Mind, Spiritual Nature and Bodily Life
Among the three terms usually found in books on Inner Alchemy, Mind was regarded as substance, Spiritual Nature as the soul, namely the governing power, of the mind, and last but not least, Bodily Life as the Vital Breath. According to the Book of the Supreme Venerable Sovereign's Teachings on Cultivating Mind ( 《太上老君說了心經》Taishang Laojun Shuo Liaoxin Jing ), "Mind governs Spirit, whether in motion or at rest". The author argues that Mind controls the movements and functions of Spirit. In this sense, Mind is equal to substance, and Spiritual Nature equal to its function.
By comparison, Daoism attaches an importance to the inseparable link between Mind and Spiritual Nature. In the refinement of Inner Alchemy, the Enlightenment of Mind ( 明心 Mingxin ) and the Realization of Spiritual Nature ( 見性 Jianxing ) are equally emphasized. Among the two elements, the Enlightenment of Mind, or the Purifying of Mind, in another term, represents a process of cleaning the human Mind. Even in the years before the First Emperor of the Qin dynasty, "purifying human minds by [[[the Book of Changes]]" ( 《易》Yi ) had been popularly mentioned. In the later periods, Daoism borrowed concepts from the book in expounding Purifying Mind and other ideas about Inner Alchemy.
In Chinese, the character “purifying” consists of two parts, namely, “the sun” and “the moon”, which stands for Yang and Yin separately. It suggests that in order to purify human minds, Yang and Yin should be inseparably linked. When the two fundamental elements become one, Original Chaos ( 混沌 Huntun ) will return. Accordingly, the goal of Purifying Mind can only be achieved by ridding human beings of wisdom or desire, and returning to original simplicity, a state in which a complete circulation between Spirit and Vital Breath is attained. In another word, Substance and its Function are completely united.