Science in Premodern China

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Science in Premodern China

Overview

The study of science in China during the period from 700 to 1449 must be placed within the larger framework of science in premodern China, thus encompassing preceding eras as well. The reason is that, unlike Western history, that of China is not as conveniently divided into "ancient" and "medieval" periods. Moreover, much of the scientific work in China during the age viewed by Westerners as a middle period was in fact on a continuum with that which had occurred in ancient times.

Premodern China saw enormous advances in all realms of science, from medicine to technology, that gave the Chinese enormous advantages over their counterparts in the Western world and, in many cases, the Middle East as well. As with the eras of scientific development in China, the varieties of science practiced in the "Middle Kingdom" must also be seen on a continuum, because Chinese scholars rarely made a distinction, for instance, between "pure" and "applied" science. It is useful, then, to view the various disciplines not so much as discrete entities, but as interlocking circles, an interdependent array of pursuits with astronomy and alchemy—forerunner of modern chemistry—near the center.

Background

Science flourished throughout many phases of ancient Chinese history, and achievements of early Chinese scientists covered a number of areas. At least as early as 1700 b.c., China had entered the Bronze Age, and archaeologists have found Iron Age tools that date back to about 1000 b.c. It appears that by the fifth century b.c., the Chinese had passed on to the next technological stage, making steel from iron.

Around 1500 b.c., Chinese astronomers created a calendar that took into account the phases of the Moon and the length of time it took for Earth to revolve around the Sun—that is, a year. They also recorded eclipses as well as a nova, a star that suddenly grows extremely bright before fading. Their observations of events in space make it possible for historians to be absolutely certain about dates in Chinese history after 840 b.c.

The historic period in China began with the Shang Dynasty (1766-1027 b.c.), which built its power using advanced forms of warfare technology. A Shang chariot squadron consisted of five horse-drawn wagons, each with a driver, an archer, and a soldier bearing a battle axe. In the Shang religion, one can see the elements of an early interest in chemistry. They practiced forms of divination—the study of physical material in order to find omens of the future—using tortoise shells and the bones of cattle or water buffalo. Priests would polish the outsides of the shells or bones, then dig out holes on the inside to make them easier to crack. After this, they applied heat to the underside. As cracks appeared on the top, they would study these cracks much as a palm-reader observes the lines in a person's hand for "omens" concerning his or her future.

Shang farms grew a wide array of crops, and it appears that Shang farmers employed an early form of crop rotation. Mulberry trees on farms in Shang China yielded a product for which China would become famous: silk. Another plant grown on Chinese farms was hemp, important both for ropes and for the narcotic qualities of the plant, which the Chinese used in medicinal treatments. The Shang also developed ice cream—made by mixing milk with soft rice, and then chilling this mixture in snow from the high mountains—in about 2000 b.c.

Shang rulers became increasingly oppressive until they were replaced by the Chou Dynasty (1027-246 b.c.), which maintained power longer than any system in the history of the world. Despite its longevity, the Chou Dynasty was fraught with political upheaval, yet scholarship flourished during the era as well. In 613 b.c., the Chinese made the first recorded sighting of what came to be known as Halley's Comet, which passes by Earth approximately every 76 years. By the fourth century b.c., astronomers in China had compiled a chart showing various stars' locations.

The Chou era also produced China's greatest philosophers, most notably Confucius (551-479 b.c.) and Lao-tzu (500s b.c.). Aside from Confucianism and Taoism, one important school of thought to emerge during this time was Naturalism, which maintained that for every force in one direction, it was right and necessary that there should be a force in the opposite direction. On the one side, there was an active, masculine quality called yang; on the other, an inactive, feminine quality known as yin. The combination of yin and yang, it was believed, produced everything that existed—a concept that would become central to Chinese thought in general, and Chinese science in particular.

Chou rule dissolved into anarchy, leading to the rise of a short-lived but highly significant dynasty, the Ch'in (221-207 b.c.), which gave China the name by which it is known to the rest of the world. The Ch'in ruler Shih Huang-ti (259-210 b.c.) united much of the country for the first time, established China as an empire—it would remain such until 1912—and began the building of the Great Wall. The autocratic Ch'in Shih-huang-ti also built a vast nationwide system of roads and canals, and standardized weights and measures, currency, the written language, and even the size of vehicle axles.

After the Ch'in, which quickly lost power following the death of its founder, the Han Dynasty took power, and would rule for most of the period from 207 b.c.to a.d. 220. Under WuTi (r. 141-87 b.c.), China established the rudiments of the Confucian civil-service system that would remain in place until modern times; issued banknotes; created a state monopoly over industries such as salt-making and iron production; and made its first contacts with the civilizations of the West.

The dissolution of Han rule led to successive periods of crisis and stability that lasted until the founding of the Sui Dynasty (589-618). As had happened before in China, however, political problems did not necessarily impede scientific progress. Thus this era saw developments in the study of medicine, the first use of coal for heat, the first appearance of kites, and the writing of the first encyclopedias. As for the Sui, their rule resembled that of the Ch'in: highly autocratic, short-lived, and historically significant. Also like the Ch'in, the Sui built enormous public works projects, most notably the Grand Canal, a waterway of some 1,000 miles (about 1,600 kilometers) that connected the Yangtze and Yellow rivers.

Impact

During the period that coincided with medieval times in Europe, Chinese scholarship experienced high points under two native-controlled dynasties, both distinguished by reforms and highly efficient governments. The first of these was the T'ang (618-907), which greatly extended the canal network put in place by the Sui, thus aiding the transport of goods from north to south in a land where most major rivers flowed eastward. As the economy of T'ang China thrived, new goods such as tea from Southeast Asia made their appearance. China in turn exported a variety of items, including silk and printed materials.

The latter was an outgrowth of two outstanding Chinese innovations: paper—first developed around a.d. 100 by Tsai-lung (c. 48-118) and not discovered in Europe until the fourteenth century—and block printing, a process whereby a printer carved out characters on a piece of wood. Its invention was attributed to Buddhist monks of the seventh century, who needed copies of sacred texts faster than they could be produced by hand-copying. The world's first printed text was a Buddhist scroll, later discovered in Korea and probably printed in China between 704 and 751. The ink for these early printed documents came from the black substance secreted by burning wood and oil in lamps; later, when this innovation passed to the West, it would incorrectly be called "India ink."

The T'ang Chinese were eager to import knowledge of astronomy and mathematics from India. Indeed, this interest in outside knowledge was a hallmark of the early T'ang, who were more open to "foreign" ideas than most Chinese ruling houses—including the later T'ang. With the growing acceptance of Buddhism that had begun in about the third century a.d., numerous ideas arrived from India, including advances in number theory and the more systematic study of the skies practiced by Indian astronomers at the great center in Ujjain.

Chinese studies in astronomy, however, retained a quasi-religious flavor. As was typical of many premodern societies, there was sometimes little distinction between astronomy and astrology, and all work was heavily controlled by the state. An edict of the emperor in 840, for instance, stated that, "If we hear of any intercourse between the astronomical officials or their subordinates and officials of other government departments or miscellaneous common people, it will be regarded as a violation of security regulations which should be strictly adhered to." Nonetheless, it was still possible to make significant advances in such an environment, as the building of a water-driven astronomical clock in 721 attests. This was the creation of the Buddhist monk I-hsing and the military engineer Liang Ling-tsan, and it was the first known instrument to use an escapement, a device essential for regulating a clock's movements.

A humiliating military defeat by the forces of the Abbasid caliphate at Talas marked the watershed of the T'ang Dynasty, which steadily dwindled over the next 15 decades until China fell into a period of semi-anarchy identified by Chinese historians as "Five Dynasties and Ten Kingdoms." Finally, in 960 the establishment of the Sung Dynasty, which would last until 1279, brought order to the country.

Astronomical study flourished under the Sung Dynasty, which saw the building of an even more impressive astronomical clock than the 721 T'ang model. In 1077 Su Sung, a diplomatic envoy to the court of a "barbarian" ruler to the north, was embarrassed to discover that his host's calendar was more accurate than that of his own emperor. Therefore he requested and received permission from the emperor to build what he called a "heavenly clockwork," an astronomical clock powered by a water wheel.

Science historian Daniel J. Boorstin described Su Sung's impressive creation as "a five-story pagoda-like structure. On the topmost platform, reached by a separate outside staircase, was a huge bronze power-driven armillary sphere within which there rotated automatically a celestial globe.... Every quarter-hour the whole structure reverberated to bells and gongs, the splashing of water, the creaking of giant wheels, the marching of manikins." It was altogether a far more accurate time-keeping device than anything that would appear in Europe for many centuries, but after a new emperor took the throne in 1094, his court declared the previous ruler's calendars to be inaccurate—a custom of Chinese rulers. Thus the clock was allowed to fall into disrepair.

Sung astronomers also advanced Chinese methods of time-keeping by replacing the 10-day week with a 7-day version—based on the four phases of the Moon—in about 1000. Along with their counterparts in Arab lands, astronomers of this era witnessed a supernova, an exploding star, in 1006, and again in 1054. The first of these remained visible for a year, and the second—the first such event for which relatively detailed records exist—was described by Chinese and Japanese astronomers as the sudden appearance of an extremely bright light in the constellation known by Europeans as Taurus. Much later, during the Ming era, Chinese astronomers in 1433 would observe a comet also noted by the Italian Paolo Toscanelli (1397-1482).

Though the Sung were highly competent administrators, they lacked savvy in foreign affairs, and a disastrous alliance with the nomadic Juchen people of Manchuria forced them to move their capital to southern China in 1127. Nonetheless, the Southern Sung period was a time of tremendous scientific and technological advancement.

Notable during this period, for instance, were the geological studies of Chu Hsi, who in his Chu Tsi Shu Chieh Yao (c. 1175) suggested that fossils were once living organisms. Chinese astronomers in about 1270 built a torquentum, an instrument for making transformations between spherical coordinates. An improvement on the armillary sphere, it was the first such device to use an equatorial mounting.

Porcelain-making also reached its height during this era. Though porcelain's invention had been attributed to the semi-legendary figure Tao Yue (c. 608-c. 676), who combined the "white clay" or kaolin of the Yangtze River banks with other types of clay, it is likely that the craft actually began to take shape as early as the third century a.d. Not until the eighteenth century would Europeans develop means of making porcelain.

On the high seas, the magnetic compass made navigation at sea much easier. Land compasses, which used a naturally magnetic piece of lodestone, had been used in China as early as the fourth century b.c., but in the period between 850 and 1050, the needle compasses had been developed for use at sea. These took into account the shift in Earth's magnetic field, or magnetic declination. Though a description of a magnetic compass first appeared in European writings in about 1190, it would not be until the fifteenth century that Europeans became aware of the magnetic declination.

Along with the compass, improvements in shipbuilding enabled the Sung to send ships (junks) on merchant voyages. The larger Sung junks could hold up to 600 sailors, along with cargo. Around this time—to judge from a church carving that dates to 1180—Europeans began to use a ship's rudder, but this invention, too, had long existed in China. As early as the first century a.d., Chinese shipbuilders had used rudders in place of the more cumbersome steering oars.

Tea and cotton emerged as major exports during the Southern Sung era, while a newly developed rice strain, along with advanced agricultural techniques, enhanced the yield from China's farming lands. China also exported a variety of manufactured goods, including books and porcelain, while steel production and mining grew dramatically. Banks and paper money—one of Sung China's most notable contributions—also made their appearance.

The development of movable-type printing aided the spread of information: instead of carving out a block of wood, a printer assembled precast pieces of clay type to ink out written messages. This, one of the most significant developments in Chinese technology, is attributed to the alchemist and blacksmith Pi Sheng, who in c. 1045 cut a series of characters into clay cubes on an iron frame, making a solid block of type. Ultimately, however, the peculiarities of the Chinese language would encourage the use of block printing over movable type. It is easy enough to store and use blocks when a language has a 26-letter alphabet, as English does; but Chinese has some 30,000 characters or symbols, meaning that printing by movable type was extremely slow. Thus movable-type printing would have its greatest impact in Europe, where it was introduced by Johannes Gutenberg (c. 1395-1468) in about 1450.

Great strides in science and technology continued right up to the end of the Sung era, making the end of the Sung Dynasty all the more of a tragedy. The Sung created pumps for lifting water, and experimented with water power as a means of operating silk looms and cotton mills. The final years of Sung rule saw the development of one of history's most significant inventions, one that would completely alter the world of the future: the use of gunpowder for warfare.

Gunpowder, actually invented about 950, is counted along with paper, printing, and the magnetic compass as one of the four most significant discoveries made by the premodern Chinese. Here the connection between alchemy, chemistry, and technology in Chinese science is most clear. Alchemy had existed in China from ancient times, long before European alchemists began attempting to turn base metals into gold, but in China it was more closely tied to another elusive goal: the quest for immortality. Thus it naturally allied itself with medical study, which in China—as witnessed by the development of acupuncture in ancient times—often tended to venture into fields that are not fully encompassed by scientific understanding.

Long before the Sung era, Chinese alchemists had been experimenting with the properties of saltpeter and sulfur as a means of creating an elixir for immortality, and between 350 and 650 they produced numerous chemical concoctions involving these substances. By about 850, however, when a Taoist text warned against the dangers of mixing these substances, it had become apparent that the elixir was more likely to end life than to prolong it. Around 1040, Tseng kung-liang, building on the saltpeter-and-sulfur experiments of previous Chinese chemists, created the world's first formula for gunpowder. His was merely combustible, however, and not explosive; nonetheless, its military applications were clear, and it quickly gained use in flame-throwers. By the thirteenth century, Sung chemists had learned how to make explosive gunpowder.

As for firearms themselves, archaeological digs in Manchuria have uncovered a small gun, dating from c. 1288. The first European depiction of a gun—one that fired arrows instead of metal balls—dates from four decades later, in 1327, and it is likely that elements of this technology had arrived in Europe from China. During the last days of the Sung Dynasty, scientists were experimenting with rockets, which they used in warfare against the Mongols.

Impressive as these new forms of military technology were, however, they did not prevent the onslaught of the Mongols, who established China's first foreign ruling house, the Yüan (1264-1368). Under the rule of Kublai Khan (1215-1294), contact between East and West increased dramatically, leading to visits by outsiders such as Marco Polo (1254-1324), who brought back to Europe information about Chinese advances such as gunpowder, paper money, the compass, kites, and even playing cards.

Yet the Chinese chafed at rule by "barbarians," and were only too happy to see the overthrow of the Yüan Dynasty by the Ming (1368-1644), China's last native-born ruling house. The Ming emperor Yung-lo (r. 1403-24) sent a number of naval expeditions under Admiral Cheng Ho (c. 1371-c. 1433) to India, Ceylon, Yemen, and even Africa. These ships brought with them such Chinese luxuries as silks and porcelains, and returned bearing exotic animals, spices, and varieties of tropical wood. Centuries later, when archaeologists unearthed the ruins of Zimbabwe in Africa, they found broken pieces of Ming porcelain.

The naval expeditions were costly, and this fact brought them to an end; also expensive was the establishment of a vast palace complex. In 1421, when Yung-lo moved the capital from Nanjing in the interior to Beijing, he built a palace 5 miles (8 km) in circumference. Containing some 2,000 rooms where more than 10,000 servants attended the imperial family, it was not so much a palace as a city: hence its name, "Forbidden City," meaning that only the emperor and the people directly around him were allowed to enter. Built to illustrate the boundless extent of Ming power, the Forbidden City became—aside from the Great Wall—the best-known symbol of China in the eyes of the world.

These ventures, along with the restoration of the Grand Canal (which had fallen into disrepair under the Mongols), placed heavy burdens on the treasury and weakened the power of the Ming. So too did attacks by Chinese, Korean, and Japanese pirates on Ming merchant vessels, not to mention the appearance of European traders who were often pirates themselves. The Ming Dynasty would continue for several centuries before falling to Manchurian invaders, but like many Chinese ruling houses that preceded it, it experienced a long, slow period of decline.

Likewise, China itself, home to many of the world's great advances in science and technology, began to lag in comparison to the once-technologically inferior civilizations of the West. Just as Europe was awakening from the long sleep of the Dark Ages, China began to turn inward, and Chinese scholars and political leaders placed increasing emphasis on tradition rather than progress, order rather than experimentation. In the nineteenth century, the decaying Chinese monarchy would pay heavily for its reaction against change, and the country was beleaguered by outsiders, including not only Europeans and Americans, but Japanese. Only in the late twentieth century did China again begin to emerge as a formidable technological and scientific power.

JUDSON KNIGHT