Since Chinese archaeologists discovered remains of two rice fields from some 10,000 year ago in the Yangtze River Basin in the 1990s, increasing data have shown that East Asia, where China is located, is the cradle of early human agriculture, just like West Asia, where barley and wheat were domesticated about 10,000 years ago. Domestication of crops evidenced that ancient Chinese people already had a farming calendar.
Rites of Zhou: The Artificers’ Record, a 2,000-year-old work on bureaucracy and organizational theory, recorded in detail how Chinese people determined the time for farming. They set up a pole for measurement vertically on the flat ground and used the cardinal point of the pole as the center to draw a circle. At sunrise, the pole shadow and the circle intersect at a point. At sunset, they intersect at a different point. By connecting the two points, people drew a line pointing due east one way and west the other. Connecting the central point of this east-west line to the cardinal point of the pole will make a north-south line. The directions could be further adjusted at night by observing Polaris.
In the mid-latitudes of the Northern Hemisphere, at noon, when the sun is at its lowest point in the sky and the shadow of the pole is the longest, it marks the arrival of winter solstice. The shortest shadow indicates the summer solstice. Through observations over the years, the length of a solar year could be determined with accuracy, and an agricultural calendar was formulated to guide farming activities.
In this observation system, the pole and the circle drawn with its cardinal point as the center together resemble the shape of the Chinese character “中,” which means “center” or “middle.” This system has exerted a profound influence on the axial symmetry of ancient Chinese cities, with the central axis of Beijing during Yuan (1271-1368), Ming (1368-1644), to Qing (1644-1911) dynasties as representative.
According to Rites of Zhou, when the first ruler of the Zhou Dynasty (1046-256 B.C.) established the state, he had to determine its geographical location. Because time could only be measured through space, when the king built a capital, he had to first decide the place and direction of the city. He needed to establish a connection between the royal court and the central axis of the city which symbolizes the source of power. The Forbidden City, which was home to Chinese emperors in Ming and Qing dynasties and constructed on the central axis of Beijing, demonstrates the significant influence of the ancient philosophy.
Great importance was attached to the direction of due north and south in astronomical observation activities in ancient China. The Book of History, which was believed to be compiled by great Chinese thinker and educator Confucius, claimed that legendary Chinese Emperor Yao requested his men determine the time of winter solstice, summer solstice, spring equinox, and autumn equinox by observing astrology. The north-south line was the most important observation axis.
Contrasting ancient Chinese people, Europeans found a sense of time by observing the motion of the sun. Marcus Vitruvius Pollio, a Roman architect and engineer from the first century B.C, wrote in The Ten Books on Architecture that the east-west direction was most important. He explained that it was because people needed to observe the stars accompanying the sun at sunrise and sunset. Thus, the Parthenon, a temple on the Athenian Acropolis, Greece, was built facing east.
Chinese people used east and west to determine the time of spring equinox and autumn equinox. On the days of spring equinox and autumn equinox, the sun rises due east and sets due west. Huainanzi, a Chinese philosophical classic from the Western Han Dynasty (202 B.C.-25 A.D.), recorded the method for observing the motion of the Big Dipper. On the day of spring equinox, the Big Dipper points due east at dusk. On the day of autumn equinox, it points due west.
I found in 2016 that by connecting the Altar of the Sun, a venue in eastern Beijing where emperors of Ming and Qing dynasties offered sacrifices to the God of the Sun on spring equinox, to the Altar of the Moon, a place in western Beijing where emperors worshiped the God of the Moon on autumn equinox, you get an east-west line traversing across the old city proper. This line and the city’s north-south central axis meet at the Hall of Supreme Harmony Square in the Forbidden City, forming the classic horizon coordinate system in ancient China for determining winter solstice, summer solstice, spring equinox, and autumn equinox.
Thus, it is clear that the old city of Beijing contains abundant time-honored cultural information and showcases the basic methods ancient Chinese people used to determine time and space. The central axis of Beijing represents the essence and quintessence of agricultural culture with a history of nearly 10,000 years in East Asia.
The central axis of Beijing has roots dating back to the planning and design of Dadu City in the Yuan Dynasty around the 13th century. When the Mongols founded the Yuan Dynasty and conquered all of China, the Yuan emperors planned this axis to show determination to inherit and carry on Chinese culture. At the northern end of this axis, two grand structures, the Drum Tower and the Bell Tower, were built in commemoration of legendary Emperor Yao’s abdication in favor of Emperor Shun. This was a major event for the integration of the Mongolian ethnic group and other Chinese ethnic groups. Several centuries later, the Manchus founded the Qing Dynasty and made Beijing the capital. They also proudly inherited this axis and integrated into the bigger family of the Chinese nation.
In this sense, the central axis of Beijing witnessed the development and growth of China as a unified multi-ethnic country. It demonstrates the immortality of ancient China in the form of unique culture. The core of Chinese civilization never changed with a change of rulers. Ancient Chinese culture is incredibly inclusive, which serves as an important reason for the continuous development of Chinese civilization to this day.