Since ancient times, people have longed for health and longevity. With rising material standards and richer spiritual lives, health and longevity have become global concerns. But how can one achieve health? How can one live long? People have tried countless remedies and mystical practices, but all proved futile. Though no magical elixirs exist and no mysticism works, human lifespan continues to grow.
Reports indicate that average life expectancy was only 20 in the 17th century, 30 in the 18th, 40 before the 19th, 55 in 1920, 60 in 1935, 68 in 1952, and now reaches around 70. Many developed nations have already entered “aging societies.” It’s foreseeable that by 2000, some countries’ average lifespans will approach or reach 80. The ancient Chinese classic *Huangdi Neijing* speaks of “living to the full span of life, reaching a hundred years and passing peacefully”—a dream soon to become reality. While numerous factors influence health and longevity—such as genetics, environment, socioeconomic status, science and technology, medical care, nutrition, and occupation—the most critical factor is whether one practices proper health maintenance. The *Huangdi Neijing* clearly states: “I’ve heard that ancient people lived to a hundred, yet remained active and vigorous; today’s people, half that age, are already frail. Is it due to different eras, or have people lost the way?” This highlights that the key to health and longevity lies in understanding and practicing health preservation. Ancient sages mastered health principles, living beyond 100 with youthful vigor. Today’s people, neglecting health, often decline before fifty. Death is inevitable, but through postnatal adjustment, one can gradually strengthen the body, improve recovery and anti-aging abilities, achieving longevity.
Traditional Chinese medicine offers rich theories and methods for health preservation, but the core principle is “adapting to the seasons.” As stated in *Ling Shu: Ben Shen*: “Thus, wise people must follow the four seasons and adapt to cold and heat… Only then can they avoid evil influences and live long.” “Long life” means prolonged existence and resistance to aging. Why can life be extended? Because “evil influences do not enter.” Evil influences refer to pathogenic factors. Their absence stems from “adapting to the four seasons and balancing cold and heat”—a fundamental principle of TCM, almost a secret to longevity. Why? *Su Wen: Bao Ming Quan Xing Lun* says: “Humans are born from heaven and earth’s energy, shaped by the four seasons.” *Su Wen: Liu Jie Zang Xiang Lun* adds: “Heaven nourishes us with five qi, earth with five flavors.” This shows humans depend on the material provided by heaven and earth to survive, and must adapt to the changing patterns of the four seasons to grow. As the famous Ming dynasty physician Zhang Jingyue said: “Spring corresponds to the liver and nourishes growth; summer to the heart and promotes flourishing; late summer to the spleen and transformation; autumn to the lung and harvest; winter to the kidney and storage.” This illustrates that internal organ functions must align with seasonal changes to maintain harmony with the external environment. This view aligns with modern understanding that life arises from interactions between matter and energy in nature. Humans must ingest food, breathe air, and exchange substances with nature to sustain normal metabolism. TCM theory holds that heaven has six qi—three yin and three yang—and the five elements (metal, wood, water, fire, earth), mirroring similar movements within the human body. Natural climate changes affect the movement of yin-yang and five elements, influencing physiological and pathological processes. Thus, human life and natural changes operate on the same principle. Furthermore, the movements of yin-yang and five elements in nature correspond reciprocally with those in the human body—this is the “unity of heaven and man,” “the human body is a miniature universe,” and “harmony between man and heaven,” reflecting the “oneness of heaven and man.” As the *Huangdi Neijing* says: “Man is in harmony with heaven and earth, and corresponds with the sun and moon.” Here, “sun and moon” refer to celestial movements and climate changes. “Heaven and earth” denote the entire natural world. “Heaven and earth as one” means nature is a unified whole. This concept was clearly recognized in the *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, harvest, and storage, generating cold, heat, dryness, dampness, and wind. Humans have five zang organs transforming into five emotions, producing joy, anger, sorrow, worry, and fear.” This means all things in heaven and earth are interconnected, mutually influencing and dependent. The four seasons and five elements create diverse climates, driving biological cycles of birth, growth, decline, and death. Human organs undergo corresponding changes, generating five emotions. “Four seasons” refer to spring, summer, autumn, and winter. Earth orbits the sun every 365 days, 5 hours, 48 minutes, and 46 seconds (or 45), forming a year. Earth rotates once every 24 hours, forming a day. Its axis tilts at 66.5° relative to its orbital plane, meaning for half the year the Northern Hemisphere is closer to the sun, and for half the year the Southern Hemisphere is. On the summer solstice, the sun shines directly on the Tropic of Cancer (23.5°N); on the winter solstice, it shines on the Tropic of Capricorn (23.5°S). During equinoxes, the sun crosses the equator twice, shining directly overhead. Thus, as Earth orbits the sun, the sun’s direct rays move back and forth between the tropics, creating regular seasonal changes worldwide. Each season has distinct characteristics: spring warms and grows, summer heats and flourishes, autumn cools and harvests, winter freezes and stores. Yet they form an inseparable whole—a continuous process. Without growth, there can be no storage, nor renewal the next year. It is precisely due to the alternation of cold, heat, warmth, and coolness that life develops normally. TCM explains this: *Su Wen: Si Qi Tiao Shen Da Lun* says: “The four seasons and yin-yang are the foundation of all things.” “Four seasons and yin-yang” refers to the annual changes in cold, heat, warmth, and coolness, formed by the rise and fall of yin and yang energies—hence “four seasons and yin-yang.” For example, yang begins at winter solstice; from spring to summer, yang grows and yin declines, hence spring’s warmth and summer’s heat. Yin begins at summer solstice; from autumn to winter, yin grows and yang declines, hence autumn’s coolness and winter’s cold. Due to these seasonal changes in yin-yang, we see the natural cycle of spring growth, summer flourishing, autumn harvest, and winter storage—thus, four seasons and yin-yang are the foundation of all things. “Foundation” means the origin of life and death. “Six qi” refers to the six climatic factors—wind, cold, heat, dampness, dryness, and fire—produced by the seasonal changes. Though each has unique traits, they regulate each other. Thanks to these normal climate changes, we experience temperate, hot, cool, cold, and the cycles of growth and storage. Thus, nature’s climate adjusts itself, benefiting all life forms and forming an organic whole. This whole is constantly changing in a regular pattern. Following and utilizing this rhythm maintains dynamic yin-yang balance—beneficial to humans. Breaking this balance leads to disasters. “Humans are born from heaven and earth’s energy” also refers to human origins—derived from heaven, earth, especially the sun’s fire and earth’s water. All life depends on the sun; ultimately, all organisms rely on solar light and heat. Light and heat are Earth’s life sources. Without sufficient light and heat, life cannot emerge or persist. Engels said: “Our planet itself survives only because of solar heat... Without the repelling motion radiated by the sun, all movement on Earth would cease” (*Dialectics of Nature*). Our daily food comes directly or indirectly from plants, as does fuel—both derived from photosynthesis, whose energy originates from the sun. Thus, without the sun, there would be no life on Earth.
|
