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Galileo Heretic: Book Review

Galileo Heretic by Pietro Redondi

On the morning of February 26 1616 when Galileo stood before the intimidating Jesuit Cardinal, Roberto Bellarmino, he understood immediately the dangerous position he was in. He had been summoned to the Vatican Palace by Bellarmino to be told that a decision had just been taken to condemn Copernicus for his blasphemous heliocentrism (ie that the earth and the planets revolve around the sun).

A year earlier Galileo had defended heliocentrism but had taken care to emphasize that this concept of astronomy was not in fact contrary to the Holy Scripture if one takes the approach of Saint Augustine that when the Bible seems to contradict science and reason it should be interpreted metaphorically rather than literally.

But this was the time of the Counter-Reformation and at its center the Roman Inquisition was in full swing with Bellarmino as Chief Inquisitor, therefore subtle and intelligent arguments were given short thrift. Heretics were to be rooted out and burned and Galileo would have been well aware that one of Bellarmino’s first acts as a Cardinal Inquisitor 16 years previously was to preside at the trial of Giordano Bruno. Bruno was a Dominican friar, philosopher and astronomer who supported and expanded on Copernican theory. He was declared a heretic and hung upside down in the Campo dei Fiori in Rome and burned to death.

Giordano Bruno statue in Campo dei Fiori

There is a statue of Bruno today (above photo) on that very same spot in Rome but as an example of the dogmatic inflexibility and continuing hypocrisy of the Catholic Church, on the 400th anniversary of Bruno’s unpleasant death Cardinal Angelo Sodano defended the prosecution. (It later emerged that this same overly pious Sodano spent many years covering up sexual abuse and pressing people in power in various countries to drop criminal charges against priests, ultimately leading to his resignation as a Cardinal. Bruno’s fate would I think have been a fitting end for Sodano also).

Saint Roberto Bellarmino
Saint Roberto Bellarmino

Galileo lived in a very different time to his illustrious predecessors of the Italian Renaissance. The Catholic Church in the early 17th century was transporting much of Italy back to the Dark Ages, first with the Inquisition set up in 1542 and then shortly afterwards with the Index Librorum Prohibitorum which banned a wide array of Renaissance literature, including the entire works of over 500 authors. Humanism became heresy as did anything contradicting the Bible and if a writer was judged to have the wrong religious conviction then all of his works were banned.

The Index was strictly enforceable within the Papal States but elsewhere only if adopted by the civil powers, which unsurprisingly happened in many Italian states. Amazingly the Index did not effectively disappear until the mid 20th century making it very likely that this form of severe undemocratic censorship over so many centuries played a significant role both in retarding modernization and impeding the development of robust democratic institutions in heavily Catholic southern Europe. No coincidence perhaps that Italy and Spain both ended up under authoritarian dictatorships in the 20th century. Unfortunately for Galileo the Renaissance in Italy was well and truly over by the end of the 16th century and he was forced to navigate the dangerous waters of the Inquisition as best he could.

The author of Galileo Heretic, Pietro Redondi, was, and perhaps still is, a Professor of History of Science and wrote this book 40 years ago shortly after receiving his doctorate. His first chapter is not the most riveting introduction I’ve ever read and requires more than a little concentration because he uses these 27 pages to help the reader understand Galileo’s difficult position at the intersection of astrology, physics and theology. Those people who remember more of their school science classes than I do will perhaps find it less confusing. The good news is that it’s only 27 pages and in Chapter 2 the narrative improves as Redondi introduces us to the political atmosphere of early 17th century Rome; in successive chapters he describes the dominant underlying themes of that period which can be simplified and summarized as follows:

- Copernicus, Galileo and others versus Aristotle, Ptolemy and Catholic orthodoxy

- Galileo’s theory of ‘atomism’ versus ‘transubstantiation’

- Jesuit antipathy to Galileo

- Federico Cesi's Accademia dei Lincei and the search for scientific truth versus the Jesuit Collegio Romano, the Council of Trent and the Index.

Il Saggiatore

From 1616 onwards Galileo was a Copernican on strict parole, but though it was impossible for him to be a Copernican in his astronomy he was not forbidden to be Copernican in physics. Galileo’s most famous work, Il Saggiatore (the Assayer), published in 1623, was in many ways a natural progression from the work of Copernicus, Telesio, Bruno and others, all of whom had been condemned by the Inquisition.

That fact alone should have worried Galileo more than it did sitting contentedly in Florence, as should the fate of his admirer, Tommaso Campanella, a Dominican priest who wrote The Defense of Galileo while languishing in a Naples jail for decades, periodically tortured until finally restored to liberty in 1629 by the personal intervention of Pope Urban VIII, who apparently was in desperate need of Campanella's supposed magic skills to protect him from the dangers of two upcoming eclipses. Even Popes it seems were superstitious enough to hedge their bets.

Cardinal Bellarmino died in 1621 so was no longer the Chief Inquisitor when Marco Antonio de Dominis came before the court in late 1624 accused of heresy. De Dominis was no ordinary defendant; not only was he an archbishop, a scientist and an intellectual of European wide renown but he was in fact already dead and was brought before the court in his coffin where his 3 month old exhumed remains were in the advanced stages of putrefaction. His portrait was placed on the coffin (a nice touch!) and when the expected sentence was duly passed down the portrait, his coffin and all his books were taken to the Campo dei Fiori and burned. A less painful process for De Dominis than Bruno it has to be said.

One might be forgiven for thinking that Bellarmino’s tenure as ‘witchfinder general’ would have been quietly forgotten by the 20th century Catholic Church after the passage of several centuries, given that he was simply wrong in sentencing pioneering scientists and others to death. Quite the opposite in fact, for Bellarmino was canonized as a saint in 1930 and his was the portrait staring back at the author on a room on the first floor of the Palace of the Holy Office in June 1982 when Redondi was there to examine a new and mysterious document on Galileo.

The De Dominis affair represented a dark and sombre start to the new pontificate of Pope Urban VIII and reminiscent of a return to barbaric medieval times. It also represented yet another warning to Galileo but by then the Assayer was already in circulation.

Galileo's house in Costa San Giorgio, Florence
One of Galileo's houses in Florence, in Costa San Giorgio

In Chapter 6 the author brings Orazio Grassi to center stage, a Jesuit priest and talented mathematician but also someone with an axe to grind because in 1619 Galileo had ridiculed a lecture given by Grassi on the subject of comets that was subsequently published. Galileo wrote some quite insulting comments in the margin of his copy of Grassi’s lecture and in doing so he unwittingly created a powerful enemy whose published response to the Assayer in 2027 would come to worry and even frighten Galileo.

After his meeting with Bellarmino in 1616 Galileo had made sure to protect himself from condemnation with regard to Copernican astronomy but in his discussion of atomism (ie physical matter, light, shape and heat) he laid himself open to being accused of a heretical position with regard to one of the core beliefs of official Catholic theology, the ‘transubstantiation’. The subject of transubstantiation had been important in permitting Bellarmino to clear the path to a death sentence in the long trial against Giordano Bruno and while Grassi was busy ruminating on his response to the Assayer, it proved also to be the final proof of guilt against De Dominis.

This is the central contention of Redondi’s book and is largely based on the anonymous denunciation he found in the Holy Office that he attributes (with some persuasive reasoning) to Grassi. Unfortunately we then have to suffer through another chapter, this time mercifully only 24 pages, of mind-numbing theological disputes about the nature of the Eucharist before Redondi throws us some red meat in the form of a wider European perspective. As Redondi educates us on the significance of Protestant Sweden’s intervention in the Thirty Years War things start to make more sense.

In 1632, with the Swedish King in Bavaria at the heart of German Catholicism and poised to threaten Italy itself, the Spanish play hardball with the Pope and he is left with little choice but to let the Jesuits off their leash. Their target quickly becomes Galileo’s new book, The Dialogue, despite the fact that it had spent six years in pre-publication being vetted and corrected to ensure that it contained no surprises for his enemies.

The book was quickly put on the Index, along with all the rest of Galileo’s works, and banned (remaining on the Index in fact for the next 200 years) and the Pope’s previous friendship with Galileo could not survive the political expediency of the time and he was suddenly rendered helpless in the face of the ruthless orthodoxy of Galileo’s Jesuit enemies.

Galileo memorial in Arcetri, Florence

Galileo was condemned for Copernicanism (the official reason but, according to the author, not the real reason) and sentenced to penance and prison for life, but the Pope was then able to intervene and allow Galileo to return to Florence to serve out his sentence under house arrest in his own home, ‘the jewel’ in Arcetri (photos above and right).

A purge then followed to remove from Rome all of the actors in this drama, both Galileo’s friends and supporters and his enemies. Even Galileo’s great adversary Grassi was banished far away to his home town of Savona but 20 years later he returned under a new Pope, though chastened enough to still refuse to publish anything new.

The final closure on the dispute between the Catholic Church and Galileo did not come about for another 359 years when on October 31 1992, after a 13 year investigation into the Galileo case, Pope John Paul II gave a grudging half-hearted apology of sorts, stating that "the clarifications furnished by recent historical studies enable us to state that this sad misunderstanding now belongs to the past". Odd that the Catholic Church would choose Halloween to announce that Galileo was now 'not guilty' because October 31 was the date in 1517 that Martin Luther supposedly nailed his 95 theses on the door of Castle Church in Wittemberg, Germany and ruptured the Catholic Church for ever.


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