The various methods of meditation mentioned earlier serve as the foundation for cultivating the Great Dao. However, without understanding the secrets of cultivation, one merely practices the techniques aimed at enlightening the mind and seeing one's true nature. As for studying the dual cultivation of spirit and essence to achieve true enlightenment, it seems not as easy as what people talk about today. Some say that sitting in stillness for over a decade can make one an immortal; others claim that sixteen steps of practice can lead to immortality. Their theories vary, perhaps each having its own meaning. But I have heard that there is no fixed form or time limit in the path of immortality. If one rigidly adheres to sitting, it might easily cause harm rather than good, because worldly ties are not yet exhausted. One should not delve too deeply into these discussions. Cultivating the Dao, on the other hand, is real work without any illusion. It’s just that modern people favor Western doctrines and revere science, thus dismissing it as fictitious. Yet, they should know that human thought is limited and cannot fully comprehend many mysteries. Can a few branches of physics and chemistry encompass everything?