This extra credit opportunity is worth 2 points of extra credit PER question on your Unit 3 Test on Friday March 7.
During the 17th century, European scholars increasingly tried to understand the natural world through science. Galileo Galilei was one of these scientists, and he is sometimes called the Father of Scientific Reason.
Geocentrism is a model that places the earth at the center of the astronomical system. In this model, other bodies in space orbit around the earth. Geo comes from the Greek word for earth. 2. Heliocentrism is a model that places the sun at the center of the astronomical system. In this model, other bodies in space orbit around the earth. Helio comes from the Greek word for the sun. 3. We know that the earth orbits the sun, which is at the center of the solar system. Across centuries some astronomers debated models of their known universes. We know that some early Greek and Indian astronomers challenged aspects of the heliocentric model. Some medieval Islamic and western European astronomers also raised doubts about the model. But in 17th-century Italy, people didn’t know that the solar system was but a tiny piece of a much larger galaxy and universe. In Galileo’s time and place, nearly everyone believed that the earth was at the center of the universe (geocentric model). Even very smart people did not believe the Earth orbited because they couldn’t feel it move.
The heliocentric model seemed to contradict the Bible. This passage from Joshua is an example: On the day the Lord gave the Amorites over to Israel, Joshua said to the Lord in the presence of Israel: “Sun, stand still over Gibeon, and you, moon, over the Valley of Aijalon.” So the sun stood still, and the moon stopped, till the nation avenged itself on its enemies, as it is written in the Book of Jashar.
Copernicus was one of the first medieval European scientists to challenge this idea, but he knew how radical his theory was, so he waited to publish his book until right before his death.
The Catholic Church convened the Council of Trent in 1545 to stop the spread of Protestantism and to revive the Catholic Church. The council decreed that only the Catholic Church could interpret the Bible and established the Holy Office of the Roman Inquisition to persecute heretics. A heretic is someone whose beliefs go against the Church’s official beliefs.
Giordano Bruno was another scientist who supported the heliocentric model. Additionally, he correctly theorized that the sun is just one of many moving stars and that the universe contained many planets orbiting other stars. In 1600 he was tried before the Inquisition and burned at the stake. We don’t know the exact charges he was found guilty of, and in addition to his astronomical theories, he held many religious beliefs contrary to the Church’s doctrines.
Galileo was born in Pisa, Italy in 1564. He was a religious man and even wanted to be a monk at one point. Instead, he studied motion and physics at the University of Pisa. The more he studied, the more he started to believe the heliocentric theory. In 1609, he built a telescope. The observations he made from the telescope convinced him that Copernicus’s heliocentric model was right, and Galileo and began teaching the model to his students.
In 1615, The Church warned Galileo to stop teaching the heliocentric model. In 1616, the Church banned the works of Copernicus and others that supported heliocentrism. Galileo continued to write and publish ideas about his theory. Pope Urban VIII told Galileo he could discuss Copernicus’s theory, as long as he didn’t say it was absolutely true. His 1632 book, Dialogue Concerning the Two Chief World Systems, came too close to arguing the theory was true, and he was brought before the Inquisition as a heretic the following year.
Central Historical Question: Was Galileo really a heretic?
Document A: Galileo’s Letter (Modified)
Galileo wrote the following letter to Duchess Christina of Tuscany in 1615. In this letter, he defends himself against the charges of heresy.
Some years ago I discovered in the heavens many things that had not been seen before our own age. The novelty of these things . . . stirred up several professors against me. They hurled various charges and published numerous writings filled with vain arguments, and they made the grave mistake of sprinkling these with passages taken from places in the Bible, which they failed to understand properly.
The reason given for attacking the opinion that the earth moves and the sun stands still is that in many places in the Bible one may read that the sun moves and the earth stands still. Since the Bible cannot err, it follows that anyone who claims that the sun is motionless and the earth movable takes an erroneous and heretical position.
With regard to this argument, 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. But I believe nobody will deny that the Bible is often very complex, and may say things which are quite different from what its bare words signify. . . .
I do not believe that the same God who has given senses, reason and intellect has intended us to not to use them. . . . He would not require us to deny sense and reason in physical matters of direct experience. . . . Can an opinion be heretical and yet have no concern with the salvation of souls?
Source: Galileo Galilei, “Letter to the Grand Duchess Christina of Tuscany,” 1615.
novelty: original or unusual
err: to be wrong
pious: devoutly religious
Document B: Cardinal Bellarmine
Cardinal Robert Bellarmine was in charge of dealing with difficult issues connected to the Church’s power and beliefs during the Galileo controversy. He wrote the following letter to Paolo Antonio Foscarini in response to Foscarini’s book defending Galileo. Historians don’t believe Bellarmine ever saw Galileo’s 1615 letter (Document A).
As you know, the Council [of Trent] prohibits interpreting the Scriptures contrary to the common agreement of the holy Fathers. And if you would read not only the Fathers but also the commentaries of modern writers on Genesis, Psalms, Ecclesiastes and Joshua, you would find that all agree in explaining that the sun is in the heavens and moves swiftly around the earth, and that the earth is far from the heavens and stands immobile in the center of the universe. . . .
It would be just as heretical to deny that Abraham had two sons and Jacob twelve, as it would be to deny the virgin birth of Christ, for both are declared by the Holy Ghost through the mouths of the prophets and apostles. . . .
I say that if there were a true demonstration that the sun was in the center of the universe and the earth in the third sphere, and that the sun did not travel around the earth but the earth circled the sun, then it would be necessary to proceed with great caution in explaining the passages of Scripture which seemed contrary, and we would rather have to say that we did not understand the Scripture than to say that something was false which has been demonstrated. But I do not believe that there is any such demonstration; none has been shown to me. . . . [One] clearly experiences that the earth stands still and that his eye is not deceived when it judges that the moon and stars move.
Source: Cardinal Robert Bellarmine, “Letter on Galileo’s Theories,” 1615.
contrary: against or the opposite of something
Genesis, Psalms, Ecclesiastes and Joshua: sections of the Bible
prophets: someone who speaks for God
apostles: religious messengers
scripture: text from the Bible
Document C: Condemnation of Galileo (Modified)
In 1632, Galileo, who had been teaching and writing about the idea that the Earth moved around the sun, was summoned to Rome to stand trial. After questioning the relevant witnesses, the judges issued the following condemnation of Galileo.
You, Galileo of Florence, were denounced in 1615, by this Holy Office, for holding as true a false doctrine taught by many, namely, that the sun is immovable in the center of the world, and that the earth moves . . . also, for explaining the Scriptures according to your own meaning. Therefore . . . by the desire of his Holiness and the Most Eminent Lords, Cardinals of this supreme and universal Inquisition, the two propositions of the stability of the sun, and the motion of the earth, were qualified as follows:
1. The proposition that the sun is in the center of the world and immovable from its place is absurd, philosophically false, and formally heretical; because it is expressly contrary to Holy Scriptures.
2. The proposition that the earth is not the center of the world, nor immovable, but that it moves is also absurd, philosophically false, and, theologically considered, at least erroneous in faith.
Therefore, in the most holy name of our Lord Jesus Christ and of His Most Glorious Mother Mary, We pronounce, judge, and declare, that you Galileo . . . have made yourself suspected by this Holy Office of heresy, that is, of having believed and held the doctrine (which is false and contrary to the Holy and Divine Scriptures) that the sun is the center of the world, and that it does not move from east to west, and that the earth does move, and is not the center of the world; also, that an opinion can be held and supported as probable, after it has been declared contrary to the Holy Scripture.
Source: “The Crime of Galileo: Indictment and Abjuration of 1633.”
condemnation: a statement of very strong criticism
scripture: text from the Bible
denounce: to declare something is wrong or evil
doctrine: a set of beliefs
eminent: distinguished, high in station
proposition: a statement expressing a judgment or opinion
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