The Popes and Science

It is sometimes assumed in the modern time, and it used to be the custom a generation ago for nearly everyone in English-speaking countries to assume, that because we knew very little about science in the medieval period it must be because there was very little to know. We have learned the fallacy of that supposition to our cost, by the republication of the great text-books of medicine and surgery of the medieval period and by the deeper study of such great scholars as Roger Bacon, Albertus Magnus and St. Thomas Aquinas. Even the scanty records that we have show us the Popes following the same sort of policy with regard to education and science as at the present time. Men who collected scientific information for academic or popular diffusion, as Isidore of Seville, Albertus Magnus, Thomas of Aquin, were not infrequently raised to ecclesiastical dignities during life and placed among the saints after death. Occasionally a distinguished scientist like Gerbert, who became Pope Sylvester II, or Petrus Hispanus the well-known physician, who became Pope John XXI, were even made Popes. It is easy to understand that their attitude as Supreme Pontiffs towards science would be not only not one of opposition but of sympathy and helpful patronage.

While as I have said astronomy as a formal science practically did not develop until the Renaissance, there were a series of important discussions of the relations of the earth to the other heavenly bodies and of the size and shape of the earth itself among the professors of the medieval universities, and the perfect freedom with which these discussions were carried on shows how unshackled was human thought. Albertus Magnus discussed the antipodes, dismissed the notion that if there were men on the other side of the earth they would surely fall off by the thoroughly Socratic remark that we ourselves were on the other side from them yet did not fall off, and understood and taught very definitely the rotundity of the earth and other doctrines that are usually supposed to be much more recent, and that are often said to have brought their holders into ecclesiastical odium. Far from this, Albert was always in high favor and was made a bishop and canonized as a saint after his death.

Roger Bacon studied light, declared that it moved with a definite velocity and gathered and made good use in his teaching of an immense amount of information in the departments of knowledge that we now call astronomy and geography. Humboldt declared that it was a passage from Roger Bacon which more than anything else, even the Toscanelli letters, roused Columbus to his life purpose of sailing westwards. Roger Bacon's books, the one with the paragraph now famous because of its connection with Columbus among the number, were issued at the request of the Pope and it seems very probable that we would have had no idea of his marvellous anticipation of many modern scientific truths only for the definitely expressed wish of the Pope to know the English Franciscan's thought. We have just celebrated the seventh centenary of Roger Bacon's birth, and this has brought home to us how much of a loss to the history of human culture would have been the missing of Bacon's works. Bacon's difficulties in life were with his Order and were personal matters not directly connected with his science.

With the beginning of the Renaissance the stimulating effect of the study of Greek science on the men of the fifteenth century was exerted and one of those who was most deeply touched by the Greek spirit was Cardinal Nicholas of Cusa, or Cusanus, as he is called from the Latin name of his birthplace. He wrote a series of books touching many matters in science and treating various phases of mathematics. He dwelt particularly on certain problems relating to geography and astronomy. I have summed up his scientific career in a chapter of "Old Time Makers of Medicine" (N. Y., 1911). He taught the rotundity of the earth and that the earth was the same sort of a body as the other stars in the heavens, that it was not and could not be the centre of the universe and that it had a movement of its own. Far from such revolutionary teaching leading to his persecution or bringing him under the suspicion of the ecclesiastical authorities he was, on the contrary, looked up to for his scholarship, received successive ecclesiastical preferments, became Bishop of Brixen and then Papal Legate to Germany for the reform of abuses, and finally a Cardinal. He did much to encourage interest in mathematical, geographical and astronomical science, provided opportunities for students, encouraged Puerbach and Regiomontanus in their significant pioneer work in mathematics and astronomy, and generally showed himself the enlightened patron of every movement related to the physical sciences, and all the workers with the experimental method.

The first epoch-making astronomer who was brought into intimate relations with the Pope of whom we have definite knowledge was Regiomontanus. He is deservedly known as the Father of Modern Astronomy for his initiation of series of calculations and publications with regard to the heavens and his establishment at Nuremburg of a regular observatory. He was summoned to Rome to direct the calculations for the correction of the calendar, but unfortunately died there at the early age of forty. His invitation to Rome for this purpose came within the same decade when, if we were to trust certain modern historians of the relations of the Popes to science, Pope Calixtus III issued his supposed bull against Halley's comet. The bull has never been found. The attitude of the Popes towards science is much better illustrated by the invitation to Regiomontanus and the encouragement of astronomical research thus afforded than by the fictitious bull against the comet. The supposed bull has, however, played a large role in convincing a number of people of Church opposition to science, some of them being professors of science who knew nothing about the almost simultaneous appointment of Regiomontanus as Papal Astronomer.

Toscanelli, over the question of whose influence on Columbus an as yet unsettled controversy is waged, was a lifelong friend of Nicholas of Cusa, they had been schoolmates at College and undoubtedly the great cardinal doctor of laws or of decrees as they said at that time, owed much of his progressive advanced views on scientific subjects to his Florentine friend "the doctor of physic, Paul Toscanelli." Cusanus at the height of his fame dedicated his book on Geometrical Transformations "to Paul the Florentine physician." Regiomontanus, as well as Cusa, often sought Toscanelli's opinion on abstruse questions of mathematics and quoted him with confidence. The intimate relations of Cusanus and Regiomontanus with the Popes of the middle of the fifteenth century are very well known. Toscanelli's services to astronomy are only less famous than those to cosmography. A series of his careful and painstaking observations and calculations of the orbits of the comets of 1433, 1449-50, of Halley's comet of 1456 and of the comets of 1457 and 1472 are preserved in manuscript. They demonstrate his profound and successful interest in astronomical subject and it is easy to see that they must have cost him, as indeed he tells in his letters, many a night's watching of the stars. The relations between the ecclesiastical authorities and Toscanelli are very well illustrated by that well-known monument to his astronomical skill which still interests visitors so much in the Cathedral of Santa Maria del Fiore at Florence. This is the gnomon arranged in the dome of the Cathedral by the shadow of which it is said that he could determine midday to within half a second. The use of the Cathedral for this purpose is interesting testimony to the cordial relations of science and religion at this time. It may be said in passing that Toscanelli's gnomon was later improved by Cardinal Ximenes of Spain, showing that these cordial ecclesiastical relations with science were not confined to Italy.

While Toscanelli was making his observations Antoninus of Florence was for some thirteen years the Archbishop of the city and was one of the learned members of the Dominican Order at this time, who had made his novitiate among the Dominicans with Fra Angelico and Fra Bartholomeo the great Renaissance painters. Antoninus was greatly influenced evidently by his associations with Toscanelli and formed one of a group of men containing the Florentine physician astronomer, Cardinal Cusanus and Regiomontanus, himself afterwards a bishop, who were on terms of intimate relationship at least in scholarly matters at this period. Archbishop Antoninus, who is the author of a Summa Theologica Moralis of which no less than fifteen editions were printed after his death, wrote also a series of histories in which he shows this influence by insisting that comets are celestial bodies like the others in the heavens and had no effect on the physical or moral conditions of the world and, quite contrary to popular beliefs, were not responsible for war or pestilence nor prophetic of evil to mankind. There had been a number of brilliant comets in the heavens about this time and there was consequently a widespread interest in them and much popular superstition with regard to them. Antoninus was on terms of familiar intimacy with Pope Eugene IV, who insisted on his becoming Archbishop of Florence, though Antoninus would have preferred to have remained a simple Dominican and keep his leisure for his scholarly work. When the Pope felt his end approaching he called Antoninus to Rome to administer the last rites of the Church to him and be by his side during his last hours. Antoninus was frequently consulted by Pope Eugene's successors, Nicholas V and Pius II, both of whom were among the scholarly patrons of learning and art at this time. Some fifty years after his death Antoninus was canonized by Pope Hadrian VI, the scholarly Pope from Utrecht in Holland. His whole career then shows clearly the relations of the ecclesiastics and particularly the Popes of the time to science in a most favorable light.

The relationship with the rising science of the Renaissance period thus initiated was continued during the following century. At the end of the fifteenth century Copernicus studied for ten years in Italy and felt so thoroughly the interest of Italians in advances in science as well as scholarship that when some years later he came to formulate his great new hypothesis of the heavens, he sent an abstract of his theory to some of the Roman teachers with whom he had become intimate during his stay and it was taught publicly in the city to crowded audiences. This may well seem surprising to many whose only knowledge of the relations of the Popes to astronomy is the Galileo incident, but it must not be forgotten that Copernicus' great work in which he elaborated his theory, was dedicated, with permission, to the Pope, and not only received no censure until Galileo's time, nearly a century later, but was welcomed as a great contribution to science and thought. It was looked upon as a theory, to be discussed as any other. When Galileo, at the end of the first quarter of the seventeenth century, insisted on teaching it as absolute science, it must not be forgotten that there were no astronomers in Europe who looked upon Copernicanism as an accepted scientific doctrine. Even the reasons advanced by Galileo for its acceptance have all since been rejected. Owing to the discussions of it far and wide in the time of Galileo, certain expressions in Copernicus' great work were required by the Church authorities to be corrected so that his explanation of the heavens should be presented as the theory that it was and not as an absolute doctrine of science.

Toward the end of the sixteenth century the necessity for the correction of the calendar became more urgently manifest and Pope Gregory XIII invited Father Clavius, S.J., to take up the subject. At this time also, as is described by Pope Leo XIII in his Motu Proprio of 1891, "Gregory XIII [nearly half a century before the condemnation of Galileo] ordered a tower to be erected in a convenient part of the Vatican buildings and to be fitted out with the greatest and best instruments of the time. There he held the meetings of the learned men to whom the reform of the calendar had been entrusted. The tower stands to this day a witness to the munificence of its founder. It contains a meridian line by Ignazio Danti of Perugia, with a round marble plate in the centre, adorned with scientific designs. When touched by the rays of the sun that are allowed to enter from above, the designs demonstrate the error of the old reckoning and the correctness of the reform." It was evidently the intention of the Pope that there should be, as a permanent institution in Rome, an astronomical observatory fully equipped and supported by the revenues of the Holy See and with a prominent scientist at its head. This purpose has been constantly kept in mind by the Popes ever since, though not long after Gregory's time, but not at all because of any opposition to science, the observatory founded by him came for more than a century not to be used for the purpose intended because its place was supplied by another Roman institution directly under the patronage of the Popes.

This was the Roman College, the great central school of the Jesuits, in the capital of Christendom. That Order was scarcely fifty years in existence in Pope Gregory XIII's time, yet it was to a member of it that the Pope turned for expert scientific direction in the correction of the calendar. During the next three centuries science as patronized by the Popes in Rome was mainly in the hands of the Jesuits. When it is recalled that this Order is directly under the control of the Pope, the professed members taking a special vow of obedience to him, it will be understood that the Jesuit policy with regard to science must be taken as representing the Papal position in its regard. If it is further recalled that Poggendorff in his Biographical Lexicon of Men Eminent in Science gives the names of some 500 Jesuits, though the Order was not in a position to do any work in science until 1550, it will be readily appreciated that the Popes acted wisely to encourage an institute so prolific in eminent scientists in its scientific work at the Roman College, rather than maintain a separate scientific department at the Vatican. The second institution would only have been unnecessary duplication of staffs and the connection between teaching and research at the Roman College was better for both functions.

Father Christopher Clavius, to whom more than to any other is due the Gregorian reform of the calendar, a magnificent practical application of astronomy and mathematics, is an excellent example of the men who were near the Popes as counsellors and scientific advisers just before Galileo's time. Indeed Galileo and he were on the most friendly terms until his death in 1612. The circle of his friends included such men as Kepler, Tycho-Brahe and other great scientists of his time and he was called "the Euclid of the sixteenth century." His works were published at Mainz, in five huge folio volumes in a collective edition. The third of these is a commentary upon the Sphaera of John Holywood (Joannes de Sacro Bosco, the great medieval mathematician) and a dissertation upon the Astrolabe. The fourth volume contains a very full discussion of Gnomonics, that is, the art of constructing instruments of all kinds for determining the time by means of the sun. The fifth volume contains his papers with regard to the reform of the calendar. Most of these books were issued in many editions before and after his death, and their publication over and over again shows very clearly how much the men of the sixteenth and seventeenth centuries were interested in scientific subjects and how often and quite properly they looked to great clerical teachers as their leaders in science.

Just about the time that the Galileo matter was disturbing scientific and ecclesiastical circles at Rome, Father Scheiner, the Jesuit mathematician and astronomer became Professor of Mathematics in the Roman College. He is the inventor of the pantograph or copying instrument for drawings, and, being of an ingenious inventive disposition, constructed a number of instruments for astronomical investigation. He studied the sun carefully through colored glasses in a helioscope and then conceived the idea of projecting the sun's image on a screen in order to study its surface. Kepler used this same method, but Scheiner is said to have the right of priority in it. In March, 1611, he discovered by this method spots on the sun and while the priority of discovery was disputed by Galileo, three men, Fabricius, Galileo and Scheiner, seem all to have done their work independently in this matter, Fabricius being probably the first in time. For nearly a score of years Father Scheiner continued his observations on the sun and published his great work, which in the fashion of the day was called by the somewhat fantastic title, Rosa Ursina. He had the true scientific spirit and devoted himself to other subjects besides astronomy. He made important researches on the eye, showing that the retina is the seat of vision, and devised the optical experiment which bears his name.

One of Clavius' pupils was Father Matteo Ricci, S.J., founder of the Catholic missions of China, who in the midst of his successful studies of mathematics and astronomy at the Roman College asked, at the age of twenty-five, to be sent on the missions in farthest Asia and was allowed to go the following year. He was selected to found missions in China and succeeded in breaking through the Oriental reserve and contempt for everything Occidental of the Chinese, and thus gained a foothold for Christianity in the country. It was Father Ricci's learning, particularly in cosmology, mathematics, astronomy and geography, that attracted the attention of the Chinese. He introduced astronomical studies at Pekin and brought over a series of instruments for an observatory which were so well thought of that they were preserved until our own time and some of them are said to have been taken from the Chinese capital by the allied troops, after the capture of the city following the Boxer Rebellion. He not only taught the Chinese European science, but he sent back to Europe true accounts of China and, above all, encouraged scientific studies among the missionaries. The example he thus set has always been followed and there has scarcely been a generation since when some Christian missionary has not been making original observations in natural history and collecting curious specimens to be sent home to scientists in Europe, while at the same time faithfully pursuing his missionary work.

Early in the seventeenth century, indeed just at the time when the Galileo case was most prominent at Rome, Father Athanasius Kircher was summoned to Rome and began his scientific work there, which included contributions to every department of physical and even some of the biological sciences. For some five years about the middle of the seventeenth century Father Kircher devoted himself to astronomy and the result was the publication, in 1656, of an astronomical treatise called Iter Celeste. A second volume on astronomy appeared in 1660. Anyone who is inclined to think that these contributions of the great professor of science at the Roman College were only reviews of the passing scientific opinions of the time, is not fully acquainted with Father Kircher's work. He never failed to illuminate anything that he set himself to study. His book on astronomy is of course a text-book, but it is magnificently illustrated; it is a very large work which shows the author's familiarity with the scientific literature of the time, but at the same time reveals his own scientific genius. Father Kircher was encouraged in every way by the Popes and high ecclesiastics of Rome and by his own Order, and his great text-books are among the bibliographic treasures of the history of science. Some idea of his industry may be gathered from the fact that he wrote altogether some forty volumes folio on scientific subjects. He made many original observations, invented a number of valuable scientific instruments that are still in use, among others the vernier and magic lantern, and was productively occupied with nearly every branch of science in his time.

During the eighteenth century, before the suppression of the Jesuits, another distinguished mathematician and astronomer, famous throughout Europe, was working at the Roman College. This was Father Boscovitch, to whom we owe the plans for the erection of an observatory above the great pillars of the Church of the Gesu at Rome, which were not destined to be executed until the middle of the nineteenth century. Boscovitch is famous for a series of important works in mathematics and astronomy. He wrote books on Sun Spots, the Transit of Mercury, the Aurora Borealis, the Figure of the Earth, the Various Effects of Gravity, the Aberration of the Fixed Stars, and other astronomical problems. Pope Benedict XIV commissioned him and his brother Jesuit, Father Le Maire, to carry out several precise meridian arc measurements. He is the inventor of the rock crystal prismatic micrometer, the ring micrometer. After the suppression of the Jesuits Father Boscovitch was made Director of Optics for the Marine, a post created for him in order to secure his services for France.

During the second period of the history of the Vatican Observatory at the end of the eighteenth and the beginning of the nineteenth century, the upper story of the Gregorian tower was fitted up with meteorological and magnetic instruments with a seismograph, a Dolland telescope, a small transit instrument and a pendulum clock and a series of very careful observations on a number of subjects made. From 1800 to 1821 Gilii made an uninterrupted series of meteorological observations, reading the instruments twice a day, at 6 a.m. and 2 p.m. The observations are published for seven years and the rest are preserved as manuscripts in the Vatican Library. There are also deposited astronomical observations of eclipses, comets, Jupiter's satellites and of a transit of Mercury. Gilii laid down the meridian line in front of St. Peter's with the obelisk as a gnomon and the readings of the seasons by the length of the shadow. To him are due also the bronze marks on the floor of St. Peters, giving the comparative lengths of the greatest churches of the world. It was he who placed the first lightning rod on the cupola of St. Peter's. The heavens, the weather, the lightning are supposed often to be set by religiously inclined persons particularly under the care of Providence, to be influenced by prayer, yet these are exactly the three departments of science that were faithfully followed in their detailed scientific aspects during all the centuries by the Papal Astronomers under the patronage and with the approval of the Popes, with the avowed purpose of discovering the natural laws under which they occur.

Two of the distinguished teachers of mathematics and astronomy of the end of the eighteenth century at Rome were Father Thomas Leseur, professor at the Sapienza, and Professor Franz Jacquier, professor at the Roman College, who wrote a commentary on Isaac Newton's Principia which did much to popularize Newton's work.

When, because political influence was brought to bear very strongly on the Pope, the Jesuits were suppressed in 1773, the Roman College passed from their hands and the real reason for allowing the Vatican Observatory on the Papal grounds to fall into disuse was manifest, for the Popes at once took up the question of re-establishing their own observatory. Not long after the suppression we find Monsignor Filippo Luigi Gilii placed in charge of the reorganized Roman Observatory by Cardinal Zelada, who had been appointed Vatican Librarian in 1780, and who found the old Gregorian tower available as a centre of astronomical observation and investigation of which Rome had been deprived since the suppression of the Roman College. After the restoration of the Jesuits early in the nineteenth century, the Roman College was opened once more and distinguished Jesuits, some of them with world-wide reputations, did their work there. With the occupation of Rome by the Italian government in 1870 the Jesuits were banished, the Roman College with its observatory was once more deprived of the learned expert direction of the Fathers of the Order, and once more efforts were made for the re-establishment of a Vatican observatory which is now in existence and under the direction of a Jesuit.