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What does the decree on Copernicanism say?


On March 5, 1616, the Sacred Congregation of the Index, created by Pio V in 1571 for the purpose of examining publications suspected of doctrinal or moral errors and possibly including them in the Index of Prohibited Books, published a new Decree that condemned De revolutionibus orbium caelestium by Nicolaus Copernicus and two other works: In Iob Commentaria by Diego di Zúñiga and the Letter of P.A. Foscarini (…) on the mobility of the earth and the stability of the sun.  The Decree also included a general prohibition of Copernican books (omnes libros idem docentes).

The condemnation of Copernicanism was the first critical episode in the Galilean affair, and it formed an essential prerequisite for his condemnation seventeen years later. Within the sequence of events in which the Pisan scientist was opposed by the Roman authorities, the Decree of 1616 was the only public doctrinal document. However, the question “on the mobility of the earth and the stability of the sun,” as it was then put, had not been properly examined by the Congregation of the Index, which issued the Decree, but rather by the Holy Office, which according to a practice not uncommon directed the Index to impose a sentence already decided. 

The peculiarities of the Decree

This was not the Decree’s only peculiarity. Even if the condemnation of Copernicanism was the reason behind it, it appeared to be secondary. After a long introduction aimed at clarifying the meaning and the extent of the condemnations, the Decree begins by presenting a list of five works by Protestant authors. The suprising fact is that, with one exception, these works were already condemned in previous decrees. The condemnation of Copernicanism appears only afterwards, clearly distinguished from the preceding works from a typographic point of view. Moreover, it takes the form of a long paragraph about the reasons behind the condemnation, unlike the usually short list of condemned books.

What are the reasons for these peculiarities? They concern the process that gave rise to the condemnation.

The decision to condemn the Copernican books did not come from the Index, but rather from the Holy Office, at the end of a long process that began the year before, when the first charges against Galileo arrived in Rome from the Florentine circles. When, at the end of this process, Pope Paul V determined that the Congregation of the Index would attend to the condemnation of Copernican books, he also established that other works should be added, already condemned or to be condemned, chosen from among those considered most dangerous. Paolo Sfrondati, Cardinal of St. Cecilia, was responsible for choosing them; the list seems therefore short of accidental. Four of the five works included had already been condemned the previous year; only one, attributed to Friedrich Achilles, Duke of Württemberg (in reality, a collection of political commentary, edited by Thomas Lancius), was condemned for the first time.

Behind this unusual choice seems to be the desire not to give too much importance to the censorship of the Copernican system, “masking it”, so to speak, behind the censorship of other Protestant works, whose condemnation could thus be seen as a normal occurrence. However, this hypothesis contrasts with the urgency with which everything proceeded in the final weeks of February 1616. Although the issue had been prolonged for more than a year, it was suddenly accelerated in late February. In fifteen days it passed through the consideration of consultors, the examination by the Holy Office and then by the Index to the publication of the Decree. It was not perceived, therefore, as a matter of little importance, but nevertheless, it was not desirable to show that too explicitly. One could assume a certain awareness on the part of the drafters that the issue was not entirely founded from the doctrinal point of view. In fact, the Holy Office did not accept the view expressed by theologians and preferred not to give a ruling publicly. The publication of a Decree that included other works, openly contrary to the Catholic faith, served therefore to “transfer” their “doctrinal gravity” somehow also to Copernican books. In this way it was possible to better prevent any adverse reactions from Galileo’s defenders.

The development of the Decree: the “Galileo affair”

The Decree of the Index against Copernican books was placed, as we have said, at the center of the Galileo affair. The publication of De Revolutionibus Orbium Caelestium by Nicolaus Copernicus in 1543 did not cause particular reactions by the Catholic authorities, with the exception of the attempt by Bartholomew de Spina, Master of the Sacred Palace, to examine the work of Copernicus in order to condemn it, according the testimony of Giovanni Maria Tolosani. Afterwards, there were no other adverse reactions to Copernicus’ doctrine in Roman circles. On the contrary, Copernican astronomy played a role in the reform of the calendar ordered by Gregory XIII in 1582, and directed by Christopher Clavius, a professor of mathematics at the Roman College.

The appearance of Galileo in the astronomical debate in 1610, as a result of the use of the telescope and its astronomical discoveries, transformed the Copernican issue into a current matter, but it also gave rise to the first accusations. On February 7, 1615, the Domenican monk Niccolò Lorini wrote to Cardinal Sfrondati to denounce Galileo’s letter to Benedetto Castelli, in which Galileo explained his view of the compatibility between science and Holy Scripture. A few weeks later, Tommaso Caccini, also a Domenican, spontaneously presented his testimony against Galileo in front of the Holy Office. The matter progressed slowly. The attempts to obtain the original of the letter to Castelli were unsuccessful, and furthermore a doctrinal examination of the copy presented by Lorini had no effect, because the letter, as a whole, was judged consistent with Catholic doctrine. Even the allegations of Caccini, which had hinted at heterodox discourses between “Galileians”, faded away when in late November it was finally possible to question the witnesses. Galileo, meanwhile, decided to move to Rome in December 1615 to try to prevent attacks on Copernicanism, of which he was aware from the beginning.

The Holy Office decided in any case to examine the Letters on the Sunspots published by Galileo in 1612. There is no information on the outcome of this examination, but maybe as a consequence, it was decided in February 1616 to examine the Copernican issue in the form of two theses: the mobility of the earth and the stability of the sun. Although this was an extremely reductive version of Copernican astronomy, Galileo himself had presented these two propositions as “the most principal point of all his doctrine.”

This brings us to the facts that led to the publication of the Decree of 1616. The two issues regarding the mobility of the earth and the stability of the sun were submitted to the qualifiers of the Holy Office on Friday, February 19th. Their answer was already ready Wednesday, February 24th, and the following day the meeting of the Holy Office took place. The judgment given by the qualifiers was extremely rigorous. Both propositions were considered “absurd and false in philosophy”; the immobility of the sun was deemed formally heretical, and the mobility of the earth “at least erroneous in faith”. However, the Congregation of the Holy Office, presided over by Pope Paul V, did not formally validate this judgment, which would have required a public act, which never actually took place. According to the wording of the minutes, there seem to be two decisions made directly by the Pope (which, however, does not exclude that they could have been made with the authority of the Congregation). The first was clearly recorded in the minutes: the order to admonish Galileo to abandon this doctrine. In fact the next day, Friday, February 26th, Galileo was summoned by Cardinal Bellarmine, and he was ordered to abandon this opinion. Being a personal injunction, it did not have relevance from the disciplinary or doctrinal point of view for the majority of Christians, but exclusively for Galileo.

The second decision does not appear on the record, but it is conceivable that it may already have been made at that time: the order to the Congregation of the Index to proceed with the condemnation of the principle books supporting the compatibility of Copernican opinion with Holy Scripture. On Tuesday, March 1st, Cardinal Bellarmine, in whose palace the meeting was held, proposed to the Congregation of the Index, on behalf of the Holy Father, to deliberate on the prohibition of the books by Foscarini, Copernicus and Zúñiga. After a thorough discussion, the cardinals present determined to suspend donec corrigantur (until they were corrected) De Revolutionibus by Copernicus and Commentary on Job by Zúñiga, and to absolutely prohibit Foscarini’s Letter. It was decided to prohibit in the same manner omnes libros idem docentes, or all books in the future that would have supported the same doctrine. On Thursday, March 3rd, in the meeting of the Holy Office, the Pope approved the content of the Decree and ordered its publication, which occurred on Saturday, March 5th, four-hundred years ago.

The Decree’s Value

What doctrinal weight did the Decree of the Congregation of the Index carry? The Holy Office avoided public statements on the doctrinal position of Copernicanism (of the mobility of the earth and the stability of the sun). And although the final resolution of the case was transferred to the Congregation of the Index, in the form of the condemnation or suspension of a few writings, the doctrinal decision in fact was not transferred, because it was the competence of the Holy Office alone. The Congregation of the Index did not possess the competences on  doctrine itself but only the mission to ban or correct harmful books, relying on existing doctrine. The Decree could not therefore presume to define Copernicanism doctrinally. Instead, it was confined to using an already defined position, which would reflect the reason of the conflict. In this way Copernicanism is not defined doctrinally, but only presented in a generic way as a “false Pythagorean doctrine, altogether contrary to the Holy Scripture.” The reference to Pythagoras was already present in the title of Foscarini’s work, while the status of “false” referred to the philosophical or natural point of view. From the theological point of view, the Decree defines Copernicanism as contrary to the Holy Scripture. But this expression was not a “doctrinal definition,” rather the indication of what had given rise to the issue: the contradiction between the mobility of the earth and the immobility of the sun, as advocated by Copernicus, and the assertions of the Holy Scriptures according to the interpretation of the time. The so-called “condemnation of Copernicanism” consisted only in the suspension or prohibition of Copernican texts “in order that this opinion may not creep any further to the prejudice of Catholic truth.”

The Decree of March 5th, 1616, constituted, above all, an error of judgment on the part of the ecclesiastical authorities. It was corrected only in 1757, when Benedict XIV gave the order to remove the general prohibition against Copernican books from the Index of Prohibited Books, even if the individual works condemned remained there until 1822.

At the root of this error, it is possible to see three different erroneous stances on the part of the ecclesiastical authority.

The first one, of philosophical nature, led them to acknowledge the judgment of the “science” then accepted, that judged the Copernican system as false. This acknowledgement, insufficiently examined, was the first and fundamental error by the theological qualifiers and the authorities of the Roman Curia: in front of an intellectual novelty, widespread for some time and staunchly defended by Galileo and others, the sufficient epistemological openness was missing to recognize that a new type of scientific investigation about reality was already underway.

The second stance is precisely theological and concerns the characterization of Copernican theories as “contrary to Scripture.” Even admitting they described a factual situation, a theological examination of Augustinian exegesis, repeatedly cited by Galileo in the Letter to Christina of Lorraine, and of Thomist exegesis, was to be considered; in such exegesis the literal meaning of Scripture does not identify at all with what Galileo called “the pure meaning of the words.” Such an examination, which, from the point of view of Revelation, would have shown the irrelevance of a question concerning the physical order, such as the structure of the universe, was unfortunately totally absent in the process on Copernicanism in 1616 and also later in Galileo’s trial in 1633.

On these insufficient philosophical and theological grounds, the Congregation of the Index’s decision to prohibit or suspend Copernican books in order to prevent a doctrine, not formally condemned but considered dangerous, from harming the faith of the Christian people, appears clearly as a third error, although formulated only on a precautionary way.

The Decree condemning Copernicanism opened a crisis between science and faith, which was difficult to heal over time. Although the Decree, in the proper sense, had no doctrinal or dogmatic significance, it was interpreted by many in this way. The condemnation of Galileo in 1633 aggravated the problem further. Paradoxically, Galileo had grasped the extent of the Decree. The day after its publication, he wrote to Curzio Picchena, the first secretary of Grand Duke Cosimo II, affirming that the Holy Church “did not resolve anything more than that these opinions did not agree with Holy Scripture.” Galileo was aware that the measure did not have a doctrinal character and could have been revoked, and for this reason he tried to reopen the matter after the election of Urban VIII, through his Dialogue Concerning Two Chief World Systems, published in 1632.

Translated from the Italian by Ruth Reinsdorf Tamma