Galileo's Inquest Begins: The Church Confronts Science

Galileo Galilei stood before the Roman Inquisition on April 12, 1633, charged with heresy for arguing that the Earth revolves around the Sun. The 69-year-old astronomer, already frail and partially blind, had been summoned to Rome from Florence after publishing his Dialogue Concerning the Two Chief World Systems, a book that transparently mocked the geocentric model endorsed by the Catholic Church. Pope Urban VIII, who had once been Galileo's friend and patron, took the mockery personally. The scientific case was already settled among informed astronomers. Galileo's telescopic observations, published in 1610, had revealed Jupiter's moons, the phases of Venus, and the craters of the Moon, all evidence that contradicted the Aristotelian model of a perfect, Earth-centered cosmos. But the Church had declared heliocentrism heretical in 1616 and had personally warned Galileo not to advocate it. His Dialogue, structured as a debate between a heliocentrist and a geocentrist named Simplicio, barely disguised which side Galileo favored. The trial lasted from April through June. The Inquisition's case rested not on science but on obedience. They produced a document, possibly forged, claiming Galileo had been explicitly ordered in 1616 never to teach or discuss heliocentrism. Galileo's defense was that his book presented heliocentrism hypothetically, not as established fact. Under threat of torture, he recanted, reportedly muttering "Eppur si muove" ("And yet it moves"), though this famous line is almost certainly apocryphal. Galileo was sentenced to house arrest for the remainder of his life, which he spent at his villa near Florence continuing his research in mechanics. His Dialogue was banned, remaining on the Index of Prohibited Books until 1835. The trial became the defining symbol of the conflict between scientific inquiry and religious authority. The Catholic Church did not formally acknowledge its error until 1992, when Pope John Paul II declared that Galileo's judges had made a mistake.