Science in Christian Perspective



Galileo, Churchman
Raymond J. Seeger
National Science Foundation (ret.) 
Washington, D.C.

From: JASA 33 (September 1981): 166-168.

Galileo in the news! A feature editorial, "Galileo's Ordeal and the Modern Age," appeared in the Washington Star, October 30, 1980. It was based upon a report at the recent Synod of Roman Catholic Bishops on its reopening of the celebrated Galileo case. Pope John Paul 11, in his November 9, 1979, address to the Pontifical Academy of Sciences, had remarked, "I wish that theologians, scholars and historians might examine more deeply the Galileo case." The Second Vatican Council, in turn, had deplored in 1964 the current attitude that "faith and science are mutually opposed;" it regarded the Galileo affair as "something that is not altogether without fault on our part ... . ... miserable and unjust." Later (1965) Pope Paul VI had made a gracious remark about Galileo upon a visit to his tomb in Santa Croce, the Westminster Abbey of Italy. It had been Pope Clement XII, the first Florentine Pope since Galileo's burial (1642) in the adjoining Capella, who had his remains transferred to its present tomb-funds having been left for this purpose by Galileo's "last disciple," Vincenzio Viviani, the 18-year old youth who had come to study under the 75-year old master, The church had been reluctant to have any honor bestowed upon a member who had been severely sentenced by Pope Urban VIII. Galileo had been made to abjure publicly in the Dominican convent of Santa Maria Sopra Minerva in Rome his theological errors. His "Dialogue Concerning Two Chief World Systems" (1632) had been prohibited. It was not till 1835 that a new edition of the -Index of Forbidden Books omitted this book, although all specific prohibitions had been removed in 1822 and the general ban on Copernican works abrogated in 1758.

Over the years there have been many interpretations of this dramatic historical event-including current (1955) distortions such as Bertholt Brecht's The Life of Galileo and Georgio de Santillana's The Crime of Galileo (Stillman Drake's studies are highly recommended). Even today the issues are still unresolved, viz., the relation of developing science to dogmatic philosophy, including theology, and the attitude of established institutions to freedom of thought.

It is my personal opinion that Galileo was a loyal churchman. In response to the preliminary reading of his sentence Galileo requested that two specific charges be dropped, namely, that he was not a good Catholic and that, by inference, he had obtained the authorizing Imprimatur by devious or cunning methods. These, accordingly, were omitted. Galileo never attacked the Church per se; he did, however, object to certain Church authorities arrogating to themselves jurisdiction over non-doctrinal science.

Over Galileo's tomb are two figures representing astronomy and geometry-neither symbolic of his greatest contribution to science. At the age of 12 he attended the nearby monastery school of Santa Maria de Vallombrosa, where he actually became a novice. His father anxiously transferred him to the University of Pisa, which he entered as a premedical student at 17 (400 years ago in 1581). Two years later he became fascinated by the geometry being taught by Ostilio Ricci, the tutor to the children of the Grand Duke of Tuscany. At 21, however, Galileo became an academic drop-out owing to lack of funds from his father or from the University, where the argumentative youth was not popular with the professors. Seven years later, without any degree, he returned there as Professor of Mathematics, appointed by the Grand Duke Ferdinando I de' Medici. After a sojourn at the University of Padua he returned twenty years later as Chief Mathematician and Philosopher to the new Grand Duke Cosimo 11.

He himself had insisted upon the title philosopher in view of his interest in natural philosophy (designated Physics by Aristotle). He was neither an Aristotelian nor a Platonist; he did, however, respect Aristotle's reasoning and his belief in a real world. He was not at all a pure mathematician, but rather an applied one. In the spirit of Archimedes he used geometry, particularly its proportionalities, for describing physical phenomena. He regarded mathematics as a tool to gain insight into experiential nature.

Although Galileo occasionally referred to himself as a "Catholic astronomer", he could truly claim this title only in the light of discoveries that he had made by scanning the heavens with telescope (modern opera glass), which he himself had devised and made: mountains on the moon, spots on the sun, crescent phase of Venus, moons about Jupiter. 

The best portrait, I believe, is one he himself used in a parable in The Assayer about "a man endowed with extraordinary curiosity and a very penetrating mind." In the same writing he discussed his own philosophy of science. He had a burning desire to understand physical phenomena (i.e., appearances). "Philosophy," he claimed, "is written in the grand book, the universe ... in the language of mathematics." (N.B. This does not mean the universe is identical with mathematics.) Galileo worked and wrote as a genuine scientist; he recanted as an obedient churchman.

Galileo was truly a mathematical physicist-in modern terms. He rejected the method of his contemporary philosophers, who sought first principles (metaphysical) from which one could hopefully predict phenomena. Galileo, however, started with experimental data and sought physical principles that would describe them. This gap between philosophy and science persists to this day.

In this connection one requires careful observations that can related to precise definitions, preferably in quantitative terms, e.g., the old concept "speed" and a new one "acceleration." Thus mathematics became useful. Galileo was by no means an armchair philosopher; he was interested in practical matters, e.g., a pump that failed to raise water above 27 ft. Galileo worked with his hands; he made his own lenses (better than those of the Dutch discoverer of the telescope, who could not make one adequate for viewing Jupiter's moons until ten years later). Another feature of his investigations was the use of ideal models, e.g., a frictionless plane (again in the spirit of Archimedes).

He was quite sceptical in his approach to nature-well exemplified in his chief work, Two New Sciences (the strength of materials and falling bodies)-a major contribution to the understanding of terrestrial mechanics, a prerequisite to celestial mechanics. Unfortunately, Galileo's work was incomplete so that his false theory of tides was inadequate support for the Copernican theory. He might better have presented the latter as a hypothesis, as advocated by the theologian Robert Cardinal Bellarmine. (i.e., the use of the orbits, including eccentrics and epicycles, as a calculating device "to save the appearances" -in the manner of Ptolemy-qualitatively "better", but not a great improvement quantitatively). Instead, he stubbornly insisted upon it as "the truth." No wonder his publicized pronouncements irritated academic philosophers who then sought refuge in the authority of the Church.

Galileo's first conflict with churchmen, a minor one, grew out of a casual remark made by a professor, Cosimo Boscaglia, to the dowager Grand Duchess Christina of Lorraine at dinner in 1613. He claimed that any motion of the earth would be contrary to the Scriptures. Galileo being absent, his position was defended by his former student and successor at Pisa, the Benedictine monk Benedetto Castelli. Galileo subsequently presented his views succinctly in an informal letter to Castelli. Somehow copies of this letter were circulated so that Galileo felt impelled in 1615 to formalize his views in a letter to the Grand Duchess herself (published 1636). Pope John Paul 11 found it worth referencing: "Galileo formulated important norms of an epistemological character which proved to be indispensable for putting holy scripture and science in agreement." The Pope complimented Galileo for reaffirming the truth of Scripture in his statement that "holy scripture can never lie, on the condition that it be penetrated in its true meaning." It is unfortunate that the Church at that time did not interpret the Scriptures more broadly in the spiritual sense.

In his letter Galileo, quoting St. Augustine and St. Thomas Aquinas, emphasized that "two truths can never contradict each other ... holy scripture and nature alike proceeding from the divine word." (Nowadays we are torn between literalism and liberalism - each representing a view that depends upon one's viewpoint. A reductio ad absurdum is evident in the recent decision of the National Council of Churches to emasculate the Bible, e.g., to replace the wise men with "sages", the boy Jesus with the "child" Jesus, et. al. John Greenleaf Whittier's hymn now reads, "Dear Mother-Father of personkind.") He warned about too literal interpretations as when the Scriptures speak of God's arm or his hand or his eyes-or when we speak of sunrise. Galileo affirmed, "Our opinion is that the scriptures accord perfectly with demonstrated physical truth"-nature being the arbiter for the latter. He quoted Cesare Cardinal Baronius, "The intention of the Holy Ghost is to teach us how one goes to heaven, not how the heaven goes." The Church, however was particularly sensitive to the Protestant promulgation of independent judgment with respect to the Scriptures-a major concern of the Dominican Order of Preachers. (Even now one is confused by the plethora of English translations, each purporting to give the "true" meaning.) Years later (1893) Pope Leo XII in his encyclical Providentissimus Deus presented a relationship between science and religion little different from that of Galileo.

Meanwhile, a Dominican friar, Tommaso Caccini, had preached (1614) a sermon at Santa Maria Novella on Joshua 10:72"Sun, stand thou still . . . and thou, moon," and a Dominican Niccolo Lorini had sent (1615) a copy of the Castelli letter to one of the Inquisitors-General in Rome. Galileo decided to press the matter by arguing it personally there. He was anxious to prevent the Church from prohibiting the Copernican point of view; he did not insist upon the Church adopting it; rather, in the spirit of St. Thomas Aquinas, who distinguished two realms of truth (faith and reason), each independent and limited, he sought freedom for investigating natural phenomena. Whereas Copernicus had been publicly mocked, Galileo incurred open hostility, partly because of his own aggressiveness and partly because his writings were in popular Italian rather than in learned Latin, but, above all, because the tell-tale telescope could be understood by even the illiterate.

Pope Paul V was eager for a decision on the Copernican theory by the Sacred Congregation of the Holy Office (established 1542). Its consultors censured two propositions, viz., that the sun is immovable at the center of the world, and that the earth is movable and not at the center of the world. They judged the new astronomy to contradict the Scriptures-a hasty conclusion in which all participants, including Galileo, were partly to blame. Both opinions were completely out of order inasmuch as neither proposition was a matter of "faith or morality" as stipulated by the Council of Trent (1545-1563) to be considered of theological concern.

Although Galileo had not been directly involved, he was subsequently admonished by Cardinal Bellarmine not to "hold or defend" the Copernican system. He requested and received a certificate from the cardinal to indicate that he himself had not been called by the Holy Office. Unfortunately, the only report of this event (in the Holy Office) was not signed; it has the additional injunction "not to teach." This document became of paramount importance later in Galileo's trial. It is still a matter of controversy, but it is certainly not a forgery-even though probably "illegal." At any rate the procedure was somewhat questionable. It is noteworthy that the objection to Copernicus' theory was not confined to Catholics or even Italians; it was generally condemned by philosophers and theologians. (Martin Luther regarded the theory as the work of a fool; his friend Philip Melanchthan considered it not honest or decent for teaching. Even as late as the early 18th century John Wesley believed it tended to infidelity.)

Galileo maintained silence until the election of his long-time friend Maffeo Cardinal Barberini as Pope Urban VIII, to whom he dedicated his scientific manifesto, The Assayer, in 1623. The following year he visited Rome to secure a papal blessing for his projected work presenting a tidal theory as evidence of the truth of Copernican theory. He was cordially received and encouraged to write his book, provided it stressed the hypothetical nature of the idea (the tides were not to be mentioned in the title). The Pope, however, apparently did not make it quite clear just what Galileo could and could not say, relying upon his own judgment as to what would consitute an impartial mathematical presentation. The final product The Dialogue, could at best, be termed a "roguish compliance; " there is never any doubt as to the author's intent. The coup de grace was his manner of including the requested reservation of the Pope, viz., that an omnipotent God could make the universe a mystery even to rational men. Galileo had the remark inserted incidentally by Simplicio (probably named after a distinguised 6th-century Aristotelian, but actually a simpleton in this role, as contrasted with the other two interlocutors, the urbane Venetian Sagredo and the clever Florentine Salviati (representing Galileo)-an unintentional slight. Urban, a keenly observant person who brooked no contradiction, was persuaded by Galileo's enemies that he had been betrayed in this seeming caricature.

Thus arose Galileo's second conflict, the major one, with Church authorities. He was summarily summoned to report to the Holy Office for questioning. After the first hearing the Dominican friar Firenzuola, Commissary General, apparently persuaded Galileo to confess the error of his ways in the hope of a lenient sentence-a "deal" that did not materialize. The pope's final judgment was given in quite a different vein. On the basis of "a vehement suspicion of heresy," Galileo was required to make public abjuration of his scientific opinions in the Dominican Convent of Maria Sopra Minerva on 22 June 1633 and committed to life imprisonment; his book was prohibited, and he himself forbidden to treat in any manner questions as to the stability of the sun and the mobility of the earth. (There could be no decision as to heresy inasmuch as the Copernican theory had never been judged by an "infallible authority.") His trial bad been the natural climax of machinations by a motley coalition of jealous Jesuits and domineering Dominicans (individuals-not the Society nor the Ordery, of dogmatic theologians and authoritarian philosophers. Galileo himself, to be sure, was not guiltless; he had given evasive answers and had failed to report BellaTmine's admonition. The sentence, however, was not at all commensurate with his misdemeanor; the punishment did not fit the "crime." What is more, Galileo himself must have experienced a keen inner conflict, torn between his loyalty to the Church and his commitment to free inquiry in scientific matters. At the end he had as alternatives, church excommunication or personal perjury. He bowed in obedience to the Church.

Little is know of Galileo's personal religion other than is revealed in his famous letters. He was certainly sincere in his belief in a Supreme Being. He spoke of the Divine Artificer, "the great Architect." In the case of his own telescopic discoveries he acknowledged that he was "illuminated by divine grace." He was not, however, spiritually minded as is seen by the permission granted to have his daughter (Virginia), the nun Maria Celeste, relieve him of his penance, i.e., to say the seven penitential psalms weekly for three years.

It is not for us to judge Galileo ex post facto: what would we have done under the circumstances? We can, however, try to understand him from his viewpoint and regard him sympathetically from our own.

As a person Galileo exhibited sincere humility before the altar of scientific truth. On occasions, he admitted, "I do not know ' " With respect to the nature of comets he insisted, "I wish to discover the truth". His attitude, of course, was quite different from that of modern physicists, who have generally abandoned the quest for abstract truth and are content if a theory-possibly more than one-is true to the observed phenomena. He enjoyed doing things himself.

Galileo was a polemicist, good at debate, quick witted. He was wont to amplify his opponents' arguments, even strengthen them, and then demolish them completely, much to the advocates' chagrin. He would not give up without a struggle; he did not suffer defeat gracefully. He was stubborn; he would not compromise. He made his 1616 trip to Rome despite the advice of friends; he persisted in defending the Copernican system as uniquely true despite equally good evidence for the Tychonic proposal not even mentioned in his Dialogue. There is a myth (due to Guiseppe Baretti 1757) that he muttered, "Eppur si muove" (Yet it does move), when he rose humiliated from his abj uration- hardly likely. Upon his leaving his friendly host at Siena, where he had been first "imprisoned," he might have so remarked slyly as he bade his wellwishers, "arrivederla." Galileo was certainly an optimist; until the judgment, he seemed to expect matters to turn out all right. After all, he had many friends in high places (including the Church).

Galileo was quite imaginative so that he was popular as an expositor and as a lecturer. He wrote in Italian so that the common people could understand his message. He had a flare for the dramatic, It is not unlikely that the old Galileo reminisced with the young Viviani, who later told the tale, that for a group of students he had dropped two different weights simultaneously from the Leaning Tower of Pisa to demonstrate that the difference in times of fall was considerably different from what might have been expected from Aristotle's assumption.

Galileo was unquestionably self-centered. He enjoyed the comfortable hospitality of his friends, their good houses, good food, and good wines. His own house in Arcetri, where he was under house arrest, was a small estate in the country. When he abandoned his Paduan mistress he took their three children with him to Florence, where the two girls (under ten) were at once confined to a nunnery for life. At the very end he indulged himself with his scientific interests. But he was by no means a martyr of science! Priorities continually bothered him-in the case of the telescope, of sunspots, and of comets. At the end of his second hearing he pleaded pitifully that consideration be given to his bodily ailments, his honor, and his reputation.

At best, Galileo was honest only to a degree. Only partially true was his claim in The Assayer, "Poor as I am, I am at least upright." I do believe, however, that he was correct about Bellarmine not instructing him in 1616 with the incriminating phrase "not to teach" Copernican views. When Galileo was questioned about his intention with respect to his sentence, he committed downright perjury, viz., "I affirm, therefore, on my conscience, that I do not now hold the condemned opinion [Copernicusl and have not held it since the decision of the authorities." (1616) Galileo's behavior was in some respects blameworthy and in others praiseworthy. His admittance at the second hearing rings true: "My error has been, and I confess it, one of vainglorious ambition and inadvertence" -typically human.

Undoubtedly he helped free scientific thought-but only at the costly price of its divorce from culture (cf. our modern "two cultures ")-what Brecht calls the real "crime of Galileo." In his play where the people are the hero, not Galileo, he captions the last scene with this reference to the "Two New Sciences":

"The great book o'er the border went 
And, good folks, that was the end. 
But we hope you'll keep in mine 
He and I were left behind."

The Galileo case is usually cited as a dramatic focus on the supposed warfare between science and theology. Actually it is merely an instance of the perpetual clash between an individual's freedom of thought and society's establishment of authority. It just happened then that the person was a scientist and the institution the Church. The issue itself is still alive today, but such conflict is not inevitable. It would not have taken place in the 17th century if Galileo's scientific attitude had been as broad as Bellarmine's, and if the latter's theological point of view had been as broad as Galileo's. Conflicts between the individual and society are always taking place; this particular one occurred in an area where truth was verifiable to a degree. But both Galileo and Bellarmine were wrong in allowing the Bible to be used at all as a science textbook even where there was no apparent objection.

I personally believe that there will always be some kinds of conflict between science and theology inasmuch as each gives an incomplete and continually changing view of the same world from differing viewpoints.

This is the first in a special series on religious scientists.