The trial of Galileo before the Roman Inquisition is perhaps the most distorted episode in the history of science and religion. This three-part series of posts addresses the myths, complexities and lessons we can learn from Galileo’s trial. The focus on the trial, what was really at stake, was the authority of the Catholic Church. Galileo’s challenged the Church and the nearly unanimous scientific consensus of his time.
Turning from the outright myths we will now address the complexities of Galileo’s conflict with the Church. These can be broken down into two categories. First, there are four factors, not generally understood from a modern perspective, which prevented the acceptance of heliocentrism. Second, there is a fundamental misconception about the nature of Galileo’s confrontation with Church.
The first problem that prevented widespread acceptance of heliocentrism was that the evidence available at the time was not sufficient. The modern view of heliocentrism is in light of what we know from science rather than what was known or could be proven during Galileo’s time. The arguments Galileo marshaled at the time supported the heliocentric view, but they were also compatible with the model put forward by Tycho Brahe. Galileo was convinced that the hypothesis of heliocentrism was true, but there was not enough evidence to overturn over 300 years of adherence to Aristotelian cosmology.
Second, if the task of overturning Aristotle’s long-established cosmology was not herculean enough, Galileo’s undertaking was seemingly made impossible by his arrogant and impulsive demeanor. He was typically far more effective at making enemies than converts. It is assumed by many experts on Galileo’s trial that his fate was in some sense made certain by the various enemies he had created in the years leading up to 1633. David Lindberg concludes, “Galileo’s personality was a consistent and important factor; indeed, it seems clear that had he played his cards differently, with more attention to diplomacy, Galileo might have carried out a significant campaign on behalf of heliocentrism without condemnation.”
A third impediment Galileo faced was the issue of epistemological authority. Where does knowledge of the cosmos come from? Is it available via human capacities of sense and reason? Is it only found in the scriptures? Is it some combination of the two? The prevailing view of both Catholic and Protestant theologians was that knowledge of the heavens was, in principle, unavailable to the natural sciences. The nature of the celestial realm was divine knowledge that was inaccessible to the human intellect. Thus, the work of Copernicus and Ptolemy were merely models used to predict the locations of the planets, they were mathematical instruments and not intended as descriptions of reality. Galileo’s argument regarding heliocentrism went far beyond a debate about which model was more accurate. He believed that the heliocentric model of the universe was a description of reality. Thus, he defied conventional wisdom not only about the inaccessibility of the heavens; he also claimed that scientific observation could attain knowledge not available from the Bible.
Fourth, the argument for another epistemic authority collided, rather violently, with the Catholic Church’s stance, after the Reformation, on the interpretation of scripture. One of the decrees issued by the Council of Trent (1545 – 1563) on the interpretation of scripture said in part:
The Council decrees that, in matters of faith and morals …, no one, relying on his own judgment and distorting the Sacred Scriptures according to his own conceptions, shall dare to interpret them contrary to that sense which Holy Mother Church, to whom it belongs to judge their sense and meaning, has held and does hold, or even contrary to the unanimous agreement of the Fathers.
Galileo’s two-books inspired reasoning was not without support within the Church, however the Decree issued in 1616 that heliocentrism was “contrary to Scripture” was a clear and convincing indication that the Church was going defend its authority on matters related to cosmology.
Besides the obstacles that prevented acceptance of heliocentrism, the Galileo affair is treated simplistically as a conflict between scientific rationalism and religious doctrine. In response to this assertion, consider the following: every one of the participants in this debate were Christians who accepted the authority of the Bible, were theologically informed, and could make rational arguments for their respective views on cosmology. Further, within the Church itself there were various opinions on hermeneutics, some agreed with Galileo, others did not. From the domain of science, among the experts in astronomy, heliocentrism was not a widely held view. In short, rather than a confrontation between science and religion, it might be more accurate to describe the Galileo affair as a conflict within science and religion.
In light of all this, what really happened? Simply put, it was a confrontation over the authority of the Church, not a scientific debate. Considering the Church’s stance on who may interpret scripture and Galileo’s temperament arguing for heliocentrism, a collision was inevitable. David Lindberg offers the following one sentence summary, “The trial was about disobedience and flagrant insubordination: the issues dealt with in the decree of 1616 were not reexamined; its conclusions were merely reasserted.” The merits of Galileo’s arguments were insignificant when contrasted against centuries of consensus. The authority of Aristotle’s geocentric cosmology was not going to be discarded simply because the heliocentric view was plausible. The Church chose to stake its authority on that consensus and science suffered as a result.
Finally, let us consider what lessons can be drawn from the Galileo affair. When studying history, one must always be careful not to fall into the trap of anachronism, judging events in the past through the lens of the knowledge and sensibilities of the present. When considering the heliocentric debate in context, the evidence available, and the consensus of the time, it was reasonable to support the geocentric view. Another form of temporal snobbery we should avoid is condemning the Church for how it exercised its authority. Lindberg makes the following observation about that period:
“The early seventeenth century was a time of growing absolutism in Europe, in both religious and political terms. The freedom to express dangerous ideas was as unlikely to be defended in Protestant Geneva as in Catholic Rome. The idea that a stable society could be built on general principles of free speech was defended by nobody at the time; and police and judicial constraints were therefore inevitable realities.”
Another important lesson is to eschew stark, simplistic contrasts regarding such broad categories “science” and “religion.” Such conflicts are rarely as simple as the contrast between truth and error; rather they are proxies for more subtle discussions. In this case, the issue of epistemological authority was at work. It was not merely a question of how things are known (mere epistemology) but what would be considered as a source of knowledge (authority). The Church sought to defend its interpretation of the Bible as true and correct in all “matters of faith and morals.” The mistake we perceive looking back is extending such control over matters of cosmology.
In our modern era it is widely believed that we have developed to a stage where what is actually true or false dictates what is considered knowledge. We believe we are no longer at the mercy of any bureaucracy or human institution to gain knowledge. In the 17th century, the Bible was the dominant source of knowledge about reality. What we have seen in this series is that Galileo was tried not for rejecting the Bible but for challenging the Church’s sole authority to interpret the Bible. Today, the Church (Protestant and Catholic) has been eclipsed by science as the preeminent (or perhaps only) source of knowledge for mankind. In reality however, the Church and institutional science have merely switched roles over the last 350 years. Today, the fields of science that attempt to explain the origins and development of life are trapped in a dogmatic devotion to an idea imagined over 150 years ago. Despite an overwhelming body of evidence to the contrary, neo-Darwinism is adhered to dogmatically as the only explanation for the development of life. As discussed in the film Expelled and numerous intelligent design blogs, advocating dangerous ideas that contradict the reigning consensus is punished, not with torture or imprisonment, rather the destruction of academic careers. Perhaps that is the strongest lesson we can learn from history; it always repeats itself.
 In Brahe’s model of the solar system, the earth was still at rest with the sun in motion around the earth, however all the planets orbited the sun.
 Lindberg and Numbers, When Science and Christianity Meet, 57.
 Ibid., 45.
 Ibid., 58.
 Ibid., 54.
 Ibid., 59.