Western science developed according to naturalistic thinking

To my understanding, in ancient times Greek philosophers proposed different views about nature in terms of naturalistic thinking in the tradition of Logos. Perhaps influenced by Hesiod's Theogony, which presents a genealogy of the gods originating from one primordial god, Thales of Miletus (fl. 6th BCE) started naturalistic thinking by regarding water as the archai of many natural phenomena. He not only created a sensation in philosophy, but also a new way of thinking in natural philosophy or science.

Aristotelian natural philosophy and his idea of science

Based on the reasoned discourses of the Pre‐Socratic philosophers and Plato, which describe natural phenomena in terms of statements or propositions, Aristotle (384–322 BCE) developed his natural philosophy by synthesizing earlier views of nature and establishing the two‐sphere model of the cosmos, that is, with both Earth and Heaven as spherical domains (tian yuan di yuan 天圓地圓; Lindberg , 42f., 90f.). The cosmos is depicted as a great sphere, divided and demarcated into terrestrial and celestial regions. It is geocentric and contains concentric spheres. Within its inner or terrestrial region, the natural place for the motionless Earth was at the center of the universe, surrounded by water, air, and fire. In the celestial region, there were seven “wandering stars,” that is, Moon, Mercury, Venus, Sun, Mars, Jupiter, and Saturn. The fixed stars beyond those seven wandering stars were made up of ether and were considered eternal and unchanging (Lindberg , ch. 3; see Figure ).

Chinese Depiction of Aristotle's Two‐Sphere Model of the Cosmos.

Aristotle also worked out the first system of logic in the Organon, in which he presented his idea of science and the explanatory structure of demonstrative knowledge in the Posterior Analytics. The most perfect scientific knowledge is a proof through the proper, immediate, or true cause or reason for a fact or an effect. He thus used mathematical proof as his model to define true knowledge as deductive demonstration. Such deductive demonstration comes from principles, axioms, definitions, or hypotheses with premise(s) to explain phenomena, prove conclusions, and describe or predict the position of wandering stars.

In Aristotle's classification of the sciences, there are theoretical and practical sciences. Theoretical sciences include natural philosophy, mathematics (including astronomy), and metaphysics. Practical sciences have something to do with human choice or behavior, such as politics, ethics, and economics. Each science has its own principle. Natural philosophy, a branch of theoretical sciences, is thought to be totally different from politics, ethics, and economics.

Under the influence of Aristotle's idea of science, Euclid (fl. 300 BCE) synthesized earlier mathematics into his Elements, and Claudius Ptolemy (c. 90–c. 168 CE) did the same for astronomy in his Almagest. Based upon Aristotle's natural philosophy—especially the two‐sphere model of the cosmos—Ptolemy established Western astrology in his Tetrabiblos, emphasizing celestial influence on the terrestrial earth and humans.

Comets as a normal phenomenon in the sublunar region

In the Meteorologica, Aristotle used his idea of the natural motion of four elements to explain hundreds of natural phenomena within the terrestrial region. Comets are one of the normal phenomena in this terrestrial region.

Before the seventeenth century, comets had not been recognized as stars with regular periods moving around the sun. Since comets appear outside of the zodiac, they could not be wandering stars like the Moon, Mercury, Venus, Sun, Mars, Jupiter, or Saturn. Aristotle believed that comets were an atmospheric phenomenon, originating from dry, warm exhalations of oily air that emanated from the earth, naturally moving toward the Moon, and igniting near the region of fire (Heidarzadeh , ch. 1). Thus, comets were explained as a normal phenomenon in the terrestrial region in Aristotle's natural philosophy (see Figure ).

Comet as a Normal Phenomenon in the Terrestrial Region.

Natural theology

In the second century, Christianity spread over the territory of the Roman Empire. Since ancient times, the book of Genesis in the Old Testament has been closely associated with the Christian religion and science in Western civilization. How could theologians explain that the Lord created the physical universe, living things, and Adam within six days? They had two choices at that time. One was to study nature by themselves, and the other was to borrow from pagan Platonic or Aristotelian natural philosophies. The early church fathers chose the latter (Lindberg ).

In the late Middle Ages, when Christianity became dominant in Western culture, the Aristotelian cosmology had been integrated with a Christian theology of Genesis as a Christianized Aristotelian worldview. Nature became the work of the Creator. It was thought that one may understand the Creator by way of his creation. This view became natural theology, a branch of learning by which to know the Creator. The Creator was seen as the most remote cause for the creation of the cosmos. Later, natural theology encouraged seventeenth‐century “scientists” to pursue the natural laws to glorify the lawmaker, the Creator.

Chinese science developed by associative or correlative thinking

It seems to me that the ancient Chinese looked to nature not for the sake of Nature itself. For example, Yung Sik Kim points out that mutual association “was a key mode of explanation in Chu Hsi's discussion of natural phenomena,” “the ‘natural’ world … was frequently invested with moral qualities” (Kim , 315f). In Kim's opinion, Chu Hsi 朱熹 (or Zhu Xi), a prominent Neo‐Confucian scholar of the Song Dynasty, was not concerned with nature itself; rather his interest was political and social. Derk Bodde () also finds that ancient Chinese posited a moralistic view of nature.

Analogy and the Way (Dao)

Scholars who have paid attention to ancient Chinese thought and Greek philosophy have found that the former emphasized Dao and the latter Logos. I will take tian yuan di fang 天圓地方 and tian yuan di yuan 天圓地圓 as examples to show that Dao and Logos are two different ways of expressing the relation of Heaven and Earth in these two natural philosophies. In contrast to tian yuan 天圓 representing the circular motion of celestial stars and di yuan 地圓 representing the spherical shape of the Earth, ancient Chinese thinkers understood nature in terms of analogy and according to Dao. By means of analogy, Confucius (孔子 551‐479 BC) and his student Tzeng Zi or Tzeng Shen (曾參 505–435 BCE) expressed their understanding of tian yuan 天圓 as tian dao 天道 representing the way of the heaven and di fang 地方 as di dao 地道 representing its way of rest in order to encourage gentlemen to imitate their example by following their spirit, rather than learning them mindlessly as geometrical figures of the heaven and earth (Gao , “Tzengzi Tian Yuan Di Wushiba 曾子天圓第五十八,” 207). It reflects the Confucian emphasis on the relation of Heaven and human beings (tian ren guan xi 天人關係). Later, tian yuan 天圓 and di fang 地方 were used in a political context to represent jun dao 君道 (way of the emperor) and chen dao 臣道 (way of the courtier) respectively. Finally, tian yuan di fang 天圓地方 appeared in the Zhou Bi Suan Jing 周髀算經 (The Arithmetical Classic of the Gnomon and the Circular Paths of Heaven), a work concerning the circular paths of heavenly bodies and the measurement of the cosmos; thus the idea of tian yuan di fang 天圓地方 gets its mathematical and physical meanings(Hsu ).

The natural philosophy of qi

In 2000, Yung Sik Kim used the term “Natural Philosophy” to express Chu Hsi's natural knowledge in The Natural Philosophy of Chu Hsi (1130–1200) in terms of the “Theory of Ying Yang, Five Phases, and Qi” (yinyang wuxing qi lun 陰陽五行氣論). I propose that there is also a Chinese natural philosophy of qi, which has been modified, adjusted, and enriched through different times or ages up until the present.

The character 氣 (气 or 炁 qi) represents one of the most influential concepts in Sinic culture. Before the late nineteenth century, Chinese people believed that qi was the most fundamental substance composing everything in the cosmos, including material things, the human body, mind, or spiritual soul. One can find the character 氣 (qi) in works on Chinese philosophy, medicine, astrology, military strategy (bingshu 兵書), literature, subject‐based reference books (leishu 類書), almanacs (tongshu 通書), geomancy (fengshui 風水), and so on. I will focus on my understanding of the Chinese natural philosophy of qi and its implications from a comparative viewpoint of the history of science. One can say that Chinese culture is a kind of culture of qi with many ideas expressed in terms of qi, including fields of natural knowledge or so‐called science.

According to the natural philosophy of qi, everything, including heaven, earth, the myriad of things, human beings, and so on is composed of qi, which moves everywhere in the cosmos. Thus, qi was seen as the most fundamental reality for Chinese in ancient times. I call this perspective the “Realism of Qi” (Qi Shizhai Lun 氣實在論), a phrase I coined.

As for the cosmogony of the world, or how the universe and the myriad of things are formed by qi through yin/yang and wuxing (five phases), Chinese literati usually took for granted that the universal dynamic qi will spontaneously form the visible things as we see them without offering any detail. Thus, I call this perspective “Natural Qi‐ism,” (Ziran Qi Lun 自然氣論), another term I coined.

According to the imagination of Christian culture, the omnipotent Creator created the world by natural laws in six days. Likewise, according to the imagination of the Sinic culture of qi, the universal dynamic qi constantly moves and constitutes all the things we see. Compared with the Creator as first and final cause, we may say that Natural Qi‐ism stresses the “efficient cause” of the universal dynamic qi.

Ren qi 人氣: qi issued from human beings

Among the different kinds of qi, qi that issues from people has been noted since ancient times.

According to the system of militarism employed in the Warring States Period (475–221 BCE), in order to know the fate of the country, two kinds of qi that issued from human beings were recorded and emphasized. There was one qi that issued from the battlefield (戰場之氣). For example, we find the following precept in Mozi's Ying Di Ci (墨子.迎敵祠 Sacrifice Ritual during Encounter with the Enemy):

凡望氣, 有大將氣, 有小將氣, 有往氣, 有來氣, 有敗氣, 〔有勝氣,〕能得明此者可知成敗、吉凶。

Watching the physical form of qi above the camp of the enemy, appearing there are qi issued from admirals, young militants, withdrawing troops, coming troops, defeated troops, [victor's troops]. One who can comprehend those above‐mentioned qi will win and succeed and make the opponent lose and fail. (Mozi ).

Another form of qi is that issued from the emperor. The Yi Si Zhan 乙巳占 (Astrology Published in the Year of Yi Si [656]), published by Li Chun‐Feng 李淳風 (602–670 CE), collects earlier Chinese astrological records of the above‐mentioned two kinds of qi that issue from people. It contains one chapter concerning qi that issues from the emperor and ten chapters related to qi that issues on the battlefield (Li , juan 9, 147–60).

In addition, in the culture of qi, ancient Chinese developed a special astrology in terms of a special kind of “bad qi” (li qi 沴氣) produced by humans on the Earth's surface, which was thought to bring disasters including rising up toward the stars, resulting xing zhan yi xiang 星占異象 (anomalous astrological phenomena).

Wuxing Xiangli Zhi Qi 五行相沴之氣

Beside the “mutual generation theory of the five phases” (五行相生) and the “mutual restriction theory of the five phases” (五行相剋), there exists a view of wu xing xiangli zhi qi 五行相沴之氣. Li qi 沴氣 is a kind of ominous qi, resulting from the different clashes of the “five phases” and causing different disasters in nature. According to the imagination of natural philosophy of qi, the emperor's misbehavior or judgment caused different kinds of li qi. In his commentary on the Documents (Shangshu 尚書), one of the classics of Confucianism, Fu Sheng (伏勝 260–161 BCE) points out that, in the manner of ruling the court, if the Emperor does not respect his leading courtiers with a positive attitude (貌之不恭), follow their good suggestions (言之不從), distinguish between good and bad officials (視之不明), like to hear true opinions (聽之不聰), or make intelligent judgments (思之不睿), there will rise five wuxing xiangli zhi qi: jin li mu 金沴木 brings the damage of mu qi 木氣; mu li jin 木沴金 causes the damage of jin qi 金氣; shui li huo 水沴火 will damage huo qi 火氣; huo li shui 火沴水 does harm shui qi 水氣; jin, mu, shei, huo li tu 金木水火沴土 means qi of 金木水火 together reduces tu qi 土氣. By way of correlative thinking, the above‐mentioned five kinds of li qi correspond to the following five kinds of disasters, such as xylon ice (雨木冰), nine sacred tripods shaking (九鼎震), ice nil (亾冰), heavy rain, snow, or hail‐storms (大雨、大雪、雨雹), and earthquake or landfall (地震、山崩) respectively recorded in the Spring and Autumn 春秋. There is another kind of li qi which is most serious and reflects the “relations between human beings and heaven” (ren tian guan xi人天關係). If the emperor makes all five mistakes, then comes qi of jin, mu, shui, huo, tu li tian 金木水火土沴天, which means ominous qi of jin, mu, shui, huo, tu will move together upward to the heaven and cause serious anomalous astrological phenomena such as comets and lunar or solar eclipses recorded in the Spring and Autumn 春秋 (Hsu ).

Similar to the early Western church fathers, who chose to borrow pagan Platonic or Aristotelian natural philosophies rather than study nature themselves, Han Dynasty Confucians like Dong Zhongsu (董仲舒) chose to borrow the view of wu xing xiangli zhi qi 五行相沴之氣 rather than investigate nature on their own (Dong ). In contrast to the relationship between science and Christianity, Dong Zhongsu and other Confucian literati borrowed the view of wu xing xiangli zhi qi 五行相沴之氣 to reflect the negative relations among politics, ethics, and nature as a means of limiting the absolute power of the emperor.

The encounter of two traditional sciences

Matteo Ricci (利瑪竇1552–1610 CE), the most famous Jesuit missionary in late Ming China, learned about Chinese natural knowledge from his interactions with Chinese literati. At the same time, he introduced Western learning into China. In doing so, he facilitated an encounter between Chinese and Western sciences, such as the Jesuit view of air versus the Neo‐Confucian view of qi (Hsu ), the four elements theory versus the five phases view, the Western view of the Earth as a sphere versus the Chinese view of the Earth as a square, and Chinese astrology versus Western astrology, as well as different explanations for solar and lunar eclipses, the generation of hail, comets, and so on.

A comparison of two traditional sciences

The transmission of Western learning by Ricci and other Jesuits had a great impact on some Chinese literati, who used Western learning as a reference to make an evidential study of traditional natural knowledge. Xiong Mingyu (熊明遇, 1579–1649 CE) was a good example. He wrote A Draft on Regularity (Ze Cao 則草) and A Draft on the Investigation of Things (Ge Zhi Cao 格致草) in which he distinguished two new approaches to traditional texts, reliable texts of traditional natural knowledge with evidence (Ge Yan Kao Xing 格言考信), and doubtful texts of traditional natural knowledge without evidence (Miao Lun Cun Yi 渺論存疑). Xiong was thus the pioneer of the seventeenth‐century evidential study of Chinese natural knowledge. Based upon Western learning of Aristotelian natural philosophy, he regarded ominous qi of jin, mu, shui, huo, tu moving together upward to the heaven and causing abnormal astrological phenomena as groundless; for instance, comets as atmospheric phenomena happened in the sublunar region (Xiong ).

In the past, scholars have proposed many answers to the question, “Why did the scientific revolution not happen in China?” However, it seems to me that no one has approached this question from the viewpoint of natural philosophy, let alone from a comparative viewpoint of history of science. In The Structure of Scientific Revolutions, Thomas Kuhn describes Aristotelian natural philosophy as a pre‐paradigm in the Middle Ages and Renaissance. However, there were several anomalies, such as the 1572 nova, the 1577 comet, Galileo's five discoveries in 1609–1610, and sunspots, which challenged the credibility of Aristotelian natural philosophy and opened a great space for a new paradigm.

Since the 1970s, Chinese scholars began to be familiar with the ideas of paradigm, anomaly, and scientific revolution elucidated by Kuhn. Indeed, some scholars have tried to borrow the term “paradigm” from Kuhn and wondered if “Theory of Ying Yang, Five Phases, and Qi” might be the “paradigm” of Chinese science. The adoption of yin qi and yang qi not only excludes coherence and consistency as criteria for scientific explanation, but also hardly permits any anomaly for the Yin‐Yang Wuxing Qi Lun.

As I mentioned before, there is a Chinese natural philosophy of qi, which has been modified, adjusted, and enriched through different times or ages, but it has never been revolutionized. From our comparative analysis of two sciences, I offer the following list to show my comparison of natural philosophy of qi with Aristotle's natural philosophy.

The competition of two sciences

Matteo Ricci made efforts to replace the five phases (wuxing 五行) with the Aristotelian four elements in his On Four Elements (Si Yuan Xing Lun 四元行論). So far as I know, much earlier Shao Yung (邵雍, 1011–1077 CE) had introduced a minority perspective called di zhi si ti 地之四體, that is, shui (water), huo (fire), tu (earth), shi (stone) 水火土石, to challenge the dominant view of the five phases. Although Ricci did not succeed, he knew this commentary and appropriated it to transmit Aristotle's four elements as “bodies” (ti 體) which comes into being earlier than its function and regarded five phases wuxing as “functions” (yong 用) of Aristotle's four elements (Hsu ).

Since the late sixteenth and early seventeenth centuries, although the transmission of Western science to East Asia brought it into encounter, comparison, and competition with Chinese science, there was no decisive victory for Western science until the second half of nineteenth century, when Western technology based on science was demonstrated through the power of military weapons and ships. Thus, it was scientific technology (or technology based upon science) that persuaded Chinese to believe that Western science and technology were superior to traditional Chinese science and technology.

The Hippocratic Oath as a universal benefit for human beings

Because of its basis in Greek natural philosophy, Greek Hippocratic medicine has been regarded as a rational medicine. Scholars widely believe that one of the students of Hippocrates, often called the father of medicine in Western culture, actually wrote the oath. The oath requires the medical doctor to teach his art to students without reward and imposes a duty to cure all kinds of people, regardless of social rank.

The oath has been regarded as the root of medical ethics. Although it has been modified in the past, modern professional doctors use medical technology along with this medical ethic, for the end of making patients feel more comfortable. In my opinion, the Hippocratic Oath is a universal benefit for human beings.

Positive Confucian belief in politics, ethics, and nature

As I mentioned above, in order to limit the absolute power of the emperor Han Dynasty Confucians chose to borrow the view of wu xing xiangli zhi qi 五行相沴之氣 to introduce the potentially negative relations that may exist among politics, ethics, and nature, reflecting on abnormal phenomena to warn the emperor to correct his misbehavior.

But there also exists a positive relation between politics, ethics, and nature. In the Yao Dian 堯典 of the Shangshu 尚書 (The Document), Emperor Yao made efforts to seek harmony between politics, ethics, and nature. Good politics must follow the natural order of the seasons and provide benefits for the people. This is the positive Confucian belief in the intimate relation between politics, ethics, and nature.

In light of the crisis of air pollution or of global climate change, I think we may reinterpret the negative Confucian relation between politics, ethics, and nature, thereby reflecting on abnormal phenomena as a warning about collective misbehavior in our use of modern scientific technologies. If we want get back on the right track, we need to introduce a positive Confucian belief in politics, ethics, and nature, whereby political leaders should seek harmony between politics, ethics, and nature.