This Week in History

Eppur Si Muove! — Galileo Condemned: June 22, 1633

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Galileo Galilei

At times Galileo seemed quite a humble man. For instance, he wrote, “I have never met a man so ignorant that I could not learn something from him.” Yet, despite such statements, Galileo was proud and could be quite harsh with those who disagreed with him. Firmly convinced that his discoveries had proven that the Copernican heliocentric hypothesis was true, Galileo showed little patience with those who thought otherwise. For instance, writing in the margin of a book written to defend the Ptolemaic system, Galileo called the book’s author (the Jesuit Antonio Rocco) an “ignoramus, elephant, fool, dunce.”

But though he had little respect for Rocco, Galileo was on good terms with other Jesuits—at least for a time. Jesuits had been among the foremost scientists of Galileo’s day. The Jesuits in Rome were quite interested in Galileo’s discoveries. In 1611, they welcomed him to Rome and allowed him to stay in their house in the city. What’s more, Church prelates and Pope Paul V himself showed the astronomer every sign of favor.

Christoph Scheiner

What then happened to sour Galileo’s friendship with the Church? As we have seen, it was churchmen who urged Copernicus to publish his work, and churchmen (particularly the Jesuits) who were eager students of natural science and had made important scientific discoveries themselves. (For instance, the Jesuit Christoph Scheiner of Ingolstadt had discovered sunspots in 1611, about the same time Galileo himself did.) Why, then, did churchmen, and the Jesuits in particular, become Galileo’s opponents?

The reason is that Galileo and the churchmen differed in how they understood the importance of Copernicus’s ideas. Even the most scientific Jesuits thought Copernicus’s heliocentric idea was a hypothesis, and only a hypothesis. That is, they thought the heliocentric idea might be a useful instrument to help astronomers describe the universe and make predictions about when solar eclipses and other phenomena would occur. The Copernican hypothesis was a good tool, they thought, but it did not necessarily describe the universe as it truly is.

Title page to Copernicus’s On the Revolutions of the Heavenly Spheres

Churchmen—and, indeed, many of the most learned men of Europe — continued to hold to the notion that the Earth does not move and is the center of the universe. They thought the idea that the Earth moves and the Sun is stationary contradicted common sense. More important, they thought it contradicted Sacred Scripture, which in some places seems to say very clearly that the Earth does not move. Finally, in Galileo’s day, Copernicus’s hypothesis had not been thoroughly proven. There were still good reasons to think it might be a false way of describing the universe.

Galileo thought differently. He was convinced that his discoveries proved that Copernicus’s hypothesis was true, and he would not rest until he convinced everyone else of it as well. He even began to suggest ways to interpret the Bible to take care of the troublesome passages that seemed to say the Earth is stationary. Some churchmen thought Galileo was going too far in insisting on the truth of the Copernican hypothesis (and interpreting Scripture), and an intemperate Dominican named Tommaso Caccini began calling the Copernican system a heresy. Caccini tried unsuccessfully to get the Holy Office of the Inquisition in Rome to try Galileo as a heretic. Galileo was merely told to insert some lines into his works saying that the Copernican theory was a hypothesis. And when Galileo refused to do this, the Holy Office seemed not to care.

For his part, however, Galileo would not let the matter drop. Fearing further investigations by the Holy Office, he went to Rome in late December 1615. In Rome, Galileo approached various Church authorities, trying to convince them about the truth of his and Copernicus’s ideas.

Finally, in late February 1616, after Galileo and his ideas had become the talk of Rome, the Holy Office took action. On March 5, it issued a decree calling the Copernican view “foolish, philosophically false, and utterly heretical, because contrary to Holy Scripture” and commanded Galileo to reject the heliocentric theory and teach it no longer. Another decree forbade anyone to read Copernicus’s work until it was corrected. The Holy Office called for the removal of nine sentences from Copernicus’s book, On the Revolution of the Heavenly Spheres, that referred to the heliocentric view as a fact and not merely as a hypothesis. The Holy Office approved the publication of the corrected text of Copernicus’s work in 1620.

Urban VIII

Galileo agreed to obey the Holy Office and returned to Florence. For seven years, he carried on his researches and studies. Then, in 1623, Galileo learned that Cardinal Barberini had been elected pope as Urban VIII—news that filled the astronomer with hope, for Barberini had been one of three cardinals in the Holy Office who had opposed silencing Galileo in 1616. Galileo was able to meet with the new pope, hoping he would remove the Holy Office’s decree. Urban did not do this, but three years later the pope permitted Galileo to publish a work comparing the Ptolemaic and Copernican systems. Galileo had only to present the Copernican system as a hypothesis, not as fact, said the pope. To this, Galileo agreed.

This work, published in 1632, was written in the form of a dialogue (conversation) between three men. Two of the men, who defended the Copernican ideas, were presented as clever, insightful, and intelligent; the one who defended the Ptolemaic theory was presented as a fool, and was even called Simplicio—“simpleton.” Worse yet, Simplicio gave arguments that were very similar to the ones Pope Urban VIII had used in defending the Ptolemaic system to Galileo. Upon learning of all this, Pope Urban ordered the Holy Office to examine the dialogue. In August 1632, the Holy Office forbade any further sales of the dialogue, and in September Galileo was ordered to present himself for trial.

Galileo before the Inquisition, an 1857 painting by Cristiano Banti

The now aged Galileo appeared before the Holy Office in February 1633 and was charged with having broken his word by publishing a work presenting the Copernican system as true. Galileo said he was innocent; but he had to remain in the palace of the Holy Office, where he was well treated and lived in comfort, for the next several months. Finally, after several hearings, the Holy Office declared on June 22 that Galileo was guilty of heresy and disobedience. Kneeling, he had to declare that Copernicus was wrong, that the Sun is not the center of the universe, and the Earth does not move. He was then sentenced to be imprisoned and ordered to pray the seven penitential psalms once a week for the next three years. According to a later legend, as Galileo left the tribunal of the Holy Office, he muttered to himself, Eppur si muove!—“But it [the Earth] does move!” Whether he said this or not, Galileo despite his recantation, still held to the Copernican view that the Sun, not the Earth, is the center of the universe.

Galileo’s “imprisonment” in the palace of the Holy Office lasted three days more. By order of Pope Urban, he was then moved to a rich villa and from there to comfortable quarters belonging to a friend in Siena. Finally, in December 1633, he was allowed to return to his own villa near Florence. There he spent the remaining years of his life, receiving visitors, studying, teaching, and writing books. Galileo died at the age of 78, in 1642.

A portrait of Galileo painted by Domenico Cresti Passignano (1558-1638)

Since the 17th century, many have used the trial of Galileo to attack the Catholic Church. Protestants, for instance, have said the Holy Office’s condemnation of the Copernican theory disproves the Church’s teaching that the pope is infallible. Yet, what these critics miss is the fact that neither in 1616 nor in 1633 did the pope sign the decrees condemning the Copernican viewpoint. And even if the popes had signed the decrees, such decrees do not qualify as infallible teaching, as defined by the Church.

More serious, however, has been the charge that the Church persecuted Galileo because she is opposed to science and progress. Such a charge is unhistorical. As we have seen, far from opposing natural science, the Church in the 16th and 17th centuries actively supported it. In condemning Galileo, the Holy Office was not condemning science but what its members thought was a viewpoint that contradicted Sacred Scripture. And it is important to recall that Galileo was wrong to think that he had proven the Copernican view of the universe to be true.

Still, the trial of Galileo continues to this day to be used as an example of how the Catholic Church opposes science and human freedom. Beginning in the 17th century, many scientists and thinkers would adopt this false notion about the Church and come to think that all religion stood in the way of human progress. The story of Galileo’s trial thus came to symbolize for many the rebellion of the “modern,” scientific mind against what they saw as the ignorance and superstition of the Catholic Church and all traditional religion.


Music for the 1633 Roman Carnival

The baroque composer, Michelangelo Rossi, was born in Genoa. In 1633, while living in Rome, he composed the opera Erminia sul Giordano, which was first performed at the carnival that year. Here is the sinfonia from that opera, performed by Ensemble Il Falcone.