Dongxiwen·Spring Festival of the Year of the Dragon｜Yang Xiaoping: Why does the Taichu Calendar fixate the first month of Mengchun as the "beginning of the Yuan Dynasty"?

　　Editor's note:

　　The Jade Rabbit bids farewell to the old year, and the Golden Dragon welcomes the New Year. Among the twelve Chinese zodiac signs, the dragon is the only fictitious mythical animal; in traditional Chinese culture, the dragon is a symbol with unique meanings.

　　The Year of the Dragon is approaching. China News Service's "East-West Question" has launched a series of "Spring Festival of the Year of the Dragon" planning series since February 6. From the origin of the dragon in Hongshan culture to the evolution of the dragon in the Dunhuang Grottoes, from more than a hundred years Explore the cultural flavor behind the Spring Festival in the Year of the Dragon from how foreigners celebrated the Spring Festival in the past to why Chinese people at home and abroad are called "descendants of the dragon." Please stay tuned.

　　China News Service, Langzhong, Sichuan, February 9th: Why does the "Taichu Calendar" always regard the first month of Mengchun as the "beginning of the Yuan Dynasty"?

　　——Exclusive interview with Yang Xiaoping, Vice President of Sichuan Luoxiahong Research Association and Professor of West China Normal University

　　China News Service reporter He Shaoqing

　　The Spring Festival is the beginning of the new year of the lunar calendar and evolved from the ancient rituals of praying for good luck at the beginning of the year. Although the custom of celebrating the Spring Festival in China has lasted for thousands of years, there was no uniformity before the Han Dynasty as to which day was the "beginning of the Yuan Dynasty". During the period of Emperor Wu of the Han Dynasty, astronomers such as Luo Xiahong compiled the "Taichu Calendar", which always started with the first month of Mengchun. The date of the Spring Festival was thus fixed and continues to this day.

　　What reforms did the Taichu Calendar make to the ancient Chinese calendar? Why does the "Taichu Calendar" always use the first month of Mengchun as the beginning of the year? What are the similarities and differences between the lunar calendar originating from China and the Gregorian calendar originating from the West? Yang Xiaoping, vice president of the Sichuan Luoxiahong Research Association and professor at West China Normal University, recently accepted an exclusive interview with China News Service's "East-West Question" to explain this.

Video: [East-West Question] Yang Xiaoping: Why does the "Taichu Calendar" fixate the first month of Meng Chun as the "beginning of the Yuan Dynasty"?

Source: China News Network

The interview transcript is summarized as follows:

China News Service reporter: When did the Spring Festival originate? What are the differences in the dates and names of the Spring Festival in the past? When did China take the first month of Meng Chun as the "beginning of the Yuan Dynasty"?

Yang Xiaoping:

Due to the lack of documents from ancient times, it is difficult to directly verify the origin of the Spring Festival. Some people believe that the Spring Festival originated from the activities of worshiping gods and ancestors at the beginning and end of the year during the Yin and Shang Dynasties in China (December Festival). Another view is that the Spring Festival originated from Yu and Shun. Shun became the emperor and led his men to worship heaven and earth. From then on, people regarded this day as the beginning of the year and the first day of the first lunar month.

　　Although the Chinese people have a long-standing custom of celebrating the Spring Festival, the word "Spring Festival" was not used frequently in ancient times. It mostly means "Spring Festival" in the meaning of "spring", which is quite different from the modern meaning of "Spring Festival". For example, "It's the Spring Festival, so it's hard to stop a good trip" (You Miao, Song Dynasty's "Poetry of the Tang Dynasty, Wang Qi"), "Three days before the Spring Festival, Jiangxiang is in the New Year" (Song Dynasty, Wen Tianxiang, "Twenty-Four Days").

On January 22, 2023, the first day of the Lunar New Year, the Miao people of Fenghuang Ancient City in Xiangxi, Hunan, paraded in the ancient city in costumes. Photo by Yang Huafeng

　　The term "Spring Festival" in the modern sense actually means "the beginning of the Yuan Dynasty", which is the beginning of the year. This concept and meaning also have different names in different dynasties. In the Pre-Qin Dynasty, it was called "Shangri", "Yuanri", "Chanisui", "Xiansui", etc., and in the Han Dynasty, it was called "Three Dynasties", "Suidan", "Zhengdan" and "Zhengri". etc. In the Wei, Jin, Southern and Northern Dynasties, it was called "Yuanchen", "Yuanri", "Yuanshou", "Suichao", etc.; in the Tang, Song, Yuan and Ming dynasties, it was called "New Year's Day", "Yuan", "Suiri", "Xinzheng", "Xinyuan", etc.; in the Qing Dynasty, it was called "New Year's Day". "Yuan Day", the month in which the Spring Festival is located is called "Yuan Yue".

　　Which day is the beginning of the year, and the dates in the past dynasties are inconsistent. The Xia Dynasty used the first month of Meng Chun as the beginning of the year, and the Shang Dynasty used the twelfth month (twelfth month) as the beginning of the year. After Qin Shihuang unified the six kingdoms, he established the "Zhuanxu Calendar" and used ten months as the beginning of the year. The early Han Dynasty continued to use the Qin calendar.

A collector in Henan displays the "Star Mirror" from the Han Dynasty. Photograph with caution

　　Due to the increasing errors in the Zhuanxu Calendar, in the first year of Yuanfeng in the Western Han Dynasty (110 BC), Emperor Wu of the Han Dynasty ordered Sima Qian, Hu Sui and others to discuss reforming the calendar. The compilation of the new calendar took six years. In 104 BC, Emperor Wu of the Han Dynasty adopted the Taichu Calendar compiled by Deng Ping, Luo Xiahong and Tang Du after comparison. The "Taichu Calendar" takes the first month of Mengchun as the first month of the year, and stipulates that the month without Zhongqi is a leap month.

　　The "Taichu Calendar" ran for 188 years and was replaced by the new calendar. Almost every dynasty in China has revised its calendar, and new calendars are constantly appearing. However, these calendars only make time more accurate, but they all retain the "Taichu Calendar" with the first month of Mengchun as the beginning of the year, the method of setting leaps, and the time of the twenty-four solar terms.

　　After the Revolution of 1911, Sun Yat-sen asked the Ministry of the Interior to compile and print a new almanac in the "Order of the Provisional President on the Promulgation of Almanacs". Later, it was stipulated that January 1 of the Gregorian calendar is the "New Year", but it is not called "New Year's Day".

　　When Yuan Shikai came to power, there were two calendar systems in China, one was the Gregorian calendar derived from the West, and the other was the traditional Chinese lunar calendar. In 1914, Zhu Qiqian, the Minister of Internal Affairs of the Republic of China, named the Lunar New Year's Day as the Spring Festival, the Dragon Boat Festival as the Summer Festival, the Mid-Autumn Festival as the Autumn Festival, and the Winter Solstice as the Winter Festival in the "Four Season Holidays". He reported it to the President and was approved. From then on, January 1 of the Gregorian calendar was called "New Year's Day", and the first day of the first lunar month was called "Spring Festival". The Lunar New Year appeared as the Spring Festival.

On January 17, 2020, the armillary sphere was the main lantern at the "Langyuan Xianpa" Spring Festival Lantern Festival held in Langzhong, Sichuan. Photo by Wang Lei

China News Service reporter: When did the Chinese calendar originate? What reforms did the Taichu Calendar make to the ancient Chinese calendar? Why does the "Taichu Calendar" always use the first month of Mengchun as the beginning of the year?

Yang Xiaoping:

As one of the four ancient civilizations, Chinese astronomy can be traced back to the Neolithic Age, 8,000 to 7,000 years ago. Archaeological evidence such as the Beidou star map at the Xishuipo site in Puyang, Henan shows that the ancestors at that time had established a relatively systematic space-time system and an early model of the heaven, earth and universe, and initially formed such as the twenty-eight constellation star observation system and the four-image system. , the theory of the sky-covered universe and other important concepts in traditional astronomy.

　　Astronomy was the basis for the preparation of legislation. According to legend, before the "Taichu Calendar", China had the "Huangdi Calendar", "Xia Calendar", "Yin Li", "Zhou Calendar", "Lu Li" and "Zhuanxu Calendar", which are called the Six Ancient Calendars. However, due to the lack of documentation, it is impossible to accurately verify the origin of these calendars.

　　"Taichu Calendar" is China's first scientific calendar handed down from generation to generation with complete written records and physical data to be tested. It not only always takes the first month of Meng Chun as the "beginning of the Yuan Dynasty", but also incorporates the twenty-four solar terms into the Chinese calendar for the first time.

　　The twenty-four solar terms are unique to the Chinese calendar. It is based on changes in the Earth's position along the ecliptic, the Earth's orbit around the Sun. Each solar term corresponds to a certain position that the earth reaches on the ecliptic for every 15° movement.

On January 20, 2024, "The Beauty of the Years—The Essence Exhibition of the Twenty-Four Solar Terms of Cultural Relics from the Tianjin Museum" was launched at the Tianjin Museum. Photo by Tong Yu

　　Festival and Qi are two different concepts. Before the Shang Dynasty, China had four climatic conditions: the vernal equinox, the autumnal equinox, the summer solstice and the winter solstice. During the Shang Dynasty, the ancients divided the length of each Qi into two and created the four festivals of Beginning of Spring, Beginning of Summer, Beginning of Autumn and Beginning of Winter. The system of twenty-four solar terms has been basically formed during the Warring States Period. In 104 BC, Luo Xiahong corrected the order of solar terms to make the astronomical calendar more suitable for agricultural production seasons.

　　The reason why the "Taichu Calendar" can always use the first month of Mengchun as the beginning of the year is because Chinese civilization is rooted in agricultural civilization. Farming pays attention to spring sowing, summer planting, autumn harvest and winter storage. Using October as the beginning of the year or the beginning of winter as the beginning of the year are quite different from production and life. Using the first month of Mengchun as the beginning of the year is more in line with the needs of agricultural production.

Reporter from China News Service: Why was Luo Xia Hong called "the most brilliant constellation in the history of astronomy" by Joseph Needham, a famous British historian of science and technology?

Yang Xiaoping:

Luo Xiahong invented the "Tongqi rate" in the process of compiling the calendar. This algorithm for approximating fractions is called "Luo Xiahong's algorithm" by modern scholars because it is close to the "continued fraction-progressive fraction" method in the modern mathematical sense. ”, which can be said to have been a great inspiration to Zu Chongzhi’s “Zui Shu Qiu Yi Shu” in the Southern and Northern Dynasties and Qin Jiushao’s creation of “Dayan Qiu Yi Shu” in the Southern Song Dynasty.

On January 18, 2024, the "Spring Festival Old Man" sent blessings to tourists in Langzhong Ancient City. Because Luo Xiahong compiled the Taichu Calendar, China's first complete calendar with written records, and incorporated the twenty-four solar terms into the calendar for the first time, he was also known as the "Spring Festival Old Man". Photo by Zhang Lang

　　Luo Xia Hong formed the "Luo Xia Hong System" based on a series of innovations in systematic observation, mathematical algorithms, and logical structures. The "Luoxia Hong System" is often compared with the "Ptolemaic System" constructed by the ancient Greek astronomer Ptolemy in the 2nd century AD.

　　Ptolemy improved the "geocentric system" of his predecessors to form an astronomical system. The "Ptolemaic system" was influenced by Plato and Aristotle, valued partial analysis, and believed that a system composed of spheres and circular orbits was perfect. The "Luo Xia Hong System" is influenced by Taoism and naturalism, attaches great importance to overall synthesis, and believes that converting various periods into integers is perfect.

　　Among the ten major achievements in the development of Eastern and Western astronomy in Luo Xia Hong's era summarized by Joseph Needham, Luo Xia Hong accounted for three of them - including compiling the "Tai Chu Calendar", proposing the "Huntian Theory", and inventing the "Tongqisu". Therefore, Luo Xia Hong was also called "the most brilliant constellation in the history of astronomy" by Joseph Needham.

On January 18, 2024, Langzhong folk flower shoe performance was held. Photo by Zhang Lang

　　To commemorate Luo Xia Hong's astronomical achievements, on September 16, 2004, with the approval of the International Astronomical Union's Small Celestial Object Nomination Committee, the National Astronomical Observatory of the Chinese Academy of Sciences named an asteroid with the international permanent number 16757 "Luo Xia Hong Star".

China News Service reporter: What are the similarities and differences between the lunar calendar originating from China and the Gregorian calendar originating from the West?

Yang Xiaoping:

The Gregorian calendar, the calendar commonly used in the world today, originated in ancient Egypt more than 6,000 years ago. The ancient Egyptians discovered that there were approximately 365 days between floodings of the Nile River. At the same time, they also discovered that one morning every year, when the tide of the Nile reached Cairo today, Sirius and the sun rose from the horizon at the same time. Based on this, the ancient Egyptians defined a year as 365 days, divided into 12 months with 30 days per month, and added 5 days as festivals at the end of the year. This was the Egyptian solar calendar.

On February 4, 2024, the beginning of the Spring Festival, in Zhongmatun, Xiakuo Village, Rongshui Town, Rongshui Miao Autonomous County, Liuzhou City, Guangxi, villagers peeled the cane shells while cutting sugar cane. China's agricultural production is closely related to the 24 solar terms. Photo by Long Tao

　　China's current lunar calendar is a combination of the lunar calendar and the solar calendar. The lunar calendar is based on the changing cycle of the moon phases. Each lunar phase changes to one month, and the solar return year is the length of a year. Twenty-four solar terms and leap months are added to make the average calendar year compatible with the return year.

　　Comparing the Western Gregorian calendar and the Chinese lunar calendar, we can see that there are many differences in timing between the two. For example, the Gregorian calendar divides the 365 days in a year into twelve months, while the lunar calendar divides the year into ordinary years and leap years. There are twelve months in an ordinary year. There are thirteen months in leap years. This is because the starting point of the compilation of the Chinese lunar calendar is to serve agricultural production. In some years, one month will be added to ensure that the lunar calendar corresponds to the actual seasons. The Gregorian calendar is mainly compiled based on the results of astronomical observations.

　　In addition, because the earth's rotation is uneven and gradually slows down, the earth's orbit around the sun is not uniformly circular. The movements of the sun and moon are constantly changing, so time is also constantly changing. In fact, no calendar can remain unchanged forever, and both Eastern and Western calendars need to be constantly adjusted.

　　As humans gain a deeper understanding of the laws of the universe, the calendar we use today will continue to be improved and perfected in practice. The changes in the Eastern and Western calendars are also the epitome of the continuous advancement of human astronomy, mathematics, and physics.

Expert profile:

　　Yang Xiaoping, PhD in literature, postdoctoral fellow in historical philology, academic and technical leader of Sichuan Province, vice president of Sichuan Luo Xia Hong Research Association, deputy director of Sichuan Luo Xia Hong Research Center, and second-level professor of West China Normal University. Study exegesis, "Three Kingdoms", Dunhuang manuscripts, Ming and Qing manuscripts, dictionary compilation, common words and idioms, new words and new idioms, etc. Hosted the National Social Science Fund's "Research on Vulgar Words in Qing Dynasty Manuscripts", "Research on Vulgar Words in Qing Dynasty Handwritten Documents", the Ministry of Education's Youth Project "Research on New Chinese Words from 1912 to 1949", key projects of the State Language Commission, and Sichuan Provincial Philosophy Society Planning Key projects, key projects of the University Ancient Committee.