As the native religion of China, Daoism (also spelled Taoism), together with Confucianism and Buddhism, comprises the main body of traditional Chinese culture. Daoists, in pursuit of the ideal of becoming immortals by practicing Dao, made great efforts to transcend conventional wisdom about life and knowledge and so helped both to define ancient science in China and to advance it through a great number of inventions.

Relationship between Daoism and science

For a long time, many Western translators, writers, and scholars misunderstood Daoist thought, largely overlooking its scientific and proto-scientific aspects. Moreover, different understandings of what constitutes science have rendered the issue more confusing. While some scholars denied any link between Daoism and science, many studies have confirmed an important relationship between them. Daoist thought is basic to Chinese science and technology. Daoism provided a philosophical foundation for the development of science; its love for nature, its conception of change, its unique mastery of the relationship between human beings and nature, and its pursuit of freedom are based on the exploration of nature. Daoist admiration for ancient scientific inventors, and their absorption of science and technology in history, show that Daoism tried to reach its religious ideal by means of science. In addition, Daoism’s cultural structure is favorable for science. The unique Daoist ideal of material immortality is invaluable in stimulating the observation and exploration of nature and life, and the development of techniques of alchemy, medicine, and related fields.

Daoists regard Dao as the origin of all things, including human beings, and they believe that people can return to Dao and thus attain immortality. Because immortality can be acquired through learning, one’s life rests with oneself rather than heaven. Daoist scriptures include such sayings as “Probe into the mystery of heaven and earth and understand the root of creation” (The Taoist Canon, Vol. 18, p. 671). In fact, such explorations serve the goal of achieving oneness with the Dao, which leads to becoming an omniscient and almighty immortal, a True Human of True Knowledge.

Unrealistic as immortality is, many Daoist ideas, techniques, and practices for longevity are reasonable and scientific. They constituted the most important part of Daoist spiritual heritage in the Middle Ages. Thus, Joseph Needham argues in Science and Civilization in China (1956) that Daoism “developed many of the most important features of the scientific attitude, and is therefore of cardinal importance for the history of science in China” (vol. 2, p.161). Similarly, Welch Holmes writes in Taoism: The Parting of the Way (1957) that “the Daoist movement has sometimes been called the Chinese counterpart of Western science … To a large extent the Daoists practiced experimental science” (p.134).

Daoist contributions to science

Hua Tuo, a famous Daoist doctor in the third century C.E., was the first to use a type of anesthesia called ma fei san. He also formulated the gymnastic techniques called wu qin xi (imitation of five-animal playing) for nourishing vitality of life. A text of Daoist prescription Zhou Hou Bai Yi Fang (Collection of prescriptions for hundred-and-one diseases fourth century C.E.), written by Ge Hong and enlarged by Tao Hongjing, contains the first known record of the disease of smallpox. It also records therapeutic techniques for dealing with a variety of acute medical conditions, including artificial respiration, bleeding stoppage, abdominocentesis, catheterization, clyster, intestinal anastomosis, débridement (sore cleaning), drainage, fracture treatment with superficial fixture, and disjointed articulation restituting. Remarkably, this work recorded an anti-malaria treatment using southernwood (Artemisia annua L.). In the 1970s, scientists extracted artemisinin from southernwood, which is a significant discovery in the history of antimalaria treatments from medicines of the quinoline category.

Sun Simiao, a great Daoist doctor, summed up in the seventh century C.E. the prevention of struma by using animal thyroid and the prevention of nyctalopia by using animal livers. And the treatment of restituting mandible disjointing that Sun Simiao put forward is still in use in modern medicine. Jin Si Xuan Xuan (The incredible mysteries in the golden box), a Daoist text of parasitology written sometime between the fourteenth and seventeenth centuries C.E., enumerated a “Catalogue of Nine Parasite Species” with illustrations of various kinds of parasites, as well as figures depicting their life cycles. In seeking elixirs from the bodies of human beings themselves, Daoists made great strides in the field of biochemistry. Both Joseph Needham and Lu Gwei-Djen hold that the medicine named qiushi, which was made by medieval Daoists, is a relatively pure preparation of urinary steroid hormones. A similar medicine was made in the West by a German biochemist in the early twentieth century.

Daoists also acquired solid knowledge of certain chemical reaction processes. They accurately described the reversible reactions between mercury and thiosugar. Long Hu Huan Dan Jue (The oral formula for cyclically transformed elixir of dragon and tiger), written by Jin Ling Zi, an expert in alchemy in the Tang Dynasty (618–907), recorded precise methods of making arsenic-copper alloy and of extracting pure copper, methods developed by Daoists over many generations. Instead of conforming to an older Daoist tradition of keeping key links secret or of using obscure terminology, this text clearly and definitely states strict rules of operation that are similar to those of modern chemistry.

As the basic components of gunpowder in ancient China were niter, sulfur, and carbonaceous substances, all frequently used in Daoist alchemical experiments, the invention of gunpowder can be traced back to Daoist writings in the Han Dynasty (206 B.C.E.–220 C.E.). The formula included in Bao Pu Zi Nei Pian (The inner chapters of the Philosopher Master-Who-Embraces-Simplicity), written by Ge Hong in the fourth century C.E., already covered the basic composition of gunpowder. In the middle of the ninth century C.E., the Daoist scripture Zhen Yuan Miao Dao Yao Lue (Classified essentials of the mysterious Tao of the true origin of things) clearly recorded the precise composition of gunpowder. Obviously, the time of its invention was much earlier.

Many Daoists were also metallurgists. The hydrometallurgical technique of smelting copper from cupric sulfate liquor was first used in China in Daoist alchemic practices. It can be traced back to Huai Nan Zi (The book of Master Huainan), a Daoist text written in the early years of the first century C.E., it formally appeared in Daoist texts of the Tang Dynasty, and it became the prevailing technique of copper production during the Song Dynasty (960–1279). It was no later than the Song Dynasty that Daoists had identified the element arsenic and extracted pure samples of it. Around the year 550 C.E., a Daoist practitioner invented a technique of steel production called guan gang fa, by which pig iron and wrought iron were heated together to a certain temperature for higher quality steel. With its moderate carbon content, this kind of steel was ideal for making high-quality tools. This technique was widely used and refined in China during the succeeding one thousand years.

With seven kinds of materials, Daoist alchemists created the earliest fireproof sealing material called six-one mud. They made glass and preserved valuable technical data in their writings. They wrote works on casting techniques such as Shen Xian Lian Dan Dian Zhu San Yuan Bao Zhao Fa (Spot casting methods of bronze mirror of the three origins of things by the immortals), in which they recorded in detail the techniques of quality control in casting. Ever since Huai Nan Zi in the Han Dynasty, Daoists used mercury-tin alloy and later added lead amalgam to create an ideal media for bronze mirror polishing.

A technique involving the suspending of magnetized needles was used by Daoists to test the quality of lodestone, which was a major healing object in alchemy. Eventually, this technique led to the invention of the magnetic needle compass. In addition, modern scientists found that Wu Yue Zhen Xing Tu (Maps of the true topography of the five sacred mountains), drawn in the third or fourth centuries C.E. and treasured by Daoists over the last eighteen centuries, contains the earliest type of contour map. The maps roughly reflect the local terrain and routes of the mountains.

Precise clock devices are of great importance in Daoist practices. Throughout Chinese history, many Daoists participated in the invention and improvement of the water clock. The famous cheng lou, a scale-controlled water clock invented by a Daoist named Li Lan, was widely used in the 400 years between the fifth and eighth centuries C.E., and served as an important component of various types of compounded clock devices in China. It was also used in the medieval Islamic world; studies show that Muslims probably learned about such clocks from the Chinese. Daoists of the Quanzhen Sect even invented portable water clock devices. A scripture called Quanzhen Zuo Bo Jie Fa (Quanzhen Sect easy preparation for sitting quiet in meditation), written between the tenth and fourteenth centuries C.E., recorded the technical details of making, debugging, and controlling the clocks.

Zhang Zhihe, a Daoist who lived during the Tang Dynasty, expounded the phenomenon of duration of vision, as it was called in modern optics. Later, another Daoist, Tan Qiao, who lived during the Five Dynasties (907–960), discussed the phenomenon of reflection of plane mirrors. Zhao Youqin, a Daoist of the Quanzhen sect who wrote the famous scientific work Ge Xiang Xin Shu (New Book on the Investigation of Astronomical Phenomena) in the Yuan Dynasty (1260–1368), conducted a series of large-scale experiments on geometric optical problems, such as rectilinear propagation of light, hole imaging, and intensity of illumination. He came to correct conclusions in these fields two centuries earlier than Galileo Galilei (1564–1642).

His rough conclusion that “illumination intensifies as the intensity of light source enhances, but decreases as the image distance increases” appeared four hundred years earlier than Lambert’s formula of qualitative illumination published in 1760, according to which “illumination is in reverse proportion to distance squared.” In the early years of the nineteenth century, there were still Daoist believers in Guangzhou who studied with an open mind both the traditional Daoist theory of sphere-heavens and modern European astronomy.

In order to avoid losses in their alchemical experiments and for many other religious purposes, Daoists conducted weather observation and forecast. Their scripture Yu Yang Qi Hou Qin Ji (The near forcasting of the weather of rain or fine) analyzed scientifically the causes of wind and rain and recorded in terse but vivid verses their observations, which conform with modern meteorological science. They even provided various types of “cloud pictures” in the text.

Daoists not only explored but also wanted to navigate the heavens. The “flying vehicle made of jujube heart timber,” recorded by Ge Hong in his Bao Pu Zi Nei Pian and regarded as the earliest design for a propeller aircraft, reveals the Daoist knowledge of the aerodynamic principles of flight. Modern scientists have recreated the vehicle according to Ge Hong’s records and testified it to be technically reasonable. Ge Hong added that when rising to a height of forty li (about 12.44 miles) into the heavens, one can reach the outer space of taiqing (super clarity), where the air is powerful enough to support flying objects, helping them to fly naturally by inertia instead of motive forces.

This is close to the law of First Cosmic Velocity in the modern science of astronautics. In the fourth century C.E., a hermit Daoist named Wang Jia wrote Shi Yi Ji (Record of gleaning), in which he claimed that once there had been a huge space aircraft named Cha ridden by the immortals. This aircraft used the sea as its base for launching and landing, and it continually navigated around the four seas, making a circuit every twelve years.

With the invention of gunpowder and the subsequent emergence of applied techniques for the control of its explosive power, the idea arose of using it as a rocket propellant. In the fifteenth century, an official of the Ming Dynasty named Wan Hoo conducted and died in the first attempt at manned rocket flight in human history—propelled by forty-seven gunpowder rockets. A Daoist biographical text formally printed in 1909 includes a description of a Daoist beauty who launched her aircraft into the heavens from a silo by means of a propellant compounded from cyprinoid fat.

Daoists were responsible for rich scientific achievements in many other fields, including cosmology, uranography, calendar making, geography, geology, mineralogy, botany, zoology, pharmaceutics, architecture, porcelain production, dye making, wine making, zymurgy, cerebral science, acoustics, wushu, sex hygiene, strategics, and psychology.

Because the impetus for scientific exploration comes for Daoists from their religious belief in immortality, their science was inevitably bound by the ideas, purposes, and the historical development of Daoism. Therefore, it was impossible for science to gain an independent and deep development within the Daoist framework. Yet the remarkable achievements of Chinese science were also enabled and inspired by the Daoist interpretation of reality.