Today is the spring equinox of the twenty-four solar terms. The vernal equinox is one of the earlier established solar terms of our ancestors and has a definite astronomical significance. On this day, the sun shines directly on the equator, "day and night are divided and cold and summer are flat", day and night are equally long, hot and cold are balanced, and the spring equinox is also the "midpoint" of spring.
"The spring rain shocks the spring valley days, and the summer is full of mango and summer and summer are connected. Autumn dew autumn frost falls, winter snow snow winter small cold. "Among the catchy twenty-four solar terms, the twenty-four Chinese characters represent the wisdom of the Chinese nation that has lasted for thousands of years.
Two festivals a month, about 15 days apart each other, each solar term has three phenology... Twenty-four solar terms cut a "solar return year" evenly into almost equal lengths of 24 parts. According to this scientific "timetable", the ancient Chinese people rationally and effectively arranged a year's agricultural activities and daily life, and developed a deep traditional culture related to the solar terms.
When did the twenty-four solar terms originate, and what kind of development did it undergo before it was finally determined? What is the guiding value of the twenty-four solar terms for the production and life of the ancients? From ancient times to the present, which has lasted for thousands of years, why do the twenty-four solar terms have a sustained influence? The surging reporter interviewed Bi Xuling, director of the Folklore and Intangible Cultural Heritage Research Office of the Institute of Literature of the Shanghai Academy of Social Sciences, to deeply interpret this intangible cultural heritage of mankind.
Screenshot of the countdown to the 24 solar terms at the opening ceremony of the Beijing Winter Olympics, picture from: People's Daily
【Dialogue】
Originated from primitive astronomical observations, the Han Dynasty was finalized
The Paper: What is the process of the twenty-four solar terms from origin to final formation?
Bi Xuling: The twenty-four solar terms originated from the original astronomical observation, its history can be traced back to prehistoric society, in many Neolithic cultural sites have been excavated and excavated with sun patterns, moon patterns, constellation patterns of faience pottery, ancestors also created the sun and moon myth as the representative of the celestial myth, preserved in the "Classic of Mountains and Seas" and other early documents.
The result of the original astronomical observations was that the ancestors summed up some experience of perceiving the changes of the four seasons by observing the changes in the starry sky, such as the knowledge of the direction of the Big Dipper's handle to indicate the four seasons. But this knowledge is not fine enough, the practicality is not enough, so later the ancestors focused on the sun, found that as the sun moves, the shadow of the object will also move accordingly, and invented the oldest astronomical instrument - Gui Watch. Gui is a ruler placed horizontally, the watch is an upright pole, through the combination of gui and the table can measure the length of the noonday sun shadow. By counting the cyclical changes in the length of the noonday sun shadow, the ancestors first established the two solar terms of the twenty-four solar terms, the summer solstice (the shortest sun shadow) and the winter solstice (the longest sun shadow). They also determined the length of a regression year by measuring the winter solstice moments of two adjacent years.
From observing the starry sky to inventing the gui table, the ancients' astronomical observation rose from intuitive perception to the use of tools, which is a great progress. With the invention and use of the Gui watch, for a long time, the accuracy of regression years measured in ancient China was at the highest level in the world.
At the closing ceremony of the Beijing Winter Paralympic Games, the 24 solar terms reappeared with Chinese elements such as the tiangandi branch hour. Image courtesy of People's Daily
On the basis of the winter solstice and the summer solstice, the ancestors further subdivided the solar terms, established the "two points" (spring equinox, autumn equinox), and later added the "four stands" (li chun, li xia, li qiu, li dong), so far, the main trunk of the twenty-four solar terms, the four o'clock and eight festivals, have appeared, which is something that has been completed in the pre-Qin period.
In the Qin and Han Dynasties, with the continuous progress of astronomical observation methods, the ancients, on the basis of measuring the shadow of the sun, divided the solar ecliptic (the orbit of the sun in the imaginary celestial sphere) by 24 equal parts, so that each solar term had an accurate control angle on the ecliptic, thus fully grasping the relationship between solar terms and the operation of the sun, and the twenty-four solar terms were finalized. In the Han Dynasty's Huainan Zi, the full name of the twenty-four solar terms has appeared.
The Paper: The traditional mainland calendar is a yin-yang calendar, is the part of the solar calendar reflected through the twenty-four solar terms?
Bi Xuling: "Yin-Yang Calendar" is a calendar that combines the solar calendar and the lunar calendar.
The solar calendar (referred to as the solar calendar) is a system of knowledge constructed by the ancestors on the basis of observing the laws of the sun's operation. The calendar common to most countries, regions and peoples in the world is the solar calendar. The solar calendar of ancient Egypt is the earliest solar calendar formed in the West, and after being modified, it has become the common "Gregorian calendar" in the world today. China's twenty-four solar terms are also the solar calendar.
The lunar calendar (abbreviated as the lunar calendar) is a more intuitive calendar based on the cycle of moon phase changes. The ancestors called a cycle of the moon fullness "synodic moon", the day when the moon could not be seen in the late period was called "synodic day", which was set as the first day of each month; the day with the fullest moon was called "looking at the day", which was set as the fifteenth day of the month. From Shuo to Wang to Shuo is a month in the lunar calendar.
The lunar calendar has a much longer history of use than the solar calendar. The two have different advantages and disadvantages. The solar calendar (solar calendar) can be used to record the evolution of the cold and heat, seasons, climate, phenology and agricultural periods of the year, but in each month, the synodic, looking, and two strings of the moon cannot be seen; the lunar calendar is mainly used to record the month and day periods, and the people in the coastal areas can also judge the tidal date and time according to the lunar phase of the lunar calendar. However, the lunar calendar does not consider the earth's movement around the sun, so that the change of the four seasons has no fixed time in the lunar calendar and cannot reflect the seasons.
Around the end of the Xia Dynasty, the ancestors had already used the lunar calendar and the solar terms together to form the yin-yang calendar. The yin-yang calendar is a fusion of the cycles of the Earth, moon, and sun. The month is based on the lunar operating cycle, the length of the year is based on the sun's return year, and the leap month is to make the month and the four seasons of cold and heat match, which has a strong practicality and has been used to this day.
A "timeline" for scientifically guiding production-life practices
The Paper: Many people think that the names of the twenty-four solar terms are very beautiful, and if you look closely at these names, they are all-encompassing, some reflect the seasons, some reflect the length of day and night, some reflect precipitation, some reflect temperature changes... What is the basis for integrating these things into one to form a solar system?
Bi Xuling: The basis for the formulation of the twenty-four solar terms is the annual visual movement of the sun (the year of the sun's return). How is the annual visual movement of the sun observed? The ancients introduced a hypothetical, concentric but much larger celestial sphere in observing the trajectory of celestial bodies, all of which operated on the celestial sphere. The Sun's orbit on the celestial sphere is called the ecliptic, and the position of the Sun is represented by the ecliptic coordinate system. The starting point of the zodiac coordinate system is the vernal equinox, on this day the sun illuminates the equator vertically, which is stipulated to be 0 degrees of ecliptic longitude, after which the sun runs every 15 degrees for a solar term, and the 24 solar terms run exactly 360 degrees, at which time the sun returns to the vernal equinox and completes a return to the year of movement.
The "Lichun" fireworks at the opening ceremony of the Beijing Winter Olympics. Image courtesy of People's Daily
The movement of the sun determines the changes in the seasons, climate and phenology on the earth, so when naming the twenty-four solar terms, the most obvious changes and characteristics of the seasons, climate and phenology will generally be selected for naming, such as lichun, lixia, liqiu, and lidong reflect the changes in the seasons, the small summer, the big summer, the small cold, the big cold reflect the change in temperature, and the rain, valley rain, light snow, and heavy snow reflect the changes in precipitation, such a name is the most easily understood, and it is also particularly suitable for guiding the practice of production and life.
The Paper: How are the twenty-four solar terms used to guide farming?
Bi Xuling: Agricultural cultivation is actually a way of labor that obtains the means of production and living by acting on natural objects (soil, plants), so its success or failure often depends on whether it can accurately grasp the laws of nature. The twenty-four solar terms reflect the changing laws of the seasons, temperatures, animals and plants in nature, so the most important application of the twenty-four solar terms in ancient China is to guide agricultural production practices. The first chinese calendar, the Han Dynasty's Taichu Calendar, officially included the twenty-four solar terms in the calendar, which was promulgated by the central government to various localities to guide agricultural production.
Most of the twenty-four solar terms have corresponding agricultural arrangements. For example, although the Spring Festival is the most obvious reflection of the change of the seasons, there is a proverb that "at the end of the year of Lichun, planting land is calculated early", which means that from the beginning of Lichun, we must make a plan for spring ploughing. Another example is the rain festival, although it mainly shows the change of precipitation, but there is also a farmer proverb that says: "Rain has rain crops are good, and big spring and small spring are a treasure." "It means that if there is rain on this day, it indicates that the crops can have a good harvest, which provides a reference for farmers to further strengthen field management."
The Paper: It is said that the 24 solar terms are the product of the observation of the sun by the ancestors of the Yellow River Basin, and the natural phenomena corresponding to the solar terms and the time point of agricultural activities are closer to the climate of the Yellow River Basin. In fact, China is a vast country, and the temperature and climate vary greatly from north to south, but it seems that from the Yellow River Basin to the Yangtze River Basin to the southwest ethnic minority areas, the impact of the 24 solar terms on the mainland is far more than the Yellow River Basin. In China, where the climate is very different, can everyone use the 24 solar terms to arrange a year's agricultural activities?
Bi Xuling: The twenty-four solar terms are mainly summed up by the ancestors of the Yellow River Basin in the process of engaging in agricultural production activities for a long time, but it can basically reflect the changes of seasons and climate, and it is convenient to arrange agricultural activities according to this, so it is gradually extended to the whole country. That is to say, the twenty-four solar terms are a credible schedule, and the time between each of the two solar terms, as well as the laws of the sun's movement, are clear.
Although the climatic and phenological changes in the northeast, southwest, Lingnan and other regions are inconsistent with the Yellow River Basin because of China's vast territory, people in different regions can still flexibly use the timetable of the 24 solar terms in light of the actual local conditions.
Festivals overlap with the festivals and become an important part of traditional culture
The Paper: Some "festivals" have also become "festivals", such as the Qingming Festival. In some areas of the north, there is also a saying that "the winter solstice is greater than the year", and the winter solstice is still regarded as a very important festival. In the mainland traditional festival system, what is the position of the twenty-four solar terms? What are the important folk customs around the twenty-four solar terms?
Bi Xuling: Most of the formation of traditional Chinese festivals is related to solar terms, and some of them directly originate from a certain solar term. An important reason for the overlap between solar terms and festivals is that the ancestors were concerned about the impact of seasons and climate change on human production and life, and some important solar terms have been specially addressed as festivals.
For example, the "Standing" of Lichun means the beginning and arrival, symbolizing vitality and prosperity, and the people should be greeted with joy, so Lichun was once the first festival of the new year. According to records, Zhou Tianzi would lead princes, princes, doctors, etc. to hold a spring ceremony on the spring day to pray for a good agricultural harvest. The upward and downward effects soon developed into a social festival.
The "solstice" of the winter solstice is the meaning of the pole, the so-called extreme of things must be reversed, the ancients believe that the cold winter after the winter solstice will gradually warm up, so the winter solstice is regarded as an important turning point in temperature and seasons for ten days, in order to remind the people to pay attention to the rhythm of production and life, adjust to the timing, but also the winter solstice as a festival to live. In the Zhou Dynasty, the winter solstice day was to hold a ceremony to sacrifice the gods and ghosts of heaven and earth. In the Han Dynasty, the official governments at all levels held a solemn celebration ceremony on the winter solstice, a hundred officials to celebrate, the people to rest the city, and prepare new clothes, prepare food, worship the ancestors, with a strong festive atmosphere.
It should be said that the festival and the festival overlap, carrying more different regions, different eras of faith taboos, food customs, celebration and entertainment and other aspects of humanistic connotations, has become an important part of traditional culture, passed down to this day.
The Paper: The earliest of the twenty-four solar terms to be determined is the "two to" and "two points", these four time nodes are more intuitive, that is, the longest and shortest day and night of the year, the day and night are equally long. In addition to China, there are also observations and determination of these time points in other civilizations, but why did our ancestors continue to expand on this basis to form a unique twenty-four solar terms system?
Bi Xuling: The eventual formation of the twenty-four solar terms system in China is mainly related to the fact that traditional Chinese culture has continued to this day, and it is also related to the fact that ancient China was a traditional agricultural country. Because civilization continues, the accumulation of astronomical calendars is profound, and through continuous improvement and verification, the twenty-four solar terms are finally formed. Because agriculture is the mainstay, the state attaches importance to the formulation of calendars that can guide agricultural production, and promulgates them throughout the country by state administrative acts.
Other civilizations, on the other hand, either did not have enough time to continue to explore solar terms, or did not have such a high degree of dependence on agriculture, so they did not form a relatively complete solar system to guide agricultural production. For example, the ancient Babylonians also determined the winter solstice, summer solstice, spring equinox, and autumn equinox relatively early, which is based on a summary of the laws of the sun's movement, but the ancient Babylonian kingdom was sometimes invaded by foreign enemies and eventually perished, and many astronomical and calendar attempts were forced to be interrupted.
The Paper: The twenty-four solar terms guide farming in an agricultural society, and rely on this to carry a lot of cultural meanings. Nowadays, with urbanization, agriculture is getting farther and farther away from the lives of urban people, and even with the improvement of scientific forecasting meteorological level, agriculture no longer relies on the guidance of the twenty-four solar terms. Are the twenty-four solar terms, as our precious intangible cultural heritage, in danger of weakening in contemporary times? Will the next 24 solar terms still be an important link that unites our culture?
Bi Xuling: The twenty-four solar terms have been passed down and used for thousands of years. Although China is no longer an agricultural country, the twenty-four solar terms, as an agricultural guidance knowledge system, still have certain reference and inheritance value for contemporary agricultural production.
The twenty-four solar terms are not a pure knowledge system for agricultural guidance, but also carry traditional Chinese scientific knowledge, philosophical cognition, aesthetic concepts, etc., which is a large and complex system that deserves in-depth study and understanding.
In the long history of development, the twenty-four solar terms have become a common cognitive and cultural system of the Chinese nation, condensing the ethical feelings, life consciousness, aesthetic tastes and beliefs of the people of all ethnic groups in China, and is the link and glue to enhance the awareness of the Chinese national community. The idea of the unity of nature and man, which is contained in the twenty-four solar terms, which respects nature, imitates nature, loves nature, uses nature, and supports nature, is the essence of Chinese culture, which has important universal significance and shared value at a time when the global ecological environment is deteriorating and sustainable development is in crisis.