Gavin Hoots, Grade 7
Galileo was a brilliant astronomer whose discoveries caused him great distress. He was also a man of Christian faith. Ironically, his greatest detractors were educated men in the Church, some of whom were Inquisition judges. Galileo was tried by the Inquisition after his book was published in 1632. The book was titled Dialogue Concerning the Two Chief World Systems. The controversy was over Galileo’s heliocentric cosmology, a conception of the solar system that contradicted the cosmology of Aristotle that was taught in the Catholic universities.
Galileo was born in 1564 in Pisa, Italy. He was the first of six children born to wealthy parents. His father, Vicenzo Galilei, was a lutist and a music theorist who encouraged his son to think about the world in mathematical terms, directing his son towards quantitative description of the results, or basically, the scientific method of experimentation and observation.
Galileo started his formal education in 1574 at the Camaldolese Monastery in Florence. Galileo found the monastic life attractive and he became a novice, but his father wanted his son to become a medical doctor. In 1581 Vincenzo sent Galileo back to Pisa where Galileo studied for a medical degree, but due to financial difficulties he left before earning his degree.
Galileo continued to study mathematics, supporting himself through minor teaching positions. During this time he began his study of objects in motion which he would continue for 20 years. This research led to the publication of The Little Balance, a treatise that brought him fame and gained him a teaching position at the University of Pisa in 1589. Soon after, he took a position at the University of Padua. This was fortunate for him, as his father died in 1591, leaving Galileo with responsibility to take care of his younger brother Michelangelo.
Galileo taught at the University of Padua for 18 years. His lectures were entertaining and drew large numbers of students, further increasing his fame and wealth.
In 1604 Galileo published The Operations of the Geometrical and Military Compass. He was 40 years old. That same year he refined his theory on motion and falling objects and came up with the universal law of acceleration. Before Galileo scientists thought that force causes speed, but Galileo showed that force causes acceleration. Galileo reached the conclusion that bodies fall on the earth at a constant acceleration, and that gravity, which causes all bodies to fall, is a constant force. In other words, a constant force like gravity does not lead to constant speed but to constant acceleration.
Galileo built his first telescope in 1609 after learning how Dutch eyeglass makers had built a simple telescope. He showed his apparatus to some merchants who recognized that it would be useful for spotting ships. The merchants paid him to manufacture several telescopes. In1610 Galileo used his telescope to observe the stars and planets. With the telescope he made discoveries that caused him to question Aristotle’s cosmology. He saw mountains and valleys that indicate changes on the moon. He observed the motion of four of Jupiter's moons. He also observed the phases of Venus, which could be explained only by the motion of Venus around the sun, not the Earth. He published his discoveries in a small volume titled The Starry Messenger.
Galileo understood the implications of his discoveries in physics and astronomy. He wrote,
“My purpose is to set forth a very new science dealing with a very ancient subject. There is, in nature, perhaps nothing older than motion, concerning which the books written by philosophers are neither few nor small; nevertheless, I have discovered some properties of it that are worth knowing that have not hitherto been either observed or demonstrated. Some superficial observations have been made, as for instance, that the natural motion of a heavy falling body is continuously accelerated; but to just what extent this acceleration occurs has not yet been announced... Other facts, not few in number or less worth knowing I have succeeded in proving; and, what I consider more important, there have been opened up to this vast and most excellent science, of which my work is merely the beginning, ways and means by which other minds more acute than mine will explore its remote corners.”
Galileo did not see a conflict between science and the Bible. He believed that both served God and made truth more evident to Humankind. He wrote, "God is known by nature in his works, and by doctrine in his revealed word."
In a 1615 letter to Madame Christina, the Grand Duchess of Tuscany, Galileo wrote, “I think in the first place that it is very pious to say and prudent to affirm that the Holy Bible can never speak untruth—whenever its true meaning is understood.”
Pope Paul V ordered the Inquisition to look into Galileo’s work. The Inquisition ruled against him in 1616.
One of Galileo’s friends, Cardinal Maffeo Barberini, was chosen to be the Pope in 1623. Galileo went to see him, but Urban VIII did not lift the injunction against him. Galileo received permission to write about both the Ptolemaic and the Copernican systems. He did exactly that in his Dialogue Concerning the Two Chief World Systems which was published in 1632. It was regarded as a literary and philosophical masterpiece, but it clearly favored the Copernican cosmology and this lead to further problems with the Church hierarchy.
Again, Galileo was called before the Inquisition in 1633. This time he was forced to renounce his findings and promised never again to write about the Copernican system. He was 70 years old and placed under house arrest. Galileo died on January 8, 1642, after suffering from a fever and heart palpitations.
Galileo’s final work was a volume that detailed his 30 years of work in physics. The book was titled Dialogue Concerning Two New Sciences and many scholars consider it his greatest work. This was written while he lived under house arrest. It was printed in Holland in 1638, but by this time Galileo had become blind from a combination of cataracts and glaucoma.
In 1758, the Roman Catholic Church lifted the ban on writings that supported the Copernican cosmology. By 1835 the heliocentric understanding of the solar system was accepted and taught in Catholic universities.
In 1981 a commission of the Church began to look into Galileo's case, and 11 years later the commission acknowledged that Galileo's judges had erred in their assessment. In 1992 Pope John Paul II acknowledged that the church was wrong to condemn Galileo.
Related reading: Galileo's Christian Faith