🌿 Folk Prescriptions

Since ancient times, people have desired health and long life. With rising material living standards and increasingly rich spiritual life, health and longevity have become globally significant issues. But how can one achieve health? How can one attain longevity? People have tried various methods seeking magical elixirs or resorting to mystical rituals, but all proved futile. Although no magical elixirs exist and mystical practices are nonexistent, human lifespan continues to increase.
Reports indicate that average human lifespan was only 20 in the 17th century, 30 in the 18th century, 40 before the 19th century, 55 in 1920, 60 in 1935, 68 in 1952, and now reaches around 70 years. Many developed countries have already entered "aging societies." It is foreseeable that by 2000, some nations and regions will see average lifespans approaching or reaching about 80 years. The ancient Chinese medical classic *Huangdi Neijing* states: "Live out your natural lifespan, reach a hundred years, then depart"—a dream once unattainable, but soon to become reality. Though numerous factors influence health and longevity—such as genetic inheritance, natural environment, socioeconomic conditions, scientific and technological progress, medical standards, nutrition, and personal occupation—the key factor remains whether one practices proper health preservation. Regarding the relationship between health preservation and longevity, *Huangdi Neijing* clearly states: "I have heard that ancient sages lived to a hundred years, yet their movements remained vigorous; today’s people, half a century old, already show signs of decline—is it due to changing times, or because people have lost the way?" This highlights that the key to physical health and longevity lies in whether people understand health preservation. Ancient wise men mastered health preservation and lived over 100 years without showing signs of aging, whereas modern individuals neglect health preservation and often fail to live past fifty, already appearing aged. While death is inevitable, postnatal regulation can gradually strengthen constitution, enhance recovery and anti-aging abilities, thus achieving longevity.
Traditional Chinese medicine offers rich theories and methods on health preservation, but the most important principle is "harmonizing with the seasons." As stated in *Ling Shu: Ben Shen*: "Thus, wise people nourish themselves according to the four seasons, adapting to cold and heat... Only so can they avoid harmful influences and enjoy long life and vitality." "Long life and vitality" means prolonging life and resisting aging. Why can life be prolonged? Because "harmful influences do not invade." Harmful influences refer to pathogenic factors; avoiding them means pathogens cannot attack. The key to preventing invasion lies in "adapting to the four seasons and adjusting to cold and heat"—an extremely important principle in traditional Chinese medicine health preservation, almost a secret to longevity. Why? *Su Wen: Bao Ming Quan Xing Lun* says: "Humans are born from the energy of heaven and earth, shaped by the laws of the four seasons." *Su Wen: Liu Jie Zang Xiang Lun* states: "Heaven nourishes humans with five qi, earth nourishes humans with five flavors." These emphasize that human survival depends on material conditions provided by heaven and earth, and adaptation to seasonal yin-yang changes is essential for growth. As the renowned Ming dynasty physician Zhang Jingyue said: "In spring, correspond with liver and nourish; in summer, correspond with heart and nurture growth; in late summer, correspond with spleen and transform; in autumn, correspond with lung and gather; in winter, correspond with kidney and store." This illustrates that the physiological activities of the five zang organs must adapt to seasonal yin-yang changes to maintain harmony with the external environment. This aligns with modern views that life arises from the interaction of matter and energy in nature. Humans must exchange food and air with nature to sustain normal metabolism. Traditional Chinese medicine theory holds that heaven has three yin and three yang six qi and the five elements—metal, wood, water, fire, and earth—while the human body also possesses three yin and three yang six qi and five element movements. Natural climate changes affect the movement of yin-yang six qi and five elements, and human physiology and pathology depend on the coordination of the six meridians and five zang organs' qi. Thus, human life activities are fundamentally aligned with natural changes. Furthermore, the movement of yin-yang and five elements in nature corresponds reciprocally with the movement of the five zang organs and six meridians in the human body—this is the concept of "unity of heaven and man," "the human body is a miniature universe," and "heaven and man correspond" or "man participates with heaven and earth"—the "oneness of heaven and man" view. As *Huangdi Neijing* states: "Man corresponds with heaven and earth, and responds to sun and moon." Here, sun and moon refer to their movements, i.e., celestial motions and climate changes. "Heaven and earth" refers to the entire natural world; "heaven and earth as one" means nature is an integrated whole. This understanding was clearly recognized early in *Huangdi Neijing*, such as in *Su Wen: Yin Yang Ying Xiang Da Lun*: "Heaven and earth are the upper and lower realms of all things" and "Heaven has four seasons and five elements, producing growth, maturation, storage, and harvest, generating cold, heat, dryness, dampness, and wind. Humans have five zang organs producing five qi, generating joy, anger, sorrow, worry, and fear." This indicates that all things in heaven and earth are not independent but interdependent, mutually influencing, interacting, connected, and reliant on each other. The four seasons and five elements in nature produce diverse climates. Under different climates, all living beings undergo processes of birth, development, and demise. Human zang organs also change accordingly, generating five emotions—joy, anger, sorrow, worry, and fear. "Four seasons" refer to spring, summer, autumn, and winter annually. Their formation stems from our planet Earth. Earth orbits the sun once every 365 days, 5 hours, 48 minutes, and 46 seconds (or 45 seconds)—commonly known as one year. Simultaneously, Earth rotates on its axis once every 24 hours—commonly known as one day. Its rotational axis forms a 66.5° angle with the orbital plane, resulting in the Northern Hemisphere being closer to the sun for half the year and the Southern Hemisphere for the other half. On the summer solstice, the sun directly shines on the Tropic of Cancer (23.5°N), and on the winter solstice, it shines directly on the Tropic of Capricorn (23.5°S). During other periods, the sun's direct rays move between these two latitudes. On the spring and autumn equinoxes, the sun passes directly overhead the equator twice, so Earth's annual orbit results in the sun's direct rays moving back and forth between the Tropics of Cancer and Capricorn. Consequently, sunlight distribution worldwide follows regular patterns, forming regular seasonal alternations. Each season has unique climatic characteristics: spring brings warmth and growth, summer brings heat and growth, autumn brings coolness and harvest, and winter brings cold and storage. Yet, they form an inseparable whole—a continuous process. Without growth, there would be no storage, nor next year’s renewal. It is precisely due to the alternation of cold, heat, warmth, and coolness, and the rise and fall of growth and storage, that normal biological development and growth occur. Traditional Chinese medicine explains this as follows: *Su Wen: Si Qi Tiao Shen Da Lun* states: "The four seasons’ yin and yang are the foundation of all things." "Four seasons’ yin and yang" refers to the annual changes in cold, heat, warmth, and coolness caused by the ebb and flow of yin and yang energy, hence called "four seasons’ yin and yang." For example, at winter solstice, yang begins to grow; from spring to summer, yang grows while yin declines—thus spring is warm, summer is hot. At summer solstice, yin begins to grow; from autumn to winter, yin grows while yang declines—thus autumn is cool, winter is cold. Due to the seasonal ebb and flow of yin and yang, we observe the biological pattern of growth in spring, development in summer, harvest in autumn, and storage in winter. Thus, four seasons’ yin and yang are the foundation of all things. Foundation means the origin of life and death. "Six qi" refers to the six climatic factors in nature: wind, cold, heat, dampness, dryness, and fire. These six factors arise from the annual changes in climate and possess distinct characteristics, yet they mutually regulate each other. Thanks to these normal seasonal changes, we experience the annual alternation of warmth, heat, coolness, cold, and growth-storage cycles. Thus, natural climate adjusts itself to benefit the growth and development of all things, forming an organic whole. This whole is constantly changing and follows regular patterns. Adhering to and utilizing this pattern maintains dynamic balance of yin and yang, benefiting humanity; disrupting this balance leads to disasters. "Humans are born from the energy of heaven and earth" also refers to the origin of human life, derived from heaven, earth, sun, and moon, primarily from the sun’s fire and earth’s water. All life depends on the sun—everything ultimately relies on solar light and heat energy. Light and heat are the energy sources for life on Earth. Without sufficient light and heat, life cannot emerge or survive. Engels said: "Our Earth itself survives only because of solar heat... Without the repulsive motion radiated by the sun, all motion on Earth would surely cease" (*Dialectics of Nature*). Our daily food comes directly or indirectly from plants, and fuels also originate from plants. Through photosynthesis, their energy comes from the sun. Thus, without the sun, there would be no life on Earth.