Solar terms are inseparable from the four seasons.
Twenty-four solar terms are to divide the annual position change of the sun on the ecliptic (360 circumference) into 24 equal parts, with an interval of 15, and every time the sun advances 15 is a solar term. There are 24 solar terms in a year 12 months, and each solar term is about 15 days. The change of the position of the sun will inevitably lead to the evolution of the ground climate, so the "qi" of solar terms has the meaning of meteorology and climate.
The 24 solar terms originated from the ancient people in China who looked up at the astronomical phenomena and looked down at geography. Many countries in the world have solar terms, but only China has formed a complete 24 solar terms. Taichu calendar is a symbol of the formation of the ancient calendar system in China, which was named after the implementation of the first year of Emperor Wu of the Han Dynasty. It is characterized by taking silver moon as the first month, bringing the 24 solar terms into the calendar for the first time, taking beginning of spring as the beginning of the 24 solar terms and Li Si (beginning of spring, Changchun, beginning of autumn and beginning of winter) as the beginning of each season. Every season has six solar terms.
It should be noted that the 24 solar terms are mainly astronomical, while the division of the four seasons in the meteorological sense is not uniform. In meteorology, the first day when the average daily temperature is above 10 for five consecutive days is called entering spring. Therefore, taking the northern part of China as an example, although the solar term has arrived in beginning of spring, it is still often cold in spring, and beginning of spring in our life is not as warm as spring, so we should "cover our clothes". This is because the 24 solar terms refer to the four obvious seasons in the middle and lower reaches of the ancient Yellow River and some Yangtze River basins. However, China is a vast country with great differences between the north and the south, so it is impossible for its climate to be consistent with that of the Yellow River Basin.
20 16 1 1, 24 solar terms declared by China are listed in UNESCO's representative list of intangible cultural heritage of mankind, which not only guides agricultural production, but also plays an important guiding role in people's daily health care.
One of the functions of solar terms is to adjust the relationship between man and nature.
Solar terms reflect the ancients' understanding of the changing laws of the four seasons, climate and phenology in a year. Season has the meaning of season. The climatic characteristics of solar terms should conform to their seasonal climatic characteristics, that is, the temperature is high in spring, hot in summer, cool in autumn and cold in winter. For example, the solar terms such as midsummer, intense heat, slight cold in winter and severe cold clearly reflect the seasonal climate characteristics. From the point of precipitation, the autumn solar terms such as spring rain, Grain Rain, White Dew, Cold Dew and First Frost also clearly reflect the precipitation characteristics of the season where the solar terms are located.
The division of solar terms is closely related to the sun, and the influence of the sun on nature is self-evident. Therefore, the change of solar terms will inevitably lead to the change of natural phenology. For example, fright means the day when God wakes up a dormant animal with thunder. "Guanzi Situation Solution" holds that: "Spring is the beginning of Yang, so everything is born. When the sun rises in summer, everything grows. Autumn begins in the shade, so everything is harvested. In winter, everything is hidden because of the exhaustion of Yin qi. Therefore, spring and summer growth and autumn and winter collection are also the festivals of the four seasons. " As one of the things in nature, human daily life and diet are bound to be influenced by the four seasons. For example, people often sleep more in winter and fall asleep early, but they often sleep less in summer than in winter, and often sleep late and get up early, which is the biological characteristics of people.
Solar terms have natural attributes, and the most basic function is to adjust the relationship between man and nature. Through the establishment of the four seasons, people can adapt to the natural time sequence for production and life.
"correspondence between man and nature" is the core view of TCM health preservation
Chapter 25 of the Tao Te Ching states the relationship between man and nature in this way: "The old road is big, the sky is big, the land is big, and the king is big. There are four in the domain, and Wang Juyi is one of them. Man's law is based on the earth, the earth is based on the sky, the sky is based on the Tao, and the Tao is natural. " One of its meanings is the correspondence between man and nature and the harmony between man and nature. "Harmony between man and nature" is also the core view of TCM health preservation. Huangdi Neijing, a classic of traditional Chinese medicine, points out: "Man and the qi of heaven and earth coexist, reaching at four seasons" and "Man is related to heaven and earth, corresponding to the sun and the moon", which shows that man and nature are a whole, and man is influenced by the four seasons of nature. It is healthy to adapt to the changes of natural solar terms, otherwise it may be that "the five internal organs are infected with each other when they are in the absence", which shows the influence of solar terms on human pathology.
Wind, cold, heat, humidity, dryness and fire are six normal natural climates, which are called six qi. The change of seasons and solar terms produces six qi, which is the condition for the growth of all things and is harmless to normal human body. The imbalance of solar terms and excessive or insufficient six qi make the six qi a pathogenic factor and an evil of six evils, which has a negative impact on human health. The ancient astronomical work "Kaiyuan Zhan Jing" recorded the diseases caused by the abnormal solar terms: "beginning of spring, before the arrival, the soldiers will rise, the wheat will not work, and malaria will emerge; If you don't, you'll be sick and shriveled at most. Rain, dry before it arrives, immature wheat, pain; If you don't get it, you will get sick. " A similar exposition on the pathogenicity of the 24 solar terms is also recorded in Yitong Guayan. Not everyone will be attacked by the evil of six evils when the solar terms are abnormal. If people can always keep in good health and adapt themselves to the external climate change in time, the impact of seasonal solar terms disorder will be very small. The so-called "virtual evil steals the wind and sometimes avoids it."
In addition to the evil of six evils, the human body itself is out of control, and "taking wine as a pulp" and "unrestrained life" will also lead to premature aging. Combined with the characteristics of modern people's daily life, under the influence of multiple factors such as work pressure and excessive entertainment, irregular life seems to have become the norm for many people, especially those living in big cities. With the emergence of more and more sub-health and even sick people, there is a trend of youthfulness. In view of this, it is necessary to emphasize following the laws of nature, conforming to the four-season solar terms, and running through the whole process of TCM health preservation with the concept of correspondence between man and nature and unity of man and nature.
Regarding the principles to be observed in daily health preservation, Huangdi Neijing gives the answer: "The four seasons of cold and heat should be appropriate, anger should be harmonious, and yin and yang should be both rigid and soft." It is proposed that nature should adapt to the changes of the four seasons and solar terms, flirt with ambitions, live cautiously, and combine yin and yang. Huangdi Neijing emphasizes the four-season health care from the perspective of seasonal health care, and gives the specific methods of four-season health care, such as "spring and March, which means getting old ... lying at night and getting up early, striding around the court and slowing down to make life". Besides, it also gives the health preserving methods of Xia San in the month, autumn and winter, involving daily life, mood, exercise, diet and so on. The principle of "nourishing yang in spring and summer and nourishing yin in autumn and winter" is the key to adapt to the changes of yin and yang in four seasons, which is also the truth of "eating radish in winter and ginger in summer". In this way, we can "keep the righteousness inside, and evil can't be done."
(Author: Zhang Cong, Associate Professor, School of Traditional Chinese Medicine, Beijing University of Chinese Medicine)
(Guangming Daily)