The Protestant Reformation was not the only challenge posed by the Renaissance to what I have called the “Medieval cathedral” of Europe. Humanism’s departure from a theocentric worldview delivered by the Church opened up an unfettered search for knowledge (in Latin, scientia), sparking the first run-ins between the teachers of Christian faith and those of science and broader secular philosophy.
In the middle of the 16th century and the beginning of the 17th, faith and rational scientific inquiry clashed as ecclesiastical authorities in Rome lined up on one side and two notable scientists and a theologian defended free thought. At the heart of the disputes that entangled Christianity in Rome, and later Protestantism, was a literal reading of the Bible, combined with the largely medieval conceit that Christian theology, then known as “the queen of the sciences,” could solve almost any puzzle the human mind could throw at it.
Nicholas Copernicus (1473-1543), a Polish polyglot and polymath, obtained a doctorate in canon law (he received minor orders and may have been ordained a priest) as well as advanced degrees in mathematics, astronomy and medicine. He was a classics scholar, translator, governor, diplomat and economist (who anticipated what came to be known as Gresham’s Law, the principle that “bad money drives out good”).
His major contribution was formulating the modern model of the universe, which places the sun at its center. Aristarchus of Samos had formulated such a model in ancient Greece, but writings on the subject were lost and unknown by the Renaissance, when most believed that the earth was static and the sun revolved around it. The significance to Christianity lay in the current reading of a passage in Joshua 10:12-14 concerning the defeat of the Amorites, as follows:
On the day when the Lord gave the Amorites over to the Israelites, Joshua spoke to the Lord; and he said in the sight of Israel, “Sun, stand still at Gibeon, and Moon, in the valley of Aijalon.” And the sun stood still, and the moon stopped, until the nation took vengeance on their enemies. Is this not written in the Book of Jashar? The sun stopped in midheaven, and did not hurry to set for about a whole day. There has been no day like it before or since, when the Lord heeded a human voice; for the Lord fought for Israel.Renaissance Christian scholars and theologians read the passage as implying that the sun and moon revolved around the earth. Arguing quite the contrary, Copernicus’ work De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres), published just before his death, triggered the Copernican Revolution, which in turn brought about the thinking that set off the Scientific Revolution.
Oddly enough, the immediate result of Copernicus’ book was only mild controversy. The Council of Trent discussed neither Copernicus’ theory nor the actual calendar reform it approved, which used tables deduced from Copernicus’ calculations. It was not until 60 years later that the Catholic Church took official action and only because of another genius, an Italian.
Galileo Galilei (1564-1642) was an Italian polymath, astronomer, physicist, engineer, philosopher and mathematician. He played a major role in the scientific revolution of the 17th century and has been called the father of observational astronomy, modern physics, the scientific method and science itself. He was a pious Catholic, but the three children—two girls and a boy—who made him an actual father were born out of wedlock.
Galileo, a professor at the University of Padua, took it almost as a dare when Bellarmine observed in 1615 that Copernicus’ system could not be defended without “a true physical demonstration that the sun does not circle the earth but the earth circles the sun.” Galileo thought his theory of the tides provided the required physical proof of the motion of the earth and said so in a work initially titled Dialogue on the Ebb and Flow of the Sea (the reference to tides was removed by order of the Inquisition, which retitled the work Dialogue on the Two Chief World Systems).
But he added to the theories a series of observations from a new instrument, the telescope, which he devised in 1609 drawing on work by a Dutch optician who had developed lenses that magnified the apparent size of remote objects. This allowed him to observe Jupiter's moons, Venus, Saturn, Neptune, sunspots, and the moon and to discover the Milky Way, which bolstered his theories on nearby earth.
Galileo’s defense of heliocentrism and Copernicanism flew in the face of what the learned of his day believed. They mostly held to the Ptolemaic earth-centered system supported by Aristotle. Alternatively, the Tychonic system, developed by Tycho Brahe, a Danish nobleman, combined the Copernican system with a philosophical and “physical” approach to the Ptolemaic system.
Facing opposition from astronomers, including Tycho, the matter was investigated by the Roman Inquisition in 1615. It deemed heliocentrism “foolish and absurd in philosophy, and formally heretical since it explicitly contradicts in many places the sense of Holy Scripture.” Passages at 1 Chronicles 16:30 (“the world is firmly established, it cannot be moved”), Psalm 104:5 (“the Lord set the earth on its foundations; it can never be moved” and Ecclesiastes 1:5 (“And the sun rises and sets and returns to its place”) were cited in support.
Speaking before the Inquisition, Father Niccolò Lorini accused Galileo and his followers of attempting to reinterpret the Bible, which smacked of Protestantism. At the start of 1616, Monsignor Francesco Ingoli launched a debate with Galileo by sending him an essay disputing the Copernican system.
In March 1616, the Sacred Congregation of the Index, established in 1571 to investigate writings denounced as containing errors, issued a decree suspending the late Copernicus’ De revolutionibus until it could be “corrected,” on the grounds of ensuring that Copernicanism, which it described as a “false Pythagorean doctrine, altogether contrary to the Holy Scripture,” would not “creep any further to the prejudice of Catholic truth.”
Galileo went to Rome to defend himself and his Copernican and biblical ideas. Bellarmine had the job of examining him, and their exchanges are a remarkable record of the controversy. The Jesuit, believed to have developed great compassion toward Galileo, was ultimately charged with delivering the verdict of the Inquisition in 1633.
Galileo was found “vehemently suspect of heresy” and required to “abjure, curse and detest.” Publication of his works was banned, and he was sentenced to prison. The sentence was reduced to lifelong house arrest, thanks, perhaps, to Bellarmine. Reputedly, Galileo submitted—but under protest. As related in a 1757 narrative in English, “The moment he was set at liberty, he looked up to the sky and down to the ground, and, stamping with his foot, in a contemplative mood, said, ‘Eppur si muove,’ that is, ‘still it moves,’ meaning the Earth.”
The third wrestle with scientific ideas was with those of the lesser known Giordano Bruno (1548-1600), an Italian Dominican friar, philosopher, mathematician, poet and cosmological theorist in the then-novel Copernican mold. He proposed that stars were just distant suns surrounded by their own exoplanets, raised the then-heretical possibility that these planets could even foster life, and insisted that the universe is infinite and could have no celestial body at its “center.”
Bruno was tried by the Roman inquisition beginning in 1593. He was charged with denying several core doctrines, including eternal damnation, the Trinity, the divinity of Christ, the virginity of Mary and transubstantiation. Bruno’s pantheism, reminiscent of the beliefs of the 20th century Dominican Matthew Fox—removed from the Catholic priesthood on similar charges—was also a matter of grave concern. The Inquisition found him guilty, and he was burned at the stake in Rome.
After his death, Bruno gained considerable fame, becoming celebrated by 19th and early 20th century rationalists as “a martyr for science.” However, historians debate whether his heresy trial was a response to his astronomical views or to other aspects of his philosophy and theology.
Unlike what happened with Copernicus and Galileo, Bruno’s case exemplifies the way, from Trent onward, the Catholic hierarchy put a tight lid on new ideas in a broad array of fields, with fateful consequences—including the relative underdevelopment of science, industry and wealth in Catholic countries over the next half millennium.