1. Introduction

In the history of interchange between civilisations there seems no parallel to the arrival in China in the 17^th century of a group of Europeans so inspired by religious fervour as were the Jesuits, and, at the same time, so expert in most of those sciences which had developed with the Renaissance and the rise of capitalism1.

China has made considerable progress in the field of science and technology since the 1^st century bc, by inventing paper, and in the 1^st century ad, by developing the world’s first water-powered armillary sphere, detecting for the first time in the world a supernova on 185 ad, and creating the seismometer. Among all Chinese inventions, it is commonly accepted that three of them would change the world: together with paper, woodblock prints (8^th century) would transform the face of literature; gunpowder (9^th century) of war; and the magnetic compass (12^th century) of navigation.

But although China has made significant scientific and technological advances very early, it is said that it has not experienced a knowledge revolution, similar to what Europe experienced after the publication of De revolutionibus orbium coelestium (“On the Revolutions of the Heavenly Spheres”), in 1543, by Nicolaus Copernicus (Ge-Bai-Ni in Chinese, 1473-1543), presenting an alternative model of the universe to the geocentric system of Ptolemy (c. 100-c. 170 ad)2.

First and foremost, in what concerns astronomy and cosmology, one must consider that the period of the Warring States (475-221 bc) and that of the Han Dynasty (206 bc-220 ad) were characterized by speculation in both fields3. Second, we must bear in mind the fact that China remained an imperial feudal society until late (around the beginning of the 20^th century) and this system retained control of its political structures, as well as Confucian principles, determining the difficulty of bringing about transformational change.

This situation caused China to lose ground to Europe in the path of the development of science and technology. It is generally considered that this state of affairs would only suffer significant changes in the 16^th century, with the arrival of the Jesuits in Chinese territory and their effort of transmission of mathematical and astronomical knowledge4, and this deserves a detailed analysis, in our opinion. The Jesuits saw astronomy and mathematics as a privileged way to introduce Christianity in China, due to their specific official characteristic in this country that resulted from the importance of the Calendar, which was proclaimed by the Emperor every year and used by the entire Empire and vassal states as an instrument of weather forecast and future foretelling.

The question of why China did not develop a science to theorize and structure the knowledge that led to its technological inventions, like Europe did, has been analysed by several scholars, namely on what concerns Chinese early opposition to the knowledge the Jesuits attempted to transmit in the 16^th century. Four centuries later, in the first half of the 20^th century, Joseph Needham, a biochemist from the UK addressed this matter and ended up reformulating this question as to “Why did China never experience a scientific revolution as Europe”. His studies led to a monumental work series named “Science and Civilisation in China”5. As Needham puts it:

Astronomy seems to have shared in the general decline of science during the Ming dynasty. Apart from the work of Wang Wei (…) there was that of Wang Kho-Ta somewhat later, e.g. his Hsiang Wei Hsin Phien (“New Account of the Web of Stars”). After the coming of the Jesuits, astronomy re-awakened, and there was a burst of publications6.

Despite this, it is clear the three Chinese inventions mentioned previously have facilitated the transformation of Europe and the transition from the Middle Ages to the Modern Age. Shortly after, Europeans would travel to Asia and transfer Western science to China through the Jesuits. To understand this phenomenon, one must remember that, in 1498, Vasco da Gama arrived in India, paving the way for the Portuguese to reach China in 1513 (Guangzhou). The Portuguese expansion was, since its early start, surrounded by the idea of absorption of infidels into Christianity, which explains the papal bulls that gave the Portuguese power over non-Christian peoples, even before Portuguese travels reached Asia7.

In 1452, Pope Nicholas V would write the Bull Dum Diversas, and in 1455 the Romanus Pontifex, by which he would authorize the construction of churches by the Portuguese in their new territories, and any others conquered in the future, allowing Portugal to also appoint missionaries for them. These decisions would be later confirmed by Pope Callistus III, in 1456, with the Bull Inter Caetera, giving the Order of Christ spiritual jurisdiction to these lands8. The Order of Christ was a military religious group founded by King Denis of Portugal, in 1319, to replace the then recently suppressed military Order of the Templars9.

Altogether, these bulls led to the creation of the Portuguese Padroado (Patronage) of the Orient10. This set of ecclesiastic documents would later culminate in the Papal Bull Praecelsae Devotionis in 151411. The missions of evangelization have been integrated into the work of the Portuguese Padroado of the East, which can be described as “a combination of rights, privileges and duties granted by the pope to the Portuguese king as head of the Roman Catholic Church in wide areas of Asia and Brazil”12.

In the 16^th century, the Padroado’s jurisdiction covered the Catholic churches in the East and all the ecclesiastics and missionaries displaced in Asia were thus subordinated to the King of Portugal, which meant that the influence and power of Portugal (both religious and commercially) took place namely in China and Japan. The spectacular development of the Portuguese missionary presence in Asia commenced with the arrival of the Jesuits, who would reveal to be the most powerful representatives and defendants of the Padroado over the next two centuries.

In Europe, a simultaneous process occurred that would determine the flow of events in the Orient. Indeed, in 1543, the scientific revolution began with the first publication of works by Nicolaus Copernicus13, and Andreas Vesalius (1514-1564)14.

The scientific revolution would consequently be a process of dramatic change in people’s beliefs and thoughts, and also of social structures and knowledge systems, that affected all knowledge dimensions, from mathematics and astronomy, to biology and physics. Scholars and thinkers were concerned for the first time to find the truth without interference of God. A verifiable truth that formulated the laws of nature unchanged by social circumstances15. On the other hand, the scientific revolution in Europe also meant the construction of a “new intellectual community”16, that managed to survive outside the Church and its old structures, something never seen before in Europe.

Nevertheless, it was still the Church that influenced change in Chinese knowledge of astronomy and this happened through the presence of Jesuits in China. For nearly two centuries, Jesuits worked as astronomers in China and even worked as directors of the Beijing Astronomical Observatory. This Observatory was built in 1442, during the Ming Dynasty (1368-1644), and it is one of the oldest observatories in the world17.

This paper aims to analyse this reality from the point of view of the transmission of knowledge by Jesuit astronomers in Beijing in the 17^th century, articulating it with the development of the concept of a planetary system and with simultaneous events unfolded in Europe within the study of the subject of Astronomy.

To understand the occasional resistance of the Chinese astronomers to the Jesuit input to the conceptualization of the planetary system, it is important to revisit the initial conceptual structures. They were erected by Chinese astronomers, as early as the 3^rd century bc, and they would linger as a widely accepted view of the sky in Chinese astronomical corpus of knowledge until the time the Jesuits arrive in China, in the second half of the 16^th century.

2. A Brief Overview of Astronomy in China from a Historical Perspective

Although the study of astronomy in China seems to date back to the 4^th century bc, the first conceptions of a solar system come later with representations shaped by three main schools: the Pei Chou, also called Kai Thien, which means “celestial cover”; the Hun Thien, i.e. the “celestial sphere”; and the Hsüan Yeh, translated as “brightness and darkness”.

While these early Chinese studies of Cosmology already carried with them important notions of space and time, they occasionally still brought along traditional epochal ingenuousness attached to mythological elements, as we will now see18.

2. 1. The Kai Thien (蓋天), or Chou Pei (周髀): “a hemispherical dome”

It is considered as the most archaic of the three schools and its origin would have been posterior to the 3^rd century bc. It represented the heavens as a hemisphere covering the earth – “the heavenly cover” (Kai Thien) – and the earth as an overturned bowl, producing two concentric domes. It is also known as “Chou Pei”, which is the name of the oldest mathematical astronomical work19, which was also the most important text of the Kai Thien School, and it means “the gnomon and the circular paths of the sky”20.

It is believed that the first reference to this theory can be found in the 3^rd century bc extensive body of work Lü Shih Chhun Chhiu (or Lüshi chunqiu 呂氏春秋) translated as “Spring and Autumn of Master Lü”, sometimes also called Lülan 呂覽, i.e. “Lü’s examinations”. This is a collection of treatises on cosmological matters from the late Warring States period. It is generally assumed that the Lüshi chunqiu is the product of a large group of authors21.

Later on, the School of Kai Thien would be described in the works of Wang Chhung, in the Lun Hêng, in 83 ad; Yao Hsin’s Hsin Thien Lun (“Discourse on the Diurnal Revolution”), from around 250 ad; Yü Sung, in 265 ad, Chhiung Thien Lun (“Discourse of the Vastness of Heaven”); and of Tsu Keng-Chih, in the 5^th century ad, namely in Thien Wen Lu (“Astronomical Résumé”)22.

According to the Kai Thien school, the sky is round like an open umbrella and the earth is square like a chessboard. The heavens turn laterally to the left and the sun and the moon both move to the right. The movements of the sun and the moon are slow, while the sky moves very fast. The stars are however motionless in the sky. The sun can only illuminate a certain area and the people who live outside this area will say that the sun did not rise yet23. The sun was therefore perceived as a circumpolar star with a sort of light beam capable of illuminating one or the other part of the Earth and changing position between the winter and summer seasons.

This theory of the celestial sphere with “double vault” would have originated in Babylon, from where it travelled to the Greeks and the Chinese24. In China, this representation includes three lights that are the sun, the moon and the stars, and they are sometimes concealed and sometimes bright, giving day and night. Both the sun and the moon are attached to the sky, and heaven drags them along as it moves25.

In the 20^th century, Herbert Chatley would draw a model of the Kai Thien cosmology, using the calculations of the mathematical book Chou Pei, sustaining that this cosmological model had just enough veracity in it to make it acceptable in the eyes of contemporary geometers26.

Fig. 1. Reconstruction of the Kai Thien cosmology (after Herbert Chatley)

(Herbert Chatley, “The Heavenly Cover”, The Observatory, Vol. 61, n° 764, Jan. 1938. This image is used with the kind permission of the editors.27)

The theory of Chou Pei had some points in common to those of some of the western thinkers like Vitruvius, one century earlier, as well as Timaeus of Plato, around 360 bc, and a Roman astrologer, Nigidius Figulus, in 44 bc28.

2. 2. The Hun Thien School (渾天): “the Celestial Globe”

Although it is considered that this theory must have been known in China in the 4th century bc, by the time Shih Shen shaped his list of stars29, the oldest full description was penned down by the astronomer Chang Hêng, in the 1^st century ad, in his Ling Hsien (“Spiritual Constitution of the Universe”), where he states:

Formerly the sage-kings, wishing to trace (pu) the ways of heaven (thien lu), and to fix the sublime tracks (ling kuei) (the paths of the heavenly bodies), and to ascertain the origins of things, first set a celestial sphere (hun thi), thus rectifying their instrument and establishing degrees (chêng I li tu), so that the imperial pole was fixed. All turned round the heavenly axis in a reliable way which could be studied30.

As we can see, the Emperor was the model for the categorization and designation of the constellations and the pole corresponded to the Emperor himself31. The West would not use a system with an equatorial polar reference until 1585, with Tycho Brahe (designated Di-gu in China, 1546-1601)32.

This school introduced in the process of formation of a Chinese concept of a solar system the image of spherical movements centered on the earth, with heavenly bodies maintaining a uniform circular rotation. The sky combined the three chhen (i.e. phenomena, presumably the sun, the moon and the stars) and the earth comprised the three hsing (that is to say forms, like earth, water and air). Heaven has nine positions (wei), and earth has nine continents (yü)33.

Chang Hêng also makes reference to the method for calculation of this cosmological model:

The measurements are made with the graduated hun instrument (armillary sphere) (thung erh tu chih tsê shih hun i). For calculations the method of two right-angled triangles is used. The shadow of the gnomon faces the heavens and (explains the) meaning of the spheres celestial and terrestrial (hun ti chih i). A difference of a thousand miles south or north in the gnomon´s position means a difference of one inch in the shadow’s length34.

Phenomena and forms could be observed and measured. The sphere is held together by a bond (wei) and nobody knows what exists beyond it, but a name was found for it and that unknown place was called the “cosmos”35. In the sky, the two symbols (the sun and the moon) dance around the ecliptic, surrounding the polar star located in the North Pole. The South Pole is not visible, so no name has been given to it.

In his writings titled Hun I Chu (“Commentary on the Armillary Sphere”), Chang Hêng describes the model more accurately, calling it an “egg”, saying that the earth is like the yolk and lies in the center and is smaller than heavens, which are supported by vapor (chhi) and have water in their lower part. The sky acts according to a principle of normality and never loses its center. The Hun Thien School gives us a conception of a spherical land, with antipodes, at the same time that it perceives and conceptualizes, for the first time, the infinity of space.

This theory would be followed by other Chinese astronomers in the 3^rd Century ad, like Yang Chhüan, in his work Wu Li Lun (“Discourse on the Principles of Things”), and Wang Fan in Hun Thien Hsiang Shuo (“Discourse on Uranographic Models”), as well as Ko Hung in his Chin Shu36. It seemed to have been generally accepted at the end of the Han Dynasty37, although Wang Chhung himself raised his own doubts as to what concerns the implication of the sun moving through water, even though, as a contemporary author, Ko Hung, would put it: “this was not impossible, for dragons, which are very Yang, can live in water38”.

2. 3. The Teachings of Hsüan Yeh (宣夜): “the Infinite Empty Space”

It is thought that all the books related to this school may have been lost and that there remains only the memory of a disciple of what his masters have told him. His name was Chhi Mêng and it is possible that he was a contemporary of Chang Hêng. He was a librarian who remembered what Hsüan Yeh’s masters taught him. They taught him that the heavens were void and empty of substance. The sun, the moon and the stars floated in empty space, moving or remaining motionless, and they are only condensed vapor. Their speed depends on their individual nature because they are attached to nothing.

These ideas can be found in the “History of the Jin Dynasty” (Jin Shu) of the alchemist Ko Hung (Ge Hong), written in the 4^th century ad. It is he who says that:

The books of the Xuan Ye school were all lost, but Qi Meng, one of the imperial librarians, remembered what its masters before his time had taught concerning it. They said that “the heavens were entirely empty and void of substance. When we look up at them we can see they are immensely high and far away, without any bounds. It is like seeing yellow mountains sideways at a great distance, for then they all appear blue, or when we gaze down into a valley a thousand fathoms deep, it seems somber and black. But the blue of the mountains is not a true color, nor is the dark color of the valley really its own. The sun, moon and company of stars float freely in empty space, moving or standing still, and all of them are nothing but condensed vapor39.

Amongst the scholars who followed this school of thoughts was Yü Shi, who discovered the precession of the equinoxes, in his An Thien Lun (“Discussion of whether the Heavens are at Rest”), although Ko Hung and the 7^th century astronomer and mathematician Li Shun-Fêng (currently known as Li Chunfeng) are the most important sources of its views. Despite the absence of theoretical conceptions, this school has permeated Chinese thought to a great extent. Its thoughts would resonate throughout the ages, regardless of the lack of theory resulting from the absence of deductive geometry.

In this representation, the stars were not attached to the Kai Thien hemisphere nor to the Hun Thien spheres. On the other hand, the Kai Thien system would last as a generally accepted model until the 6^th century ad and it was officially adopted at some point in the history of astronomy of China. However, in the 5^th and 6^th centuries, efforts were made to reconcile the Kai Thien and the Hun Thien, insisting that only half of the model was true.

From this moment on, it is generally accepted in China that the Hun Thien sphere is the only correct vision, until the time when the neo-Confucian philosophers, like Chang Tsai (Zhang Zai, 1020-1077), mentioned the emptiness of the heavens, as a result of the Hsüan Yeh tradition: the earth composed of pure Yin, solidly condensed in the center of the universe; the heavens turning left on the periphery; and the fixed stars carried endlessly.

This means that Chinese astronomers were still distant from the restrictive orthodoxy of Hellenistic and medieval Europe and the assumption that celestial bodies were attached to a series of concentric spheres with the earth as the center40. On the other hand, the pole continued to be a fundamental base of Chinese astronomy. In fact, the celestial pole corresponded to the position of the emperor on earth, around which naturally turned the vast system of the Chinese bureaucratic agrarian state.

These concepts preserved their validity until the moment of fusion with modern science after the arrival of the Jesuits. Hsüan Yeh’s thought would persist until the time of the coming of Matteo Ricci (known as Li Madou in China, 1552-1610) arriving in Macao, in 1582, and in Beijing, in 1601, but “there would be a close resemblance between Hsüan Yeh and the system introduced by (post-Jesuit) Europeans41”.

3. The Influence of the Jesuits

China had a period of great development in Astronomy with the first detailed records of astronomical observations beginning as early as the 4^th century bc42, and it observed and recorded celestial phenomena, such as solar and lunar eclipses43, novae and supernova, comets and sunspots44. Then, during the Former Han Dynasty, between 206 and 9 ad, important developments were made in the structuring and conceptualization of our solar system, as described above, and the Board of Astronomy was created as an official department of the Chinese Imperial Government.

The Chinese Board of Astronomers depended on the Tribunal of Rites (Le-Poo or Ly-poo) and it was formed by three sections, the most important being the one in charge of the Calendar, and the others consisting on the department responsible for the auspicious days for performance of the rites and the one setting the prediction of the weather, as well as natural phenomena like earthquakes45. The relevance of this structure in China resulted from the fact that: “According to the Chinese political theory, the emperor ruled the Middle Kingdom46 at the pleasure of Heaven, so events in the heavens signified approval or disfavor of an imperial regime”47.

Let us pause our course of thought briefly on the notion of the “rites” in China. The Chinese society was based on a family system that honored ancestors and that kept ritual sacrifices at the center of it, while it maintained celebrations to the cult of State Confucianism, involving the use of candles and incense. The importance of these rituals was such that it assured status and power to the emperor and governors of China48. For this reason: “Emperors […] became heavily invested in ensuring that the important political and social rituals in a given year take place at favorable points on the astronomical calendar”49.

When the Jesuits arrived in China, the Ming Dynasty (1368-1644) ruled the country and the sciences in general had suffered a considerable decline. They would find, particularly, astronomy and mathematics in a bad condition, almost oblivious of the brilliant discoveries of the past. As such, the Jesuits were able to demonstrate the superiority of Western astronomy, which would lead them to undertake the reform of the Calendar, and then enter the Board of Astronomers.

The Jesuit missions in China of the 16^th and 17^th centuries introduced Western science and astronomy in China, also at the moment when it was in a state of profound transformation in Europe. They made efforts to translate Western works into Chinese; they made countless astronomical observations and succeeded to finish the first modern cartographic work in China; they also learned to appreciate the scientific achievements of Chinese ancient culture and to make them known in Europe. Through their correspondence, European experts discovered Chinese science and culture for the first time.

The Jesuits first entered China through the Portuguese colony in Macao, where they settled and founded St. Paul’s College. The first two Jesuits who entered mainland China were Italians, Michele Ruggieri (1543-1607)50 and Matteo Ricci, who learned the Chinese language and became familiar with Chinese poetry and philosophy. They presented themselves as being willing to share the scientific achievements of the West, especially regarding Mathematics and Astronomy.

3. 1. The Jesuits and the reform of the Calendar

After entering mainland China, in 1588, Ruggieri would return to Rome to ask the Pope to send an embassy to Emperor Wanli51 (1563-1620) to allow Jesuits to reach Beijing, but he would never return to China after that. Italian Jesuit Matteo Ricci arrived in Beijing in 1601, together with Spanish Jesuit Diego de Pantoja (1571-1618), after having been invited by Wang Tso, an officer of the Nanjing Tribunal of Rites, to work on the reform of the Calendar. He would then offer his skills to work with astronomy, geography and mathematics to Emperor Wanli. In China, Ricci counted with the help of Xu Guanqi (Hsü Kuang ch’i, 1562-1633), a scholar converted to Christianity, who collaborated with him in the Chinese translation of the first six books of Euclid52, and Li Zhizao (Li Chih Tsao, 1565-1630), also converted to Christianity.

Realizing the significance of Astronomy for the Chinese Emperor, Ricci would write to Rome asking for missionaries with knowledge in this subject to be sent to Beijing. Consequently, in 1607, an Italian Jesuit, Sabatino de Ursis (1575-1620), would arrive in Beijing to help Ricci in his astronomical work. Most of their teachings, at this time, still involved mainly Greek and Muslim Astronomy, using above all the Ptolemaic System. It was this view of the universe that Ricci would pass to his students in China.

However, a simultaneous process was taking place in Europe, with the so-called “Galileo Affair”53 which began around 1610, when Galileo (Jia-li-lüe in Chinese, 1564-1642) published his Sidereus Nuncius (Starry Messenger) describing the observations he had made with the new telescope, namely the surface of the Moon, the stars never seen before with the naked eye, and the Medicean Stars (later known as the Galilean moons) that appeared to be circling Jupiter (i.e. the four largest moons of Jupiter: Io, Europa, Ganymede, and Callisto). With these observations, he promoted the heliocentric theory of Nicolaus Copernicus and ended up being trialled and condemned, in 1633, by the Church. After the Galileo affair, the Roman Catholic Jesuit order decided to follow geocentrism and ignore the Heliocentric teachings of Copernicus and his followers, even though they were becoming the generally accepted model in European astronomy.

The year of the Galileo affair was also the year that Matteo Ricci passed away. Following Ricci’s death, in 1610, his work was followed by the Portuguese Jesuit Manuel Dias (known in China as Yang Ma-Nuo, 1574-1659), who in 1615 published a Chinese compendium of the Ptolemaic system (Tianwenlüe 天問略). Although he doesn’t advocate the heliocentric system in this book, Dias describes Galileo’s discoveries for the first time in China and the use of the telescope.

Based on a successful prediction of an eclipse by Sabatino de Ursis, Xu Guanqi, then a member of the Tribunal of Rites, asked the other members to appoint the Jesuits responsible for the reform of the Calendar. Nevertheless, in 1616, Sabatino de Ursis was expelled from Beijing to Macao, after a surge of animosity of the locals towards the Jesuits led to a persecution of Christians at the instigation of Shen Ho (Shěn Hè, 沈隺, vice minister of rites in Nanking, d. 1624), where he died in 162054.

In 1619 three Jesuits arrived in Macao: Johann Schreck (known as Terrentius or Terrenz in Europe and Deng Yu-han in China, 1576-1630); Wenzeslau Kirwitzer (1588-1626); and Johann Adam Schall (named Tang Ruo-wang in Chinese, 1591-1666). Terrenz had been accepted at the Accademia dei Lincei with Galileo55. He would offer a telescope to the Emperor of China, in 1634, and then write to Galileo, inviting him to work in China, without success.

Terrenz would then be appointed to fill the job of the reform of the Calendar and Nicholas Longobardo (1559-1654) would help him in this task. In 1629 the wish of Xu Guanqi materialized in a moment when his position was stronger as a member of the imperial council, and the Jesuits are named responsible for the reform of the Calendar. In this year, a Calendrical Bureau (Liju) is established for the introduction of contemporary Western calendrical knowledge, using tools from mathematics and mechanical sciences56.

Johann Adam Schall and Giacomo Rho (1593-1636) will succeed Terrenz after his death in 1630. It is important to note that Schall had probably had the opportunity to meet Galileo and that he had been active in the field of astronomy, precisely determining the difference in longitude between Rome and Beijing. Giacomo Rho would play also an important role in the transmission of European knowledge, in parallel with the reform of the Calendar.

Although the Jesuits initially shared an Earth-centered and largely pre-Copernican astronomy vision with their Chinese hosts (i.e. the Ptolemaic-Aristotelian views of the Hellenistic period)57, Jesuits like Giacomo Rho would present later the model of Tycho Brahe as a standard cosmological model. The Chinese were often fundamentally opposed to it because, as we have seen, they had long believed (according to the ancient doctrine of Hsüan Yeh) that celestial bodies floated in the emptiness of an infinite space. It is important to point out that although this contradicts the Aristotelian view of solid concentric crystalline spheres, where there was no void, but a mass of air between the celestial bodies. Nevertheless, the subject of the void would be debated in Europe, and amongst the Jesuits in the 17th century. The Jesuits would put forward a complex set of arguments, according to which they did not follow thoroughly late medieval theologians and the idea of a vacuum infinite space created by God beyond the world, and whereas instead they recognized the existence of an infinite space beyond heaven58.

There were other Jesuits in favor of Copernican theory, such as Jan Mikołaj Smogulecki (1610-1656) and Venceslaus Pantaleon Kirwitzer (1588-1626). However, Copernican views were still not widespread or fully accepted in China at that time. Eventually, the views of Copernicus, Galileo and Tycho Brahe would triumph in European science, and these ideas slowly permeated in China despite Jesuit efforts to curb them after the “Galileo Affair”. In 1627, Polish Jesuit Michael Boym (1612-1659) enthusiastically presented Johannes Kepler’s59 (1571-1630) tables in Beijing’s Ming court. In the Chinese Handbook of Astronomy, written in Chinese by Adam Schall von Bell, in 1640, the names of Copernicus, Galileo and Tycho Brahe were officially introduced in China.

Schall finally completed the reform of the calendar in 1638. He would then be appointed director of the Observatory in 1645 by the new Manchu emperor Shun Chih (1638-1661)60, who launched the Qing Dynasty in 1636 and conquered Beijing in 1644.

Fig. 2. Johann A. Schall Astronomer and Mandarin

(Unknown author, public domain61)

Schall’s Calendar for 1645 was also approved and officially proclaimed. Once he became responsible for this task, he would reduce the number of existing Calendars from five to two: the first was aimed for the Imperial administration and listed the events of the Sun, the Moon and the planets, together with astronomical observations; the second contained every day information for the general use of the population, namely the auspicious days and weather forecast62.

The precision of these calendars resulted from the use of European astronomical tables: the “Alfonsine Tables”, from 1252; the “Ephemerides Brandeburgicae”, published in 1609; the “Tabulae Frisicae”, from 1611; the tables included in Astronomia Danica, from 1622, by C.S. Longomontanus (using Tycho Brahe’s system); Tabulae Motuum Coelestium Perpetuae, from 1632, by Phillipus Lanbergius (also by means of the Brahe’s system); and the Tabulae Rudolphinae published by Kepler in 1627, and used by Schall in his calculations as of 164663.

3. 2. The Board of Astronomy and the Observatory

In China, the positions of director of the Astronomical Observatory in Beijing and President of the Board of Astronomy gave the holder the statute of Mandarin that carried significant influence with them. For almost two hundred years, these positions were filled by successive Jesuit missionaries.

Before Schall’s reform, one of the most important of the four departments of the Board of Astronomy (Qintianjian, also called Bureau or Tribunal of Astronomy) was the one in charge of the calendar. After Schall was appointed director of the board, he reorganized its structure, dividing the astronomers into two schools: Chinese and Muslim. He tried to create also a Western school of astronomical thought but eventually abandoned the project64. In 1658, he was designated “Mandarin of first class” by the emperor, making him the most influential Westerner in the history of China65.

Schall would rely on the Italian Jesuit mathematician Ludovico Buglio (1606-1682), the Portuguese Gabriel Magalhães (1610-1677), the Polish Jan Mikołaj Smogulecki and the Austrian missionary Johan Grueber (1623-1680) as collaborators in his astronomical work. He would teach European science to Chinese astronomers, build astronomical instruments, and publish approximately thirty books on astronomy in Chinese, one of which was devoted to the telescope and others to the theory of solar and lunar eclipses, as well as catalogues of stars and a summary of European astronomy, integrating the works of Copernicus, Tycho Brahe, Galileo and Kepler.

Nevertheless, there were some setbacks. In 1649, missionaries Buglio and Magalhães would write to Rome accusing Schall of working with superstitious elements related to the Calendar in China, particularly the prediction of lucky days. Rome responded with the formation of a commission to study the case, which would later proclaim a favorable decision, in 1659, confirming the pope’s approval of the work of Schall in the Observatory and his condition as Mandarin of the Chinese court.

The considerable amount of success achieved by Schall in the Chinese court led to strong hostility from some Chinese astronomers, especially two named Yang kuan hsien and Uming Huen. After the early death of emperor Sun chih and the succession in the throne by a council of regents, Schall was attacked by his enemies who accused him of conspiracy, danger to society and promotion of wrong astronomical knowledge. Schall and his collaborators were imprisoned during the seven months of trial. Schall would be sentenced to death and the others two to exile. Only an earthquake that destroyed part of Beijing would convince the judges of his innocence, because the Chinese believed calamities to be a sign of the government’s wrongdoing. Schall would die in 1666 and his innocence would be proclaimed in 166966.

The work of Schall would be followed by Ferdinand Verbiest. In 1669, he would start to replace the instruments on the platform of the Observatory, all cast in bronze, and these are the same instruments visitors can find there till today.

The Beijing Ancient Observatory consists of a platform and it is equipped with eight astronomical instruments built during the Qing Dynasty (1644-1912): Equatorial armilla (赤道经纬仪); Sextant (纪限仪); Altazimuth (地平经纬仪), Azimuth Theodolite (地平经仪), Ecliptic armilla (黄道经纬仪), Celestial globe (天体仪), Quadrant (象限仪), New armillary (玑衡抚辰仪/清代浑仪)67. These instruments were built according to Chinese technology and using European knowledge transferred to China through the Jesuits, namely Ferdinand Verbiest (1623-1688).

Fig. 3. The Astronomical Observatory of Beijing in the 17^th century

(Unknown author, copy from a drawing by Louis Le Comte, in Nouveaux mémoires sur l’état présent de la Chine, t. I, 169668)

This equipment is described in Ferdinand Verbiest’s book De Theoria, Usu et Fabrica Instrumentorum Astronomicorum et Mechanicorum, from 1673. It may be assumed that the founding of a new Astronomical Observatory with instruments of the tychonian tradition was being planned as early as 1664, but these plans were interrupted by the Yang Guangshang episode and the Jesuit trial between 1665 and 166969.

In 1673, Jesuit astronomers Filippo Grimaldi (1639-1712) and Tomas Pereira (1645-1708) arrived in Beijing, and in 1688 Verbiest died and was buried near the tombs of Ricci and Schall in the Jesuit cemetery. From then on, the Jesuits will continue to occupy the position of Director of the Astronomy Council and will succeed in continuing their work of publishing works in astronomy and building astronomical instruments, although they would participate in the controversy surrounding rites, specifically in requesting permission for the Christians to participate in the ceremonies of respect for the ancestors and for Confucius.

The Jesuits maintained the position of Director of the Board until 1805, with the exception of the period between 1665 and 1668, when Schall and his collaborators were being trialled. This fact was more relevant when we think that the Society of Jesus would be suppressed in 1773 and that the work would have been maintained by four ex-Jesuits until 1805.

Their work would still matter in the years after the suppression of the Society. In 1782, Manuel Dias’ study Tianwenlüe would be included in the Complete Library of the Four Treasures (Siku quanshu 四庫全書), commissioned by Qianlong Emperor (1736-1795), even though the editors decided to erase the preface and its references to Christianity, as well as the text related to the observations of Galileo and the telescope70.

4. Conclusion

The process of transmission of European astronomical knowledge to China was possible due to a series of simultaneous events:

• the European discoveries in Asia initiated by the Portuguese;

• the travels of missionaries and their sense of duty of conversion together with the fact that the Jesuits saw in astronomy a privileged way to introduce Christianity in Asia;

• the scientific revolution in Europe;

• the fact that until then knowledge was concentrated in the Church; the need felt by the Chinese central power to learn European skills in Astronomy in order to correct mistakes in the calendar, aiming to achieve accurate weather previsions and predictions of catastrophes.

Together these fortuitous facts led to a monumental change in both worlds in scientific terms: East and West.

Although relevant, the concept of solar system adopted during this process is not the only significant detail of this course of events: the geometric analysis of planetary movements, the idea of the spherical Earth and its division by meridians and parallels, together with the method to predict eclipses, were some of the central scientific developments introduced by the Jesuits in China in the field of astronomy.

Amongst their publications, on the other hand, were catalogues of stars, observations of planets and satellites of Jupiter. One of them stood out from the others: the Tianwenlüe of Manuel Dias, in 1615, is seen today as more than a translation of astronomical knowledge to Chinese, as it gives us details of Chinese contemporaneous environment and the priorities at the time, namely solar and lunar eclipses. It also “marks a new stage in the Jesuit scientific presence in Asia, a change from the initial presenting Western science to China to writing Western science in China”71.

Therefore, it is generally acknowledged that Jesuits have had a positive effect on the development of science and astronomy especially in China, considering that they arrived at a less positive moment. Even after the prohibition of the heliocentric theory, they still used the works of Copernicus, Kepler and, later, Newton (1643-1727), in mathematics, namely calculating the relative positions of celestial bodies72.

Even so, the Jesuits are sometimes pointed the finger at for having failed to transfer knowledge of the heliocentric system of Copernicus. These ideas were used by the Jesuits in China (alongside with the work of Tycho Brahe and Kepler and the traditional system of Ptolemy) until 1616, when they were banned by the Catholic Church. After 1635, the writings of the Jesuits cease to mention the Copernicus system and they show preference for Brahe. The Aristotelian philosophy of nature would be preserved by the Jesuits in the communication with the locals until conclusive proof of the movement of the Earth was presented73. But the events in Europe and the subsequent restraint of the Copernicus cosmological view were not the only obstacle to the transmission and adoption of modern thoughts by the Chinese who were actually still opposed to them as well. As we have seen, they were strong believers in the ancient doctrine of Hsüan Yeh that stated that celestial bodies floated in a void of infinite space.

It was not until 1750 that the Jesuit R. J. Boscovich (1711-1787) accepted the Copernican system in public. The church will then lift the ban on works defending the heliocentric theory in 1757. In 1764, King Joseph I of Portugal would sign an edict dissolving the Society of Jesus. In 1773, the Society was suppressed by Pope Clement XIV but four ex-Jesuits continued in the position of directors of the Board of Astronomers in Beijing until 1805. In 1814, Pope Pius VII reestablished the Jesuits as an order, and they continue their missionary work to this day.

All in all, the history of astronomy in China shows how important political systems are for scientific development. The Jesuits therefore had the role of educating Chinese astronomers, affecting positively their interest in these sciences, helping them in the prediction of eclipses, teaching the geometry of Euclid, registering the movements of celestial bodies, and using new astronomical instruments, such as the telescope. China, on the other hand, was the Jesuit mission with best results. Despite this effort and the fact that they managed to develop their evangelization actions far from the Portuguese censorship, the Jesuits are sometimes accused of forcing Ptolemaic astronomy on the Chinese, and that would delay the acceptance of the Copernican system, even if it is not completely true, because the Jesuits in China spoke more of Tycho than of Ptolemy.

Generally speaking, the reality is that although astronomical teachings of the Jesuit in China were held back by the Galileo affair, the Jesuits were still able to manoeuvre through obstacles and difficulties to reach the heart of the Empire and convert people to Christianity, transmitting at same time modern astronomical knowledge, even if there was resistance to the acceptance of new concepts of the solar system.

In fact, in the 18^th century, Chinese astronomers would still refuse the astronomy of Copernicus, accusing it of incoherence. It was only at the moment the news of the end of the Church’s suppression of heliocentric theory (1757) arrived in China that a manuscript written by the Jesuit Michel Benoist (1715-1744) and published in 1802 that included an explanation of the structure of the cosmos wherein the Copernican heliocentric model figures as a central issue was published in Beijing. His account on the planetary system and the Chinese reactions thereof would have to be covered some other time and subject to a subsequent analysis.