Saturday, February 20, 2010

Galileo's Trial: a battle between science and religion?

Post #4

Galileo’s Trial

Seven years later Galileo’s old friend and admirer Cardinal Barberini became Pope Urban VIII. Urban VIII and his leading academic officials thought very highly of Galileo’s books, and promptly invited Galileo to come visit. During the visit Galileo brought up the idea of his being able to continue writing about cosmology and the question of Copernicanism. Urban VIII, having studied astronomy himself, appreciated the mathematical prowess of Copernicus. Urban did not think Copernicus’ theory to be true, but considered it a useful contribution to astronomy nonetheless. He told Galileo he could resume his writing, provided that he treated Copernicus’ theory as an unproven hypothesis (which, we must remember, it was).

Galileo immediately set to work revising parts of old manuscripts to create a new book on the arrangement of the universe. He wrote the book as a dialogue between three men in which they discuss the merits of the Ptolemaic and Copernican systems. Framing the content in this way, Galileo hoped the discussion could stay at the needed theoretical level, avoiding any direct claims of the truth of Copernicus’ theory. Galileo worked on this book for many years, during which Pope Urban VIII decided to grant Galileo a yearly pension from the Church, merely for being such a valued intellect.

When the book was finally finished in 1630, Galileo sought permission to publish the book and submitted it to the relevant church authorities. It passed inspection with only a few minor changes needed, but due to the plague and other complications the book did not end up being published for another two years. When it was finally published, it became an instant success, selling out wherever it was printed. Cardinals, bishops, and Jesuit academics from all over wrote to Galileo of their praise and awe for his masterpiece, The Dialogue Concerning the Two Chief World Systems.

Unfortunately for Galileo, the publication of the Dialogue would also result in a trial in front of the Inquisition and being sentenced to house arrest for the rest of his life. Historians suggest that things would have been very different had Galileo or Copernicus lived one hundred years earlier or later. As it happened, several factors came together in precisely the wrong way for Galileo.

First, it was clear to readers of Galileo’s Dialogue who the victor was in the conversations and arguments concerning geo- and heliocentrism. The person arguing for geocentrism was named Simplicio and was clearly on the losing end of the argument. Galileo’s enemies within the church suggested to the Pope that Galileo was mocking the Church and him personally. While it is doubtful that this was the case (plenty of Church academics greatly enjoyed the book), these insinuations came to Pope Urban VIII at exactly the wrong time.

Urban VIII was a different person than he had been at the beginning of his office. He had made many political enemies around Europe, was involved in several wars, and feared attacks from Spanish assassins, among other concerns. Urban VIII also faced harsh criticism from Rome itself, accusing him of not taking a strong enough stance in defending the Catholic faith in the international arena. His paranoia and concern for his image resulted in determined anger and outrage, “especially if one is opposing, threatening, or defying him,” wrote a friend of Galileo’s who was close to the Pope. When Urban VIII heard remarks “insisting Galileo had played him for a fool by allowing Simplicio to espouse Urban’s philosophy,” he ordered an investigation into Galileo’s most recent work. The three person team told Urban VIII that, in their opinion, Galileo’s work was in fact an argument for the truth of Copernicanism. Urban was furious and summoned Galileo to stand trial before the Inquisition.

Galileo, almost 70 years old at this point, dutifully travelled to Rome to stand trial in 1633. Despite the portrayal of Galileo’s trial one sees in paintings, he stood before only two officials and a secretary. A full record of the transcript still exists (one can find them reproduced in Dava Sobel’s excellent Galileo’s Daughter), and the text is largely concerned not with “science” versus “religion” but with whether Galileo violated the earlier command from 1616 to not teach or write about Copernicanism except as a hypothesis.

But there was a problem: the official records of the Church concerning the incident in 1616 used stronger language then what Galileo had understood from Bellarmino. Galileo was under the impression that he was not to teach or write about Copernicanism as if it were literally true; according to the official records, he had been told not to teach or write about it at all. This came as a surprise to Galileo (and to Urban himself), and is still something of a mystery for historians today. It is possible that Galileo misremembered the original event, or that there was a miscommunication between the Inquisition and Bellarmino about the verbal injunction that had been served to Galileo (some have suggested that the Inquisition forged the document, but contemporary historians consider this unlikely). In any event, the Inquisition considered their own official records to take precedence over Galileo’s memory and letter from Bellarmino and found Galileo “vehemently suspected of heresy” and condemned to “formal imprisonment.” His Dialogue was also added to the Index of Prohibited Books, where it remained until 1835.

Later accounts would say that Galileo was jailed and even tortured, but in fact, after being forced to renounce his belief in Copernicanism, he was “imprisoned” in a sympathetic Cardinal’s palace for 5 months, and then allowed to return home to his villa near Florence. He lived out the rest of his life there, under what we would now call house arrest, with limited visitors and even more limited mobility for Galileo himself. He was crushed by the verdict and sentence, but, in a testament to his resilience, still produced and published (outside of Rome) what is probably his most important book, Discourses and Mathematical Demonstrations Relating to Two New Sciences. This book is considered foundational to modern physics and set the stage for the great scientists of the Enlightenment. Galileo died in 1642 at home, one of the most important intellectuals in history and a figure that still dominates discussion of science and religion today.


While this episode is unquestionably and unequivocally an embarrassment for the Catholic Church, it is also just as clearly not a simple case of science and religion coming into conflict. As we have seen, geocentrism was entrenched in the academy as well as within the Church and there was no clear evidence at the time to support heliocentrism over geocentrism. The main issues seemed to be Church politics (e.g. the Counter-Reformation) and scriptural interpretation rather than scientific progress. The Church was essentially acting as a political body, concerned with its own authority and power. We also must remember that Church is hardly alone historically in initially resisting new ideas. In addition, Galileo did have plenty of supporters within the church, including high ranking Cardinals, priests, and Church academics who clearly saw no conflict between religious faith and scientific discovery. Galileo himself was a devout Catholic who, along with almost every other major scientist in history, including Newton, Copernicus, Kepler, Pascal, Boyle, and Linnaeus, to name a few, saw the universe as being the handiwork of God and saw no conflict between their faith and scientific discovery (indeed, scientists like Kepler saw their scientific work as part of their worship and praise for God and his creation).

It is simply not the case that “religion” has any in-principal conflict with “science.” Have religious claims and scientific claims at times clashed? Absolutely. Have political/religious institutions hampered the publication of scientific work? Yes, they have. Is this the whole story? Not even close. The interactions of science and religion are many and complex, but one thing is for sure: the simplistic “warfare thesis” we have inherited from Huxley, Draper, and White must be discarded. Using their writings and revisionist history, one could argue that science and history are in conflict…

Previous Posts in the Series: Post #1, Post #2, Post #3

For further reading:

Science & Religion, edited by Gary B. Ferngren, John Hopkins University Press, 2002

Galileo’s Daughter, by Dava Sobel, Penguin Books, 2000

Making Modern Science: a historical survey, Bowler & Morus, University of Chicago Press, 2005

Galileo's Trial: a battle between science and religion?

Post #3

So we have seen in posts one and two some corrections to a few common myths surrounding the Copernican Revolution. Geocentrism, for example, was not a Christian idea but a Greek one adopted by the church. Also, the contrast between geocentrism and heliocentrism, which was proposed by Copernicus, a devout Catholic, cannot be seen as a contrast between science and religion because Copernicus did not have any scientific evidence for his views.

Now we come to the main event: the trial of Galileo. This episode has come to symbolize the conflict between science and religion, specifically between the Christian church and Western science. My intent in this post is not to defend the medieval Christian church or its behavior. There are dark spots in the church’s history, and I have no interest in pretending otherwise. Rather, I intend to show what contemporary historians have discovered upon a closer look at the trial of Galileo: that it was a complicated affair that cannot be reduced to a battle between science and religion.


Galileo Galilei was an Italian philosopher and mathematician who was born in 1564 and passed away in 1642 at the age of 78. A full history of his life and interactions with the church is impossible in a blog post, but I wish to focus on a few important points.

First, Galileo was a brilliant philosopher and scientist, as well as a devout Catholic. He is rightly regarded as the father of experimental science, being among the first to insist on empirical work in scientific investigation rather than reasoning from first principles as was standard in universities at the time. Galileo’s brilliance and willingness to question accepted wisdom brought him both international acclaim and some enemies in the academic and religious establishments.

Galileo first garnered international acclaim through the publication, in 1610, of his book The Starry Messenger, which contained the newfound astronomical knowledge he gained through use of telescopes he designed himself. This new knowledge included the discovery of the four moons around Jupiter, new stars, and the fact that our Moon had craters and valleys. This last bit was interesting because within Aristotelian natural philosophy, then dominant, everything in the heavens was perfectly spherical and smooth. Galileo did not hesitate to proclaim these new discoveries, but some devoted Aristotelian academics refused to acknowledge his work (some even claimed that the images seen in Galileo’s telescopes were illusions or tricks).

Contrary to the impression one might get from the standard story, Galileo gathered many friends and admirers within the church. He was befriended by Father Clavius, a leading Jesuit astronomer and the chief mathematician of the Collego Romano, a church institution which endorsed Galileo’s work and joined him in studying the heavens. Even Pope Paul V and Cardinal Barberini (the future pope Urban VIII) became fans, and Barberini a personal friend, saying to Galileo, “I pray the Lord God to preserve you, because men of great value like you deserve to live a long time to the benefit of the public.”

It is worth noting here that there were many university academics who objected to Galileo’s work and many within the church who embraced it. There is more to the story here, but in short Galileo’s disregard for academic tradition (i.e. Aristotelianism) earned him some enemies within the academy and, eventually, in the church as well.

Science and Scripture

Copernicus’ book which proposed the heliocentric (sun-centered) theory, De Revolutionibus, had been published in 1543, some 60 years before Galileo’s Starry Messenger. The heliocentric theory had never caused an uproar; many academics and theologians thought it interesting, a few embraced it as literally true, and others ignored it. Part of the reason for this was that at the time mathematics and astronomy were considered to be concerned with “appearances.” For example, as long as an astronomical theory could, say, accurately predict the motions of stars and be useful to navigators, it did not matter whether the theory was physically true. Part of Galileo’s legacy would be to elevate mathematics and astronomy out of the realm of “appearances” and into natural philosophy proper. This change, however, was difficult for his contemporaries to accept.

Galileo had embraced the heliocentric theory by at least 1597, but it was after he became famous in 1610 that his views on the matter became more widely known. In both public dialogue and a few published letters, Galileo made clear his preference for Copernicus’ heliocentric theory over Ptolemy’s geocentric one. This became one point among many for sharp disagreement between Galileo and other prominent university academics. Galileo appears to have had a gift for making enemies, for he applied his brilliance not only to academic topics but also to decimating and humiliating those who publicly disagreed with him. Within the church, also, there began to emerge some people who thought Galileo to be a problem, a mathematician encroaching too far into the domain of the philosophers. A priest friend alerted Galileo that a “certain crowd…put their heads together in a mad quest for any means by which they could damage you.” For those within the church who disliked Galileo, his heliocentric leanings provided a good target for them to attack.

As we have seen, geocentrism was the dominant cosmology and had been for centuries. While there were exceptions, most people at this time thought that both natural philosophy (science) and scripture supported an earth-centered universe. Scriptural passages such as Psalm 19:4-6 and Joshua 10:12, where Joshua commands the Sun to hold still, were seen to support a stationary Earth. This idea, that Holy Scripture supports the Ptolemaic geocentric universe, would prove to be central in the trial of Galileo.

The Catholic Church at this time was recovering from the sudden loss of power and authority caused by the Protestant Reformation, which began in 1517. In 1545 the Council of Trent had declared, among other things, that only popes and bishops were allowed to interpret Scripture. Galileo’s enemies, then, could cast his espousing the heliocentric theory as being against Holy Scripture. They did exactly that, and attracted the attention of the Pope, who ordered Cardinal Bellarmino, an important Jesuit intellectual, to look into whether Copernicanism might be heretical. Bellarmino was an admirer of Galileo’s work, but was skeptical of heliocentrism and believed that it did contradict scripture. The Catholic Church had a long history of distinguishing between literal and figurative language in the Bible, but, due to the Reformation and the Council of Trent, Bellarmino was obliged to defend the current interpretation of the church fathers. The Catholic Church was in an extraordinarily defensive frame of mind, and in the words of historian Richard Blackwell, “[I]t was in no mood to adopt a new and revolutionary model of the heavens.”

This was especially true since neither Copernicus nor Galileo had offered clear evidence for their views. Galileo went to Rome to argue his case, but his main piece of evidence was an erroneous theory of his about the cause of the tides. His other astronomical observations cast doubt on some of Aristotle’s claims about the heavens (e.g. their immutability) but failed to comment on the truth of the heliocentric versus geocentric theories. Since both natural philosophy and scripture appeared to support geocentrism, Bellarmino sided with tradition, seeing no good reason to do otherwise. In March of 1616 a formal proclamation was issued, declaring the Copernican position to be “false and contrary to Holy Scripture” and De Revolutionibus was ordered to have a few passages “corrected.” Bellarmino had a private meeting with Galileo to give him a warning to only treat Copernicanism as a hypothesis, but did not put any restrictions on his published works.

Gossip and rumors spread by Galileo’s enemies suggested that Galileo had been denounced and forced to repent, but Cardinal Bellarmino wrote a public letter declaring otherwise, and the Pope even met with Galileo to assure him that he had their full support against his slanderers. Even so, Galileo took the warning seriously (as the Church had meant it seriously) and was quiet for many years in his public affairs concerning the arrangement of the universe.

Next Post: Galileo's Trial

Galileo's Trial: a battle between science and religion?

Post #2

The Copernican Revolution

In the first post in this series, we covered the standard story of the Galileo Affair and discussed one of its flaws. In this second post we will look at a few more.

In 1543 a specialist in Catholic law who dabbled in astronomy on the side published a book called De Revolutionibus Orbium Coelestium (On the Revolutions of the Celestial Spheres). Nicolas Copernicus had been working on his book for several decades, and in it he laid out a new cosmology. The standard cosmology, as we have seen, was geocentric or earth-centered. Copernicus departed from this and instead proposed a sun-centered (or heliocentric) universe where the planets revolved around the sun. Though it was slow to start, the publication of De Revolutionibus would lead to a paradigm shift in cosmology known as the Copernican Revolution.

In the standard story, it is common for the Copernican Revolution to be cast as a battle between science and the Church or between reason and dogma. Copernicus was the brave rational soul who dared to defy those stuffy Christians and their religious dogma.

In fact, as we have already noted, Copernicus himself was a Catholic who specialized in canon law. The very source of the Copernican Revolution was a Christian who believed the universe was the handiwork of God. Copernicus also appears to have had some strong Neo-Platonic sensibilities. He had an almost mystical reverence for the Sun, and his motivation for proposing the heliocentric theory appears to have largely been due to his philosophical preference for simplicity and mathematical harmony. Ptolemy’s geocentric theory, while elegant, was extremely complicated. A common myth is that as time had elapsed since Ptolemy’s day astronomers had needed to add more and more epicycles (a feature of his model) in order to make sure Ptolemy’s model matched up with astronomical observations. The myth continues that Copernicus, realizing the evidentiary problems with the Ptolemaic model, took the needed theoretical leap to a new model. In fact, no new epicycles had been added, as Ptolemy’s theory was not easily modified. Indeed, Copernicus actually did not have any evidence, astronomical or otherwise, to support his model over Ptolemy’s. The heliocentric model, as proposed by Copernicus, was not any more accurate than Ptolemy’s (a testament to Ptolemy’s genius). Instead, it satisfied Copernicus’ devotion to mathematical harmony.

Copernicus’ theory did not stem from scientific observations but from his philosophical (and even mystical) preferences. We have already seen that geocentrism was not a product of religious dogma, but of Greek philosophy. Therefore the idea that the Copernican Revolution was a story of reason versus dogma or science versus religion is false.

But did Copernicus have to battle the Christian Church? Let us look at how the Church responded to these ideas.

First, we need to realize that there was no monolithic Christian response. It was certainly not the case that Christians in general rejected Copernicus’ ideas. In fact, several bishops of the Catholic church had written to Copernicus to encourage him to publish his work (this is before De Revolutionibus was published), thinking he would make a valuable contribution to astronomy. On the Protestant side, Lutheran scholars were responsible for finally convincing Copernicus to publish his book, helping him to do so. Afterward, Lutheran universities became the central institutions teaching heliocentrism.

Copernicus himself died within a few weeks of his book being published, and contrary to what one sometimes reads, was never persecuted by anyone. The initial response overall was rather muted, with many scholars, both Catholic and Protestant, thinking that the heliocentric theory was interesting but not clearly superior to Ptolemy’s model. A few key thinkers, Kepler and Galileo among them, did embrace the heliocentric theory wholeheartedly, eventually leading the latter into conflict with the Catholic Church.

It would be almost one hundred years, though, from the publication of Copernicus’ book in 1543 before the Catholic Church would add De Revolutionibus to its index of prohibited books. At first, some thinkers within the Church embraced the book’s ideas and others ignored it, but some within the Church began to build a resistance to the heliocentric theory that would culminate with the trial of Galileo. This is a complicated episode in the history of science which we will attend to in later posts. To close this post, though, let us compare how new theories have usually been received throughout the history of science. A major component of the standard story is the suggestion that religious belief is an especially potent force against new scientific theories. No doubt religious belief did play some role in the Church’s official rejection of heliocentrism (more on this later), but just how well do new theories usually do?

In 1915 Alfred Wegener proposed his new theory of continental drift. Did the scientific community welcome him and his new knowledge? Wegener was ridiculed (viciously) by the geological community, despite having some notable evidence for his views. As we have seen, Copernicus didn’t have any new evidence. Wegener’s theory was only accepted some 20 years after he died. This was in the 20th century and did not involve the church.

Einstein’s work on special relativity was largely ignored for several years. It was only when Max Planck, a giant in the field, started paying attention to Einstein’s papers that his theory got any traction. The theory was revolutionary, and therefore a tough sell for most scientists.

The big bang theory, now the standard model, was rejected or ignored for decades by the scientific community (in fact, some of the more zealous secular astronomers rejected it as being religiously motivated, but that is a story for another post).

Alexander Fleming made advances in proper medical treatment of deep wounds having to do with a correct understanding of the role of bacteria. The scientific medical community rejected his work, and many World War I soldiers died needlessly.

Thomas Kuhn’s work on paradigm shifts within science is well known. A dominant paradigm in science is difficult to overturn. A prominent scientist (I cannot recall who) was once asked how it is that new theories become accepted. The answer was something along the lines of: the old scientists die out and the new ones grow up to be more accepting of it.

Rejecting or resisting new theories is clearly not unique to the church.

Next post: Galileo’s Trial

Galileo's Trial: a battle between science and religion?

Post #1

The Standard Story

One of the most famous episodes in the history of science and religion is the Copernican Revolution, which began with the publication of Copernicus’s book in 1543 and culminated with the trial and conviction of Galileo in 1633. It did not end there, but that is as far as we will go in this series.

The standard story goes something like this: medieval Church doctrine held that the Earth was at the center of the universe, as it should be, since this is the most privileged location in the universe and Earth, being the home to mankind, is the most important planet. Copernicus and other scientists like Bruno and Galileo challenged this doctrine with scientific evidence showing that in fact the Sun was in the center. The Church, furious that scientific progress was being made (progress which challenged its own doctrines), persecuted these brave souls who dared give voice to reason and evidence. In short, this episode is an archetypal example of the conflict between science and religion.

I cannot recall how many PBS or Nova TV specials have been aired on the trial of Galileo, pitting Galileo the brave scientist against the oppressive anti-science Church. This version of the story is simply assumed by a great many people. For example, in an article for Slate magazine, Nathan Myhrvold wrote:

“Ptolemy (second century) was the first and boldest in a long succession of spin doctors for the primacy of human beings. The whole universe, he postulated, rotated around us, with the Earth sitting at the center of heaven itself. Any marketing consultant will tell you that positioning is everything, and center-of-the-universe is hard to beat. A Polish astronomer named Copernicus (1473-1543) rudely pointed out: Sorry earthlings, we spin around the sun, not vice versa…Bruno's crime, like Galileo's, was to undermine the uniqueness of our planet, and by doing so, to threaten the intellectual security of the religious dictatorships of his time. People get cranky when you burst their bubble. Over time, advances in astronomy have relentlessly reinforced the utter insignificance of Earth on a celestial scale. Fortunately, political and religious leaders stopped barbecuing astronomers for saying so…”

Slate magazine, a well-respected publication, is part of the Washington Post and has associations with National Public Radio. The standard story, however, as well as Mr. Myhrvold’s particular version of it, contains serious historical errors. Historian Richard J. Blackwell writes, “An oversimplified and false view is that Galileo became a martyr of science because of the Roman Catholic Church’s opposition to science, but it is now commonly agreed that the facts are quite otherwise.”

This will be the first in a series of posts intended to correct this common, but false, view of the Copernican Revolution.

Geocentrism and Greek Philosophy

The first myth we will tackle is the idea that geocentrism (the belief that Earth was at the center of the universe and everything revolved around it) was a Christian doctrine that entailed believing the Earth was special. In fact, geocentrism was an idea from Greek philosophy, not the Church. The Greeks devoted a lot of time to pondering the nature and structure of the universe, or cosmology. The geocentric theory was developed according to reason, evidence, and philosophical principles, not religious dogma or a special view of humanity. The geocentric model of the universe inherited by the medieval Church was the culmination of careful Greek thought, with Aristotle supplying the metaphysics and Ptolemy the mathematics. Ptolemy’s geocentric model was a masterpiece that matched up very well with astronomical observations. This model was adopted by Church scholars as well as by practically all the natural philosophers (i.e. scientists) of the time.

The geocentric view did not entail thinking the Earth was special. When Mr. Myhrvold, quoted above, asserted that the Earth was thought to be “at the center of heaven itself,” he could not have been more wrong (though at least he acknowledged the Greek origins of geocentrism). Within Aristotelian cosmology, Earth was thought of as corrupt and base, while the heavens were perfect and, well, heavenly. A more accurate description of Earth’s status at the time is that it was seen as the garbage dump at the bottom of the universe. Things were thought to fall to Earth because they were “heavy” and corrupt, and the Earth was the designated place for such unworthy things to fall. Indeed, Galileo saw his own work as elevating the status of Earth, not demoting it, writing:

“For I will prove that the earth does have motion, that it surpasses the moon in brightness, and that it is not the sump where the universe’s filth and ephemera collect.”

Next post: The Copernican Revolution

Saturday, February 6, 2010

Review of Christianity, Climate Change, and Sustainable Living

description of the photo

Christianity, Climate Change, and Sustainable Living is a relatively small book that tackles a broad range of issues. As the title states, the authors cover everything from the science of climate change to the appropriate Christian response to climate change. They also offer some practical advice to help both individuals and communities live more sustainably.

Though the flow of the book suffers a little due to the wide range of topics that are covered, I think the book is successful on all fronts. The summary of climate change is concise and accurate, giving a good overview of past, current, and projected future climate change and its many effects on our planet. I especially like how the authors frame anthropogenic climate change as a "reckless experiment." This is an appropriate way to think about climate change because, though the authors do not mention this, this century might be the first time that CO2 emissions have risen far ahead of temperatures (ice core records indicate that, in the past, the temperature changed first, followed by changes in CO2 levels). While we have sophisticated computer models that can project future changes based on current levels of knowledge, by emitting large amounts of greenhouse gases we are essentially taking part in a global experiment with a complex, poorly understood climate system. This fact alone should be enough to warrant caution when it comes to our fossil fuel use.

After laying out the evidence for the reality and potential severity of climate change and its effects, the authors turn to the question of how Christians should respond. Their answers are both wide-ranging and compelling. Through a much-needed evaluation of our unsustainable (and unhealthy) consumer culture, a Biblically-based call to take care of God's creation, and a reminder of God's charge for us to care for the poor (who will be most affected by climate change), the authors articulate a vision of a total Christian response to climate change. They cast this response as an important part of bringing God's kingdom to Earth. As Christians we are familiar with the spiritual aspects of the transformation of old to new, but Spencer, White, and Vrobleskly challenge us to think about how this applies to the whole of God's creation.

Also integrated into the book are plenty of practical principles to help guide our response, updates on national and global policies, quick analyses of alternative energy sources, and a helpful list of Christian organizations devoted to realizing the vision of responsible, sustainable living.

Christianity, Climate Change, and Sustainable Living is being published in the U.S. by Hendrickson and can be found here. Christians looking for a substantive, thoughtful response to the often heated (and politicized) issues regarding climate change and what to do about it need to read this book.