Everyone knows the church sent Galileo to the Inquisition for contradicting scripture by suggesting the Earth revolved around the Sun. The story is so well known that it is used as an abbreviation for the idea that religion is the enemy of science. “Yeah, well what about Galileo?” is often the unanswerable retort. What I love about any sentence beginning with “everyone knows” is that what everyone knows is usually far from accurate.
Take this idea that the Roman Church of the sixteenth century was trying to suppress the knowledge that the Earth orbited around the Sun. That becomes problematic when you consider that the church was not only the religious establishment of its day, but also the scientific establishment as well. As such, it may surprise you to learn that the church taught the very same theory in its own schools, albeit as hypothesis rather than fact. No one denied its usefulness and accuracy in computing the movement of the planets. You might also be surprised to learn that after Galileo was convicted by the Inquisition, the very same theory continued to be taught in those very same schools. That alone should be reason enough to indicate there was more to the story than commonly thought.
The chief reason heliocentrism was not accepted as fact was scientific rather than religious. It made a prediction that was observed to be false. If the Earth orbited around the Sun, it was expected that one should be able to observe a parallax shift in the star field as the Earth moved through its orbit. In other words, as the Earth swings from one side of the Sun to the other, you should be able to tell that you are viewing the stars from a different angle. Simple observation made it plain that wasn’t the case and it gave weight to the idea that the Earth was stationary. We understand today that the reason for not seeing this shift is the unimaginable distance to the stars. Because the stars are so far away, the tiny shift in angle from one position to another is too negligible to be observed. To the sixteenth century mind though, those distances were … well, unimaginable.
We also forget that much of what Galileo promoted as fact was wildly incorrect. He believed the Sun was the center of the universe. (Wrong.) He believed the planets orbited around the Sun in perfect circles. (Wrong again.) He believed that tides were the result of the oceans sloshing back and forth in response to the spinning of the Earth. (Hilariously creative, but wrong nonetheless.) All these erroneous ideas were part of what he stubbornly insisted should be accepted as fact. At the same time, he ridiculed the ideas of Johannes Kepler who advocated elliptical orbits for the planets and the moon as the cause of the tides. Kepler was right. Galileo was wrong.
None of this justifies Galileo being subjected to the Inquisition, but it does raise the question of how he got there. That seems best understood in terms of political infighting within a massive bureaucracy. Anyone with personal experience of how a bureaucracy functions knows there are always factions vying for power. Early on, Galileo was the fair-haired boy of the Roman Church. His work created excitement and brought him fame, honor and not a little money. Galileo himself wrote that the church was his greatest benefactor, but his success led to jealousy among his peers who found their life work being crowded out. They looked for a way to attack him and discovered they could assault him using scripture as a blunt instrument.
Now the issue of scripture was not insurmountable. As far back as the 4th Century Augustine wrote that biblical passages written as poetry or songs should not be taken as literal descriptions of history or science. This is certainly what Galileo believed and he had many powerful supporters in the church who agreed with him. Among his supporters was the cardinal who would later become Pope Urban VIII.
In 1615, the Inquisition investigated Galileo and decided that while his views were possible, because of the unanswered parallax question and other issues, they remained unproven. Therefore they ordered him to refrain from advocating his views as settled science. He could discuss them as possibilities, but not as fact. All things considered, the Inquisition arrived at a reasoned decision that was not far off the mark; and they did so without the use of torture. That too is surprisingly different from our modern idea of how this infamous court operated.
After being named Pope Urban VIII, Galileo’s friend urged him to write a book presenting both sides of the heliocentric argument. The new pope envisioned a fair discussion of the issues, but what Galileo produced not only violated the Inquisition’s order by blatantly advocating his own beliefs, but seemed set up to mock the pope himself as a simpleton. Galileo’s enemies convinced the pope that he was a threat to the authority of the church. Urban VIII was more than a little paranoid and insecure in his lofty position to begin with. Under the pressure of being perceived as weak, he reacted with predictable vehemence against his former friend. Galileo was sent back to the Inquisition where he was convicted of heresy, forced to recant and sentenced to house arrest for the remainder of his life. This happened to Galileo, in my opinion, not because his views contradicted scripture, but because he was so inept that he alienated practically everyone of authority in the Roman Church. His own bureaucratic bumbling brought about his downfall.
There is a popular story that while being accused of heresy Galileo begged a bishop to just look through his telescope and see the proof of what he said. As the story goes, the bishop’s mind was so closed that he would not even bother to look at the evidence. If there’s any truth to the story, I bet the bishop refused to look because he was trying to get a stubborn Galileo to understand that his problem wasn’t up in the heavens but here on Earth.