shu records that Sang Wen asked Juanzi: "If there is death, how can it also be said that immortals exist? Are these two matters both true?" Juanzi replied: "Such statements may indeed coexist." The Yuan Shen Qi of the Xiao Jing says that no more than heaven and earth create spiritual voids, just as they establish the Five Sacred Mountains and set up the Three Platforms. Yang essence governs the exterior, while Yin essence governs the interior; their essences move upward and downward, weaving through all beings. The governance of the Dao is not uniform. For instance, all grasses and trees sprout in spring and wither in autumn—this is certain—but among trees there are more than one hundred and eighty kinds such as pines, cypresses, jiang, and sandalwood; among herbs there are zhiying, pingshi, lingzhao, huangjing, baihu, bamboo, and jiaohuo, all of which number in the tens of thousands and live on without dying. Even during severe winter, having endured frost and snow, they remain luxuriant and do not wither. Seeing such examples among these kinds of things, what is there to find strange about the existence of immortals?" I once obtained Master Ruan Cang of the Qin dynasty's Zhuanshen Tu (Illustrated Record of Immortals), which lists more than seven hundred people from six dynasties up to the present. The First Emperor of Qin was fond of matters related to immortals, hoping perhaps to achieve some success; therefore, alchemists gathered like fog, and prayers and sacrifices were widespread. They likely fabricated traces to rely on illusions, treating the empty as real; such accounts cannot be trusted. For example, Master Zhou Gong's Huang Lu records that Taibai descended to become a marquis or noble official. Yet the planet Suixing transformed into Ning Shou Gong and others; such sightings are not limited to one source. This is why sages do not openly discuss these matters, for they lack constancy. Nevertheless, although there are occasional manifestations, the Dao cannot be abandoned; to distance oneself and close it off is still a matter of upholding integrity and righteousness. Yet the Analects says, "Do not be fascinated by strange powers or disorderly spirits," from which its subtle meaning is clear.