Galileo vs. the Catholic Church
Turning Point in History
The Conflict
In 1616, Galileo was
investigated by the
Roman Catholic Church,
which was very powerful
in Europe at the time. In
a formal Inquisition, a
kind of trial, Galileo was
ordered to stop
discussing ideas that
conflicted with the
teachings of the Church.
Ideas that conflict with
An engraving depicting Galileo Galilei (1564–1642) being
religious teachings are
tried by the Catholic Church. He was convicted of heresy for
called heresy. Heresy was
publicizing his belief that Earth revolves around the sun.
against the law and
punishable by
imprisonment or death. Religious leaders felt that questioning the Church and its
religious authority could lead to people giving up religion. Religion helped keep
order in society by setting social and moral expectations for behavior. Without
religion to give people guidance, church officials feared society might fall apart.
They believed that heresy was evil. Galileo was ordered either to stop supporting
a heretical theory or to be put in jail. What was Galileo saying that was so
dangerous? What led to this Inquisition?
Galileo Takes on Aristotle
The Greek philosopher Aristotle lived almost 2,000 years before Galileo’s time,
but his ideas were still believed by many, including theologians of the Catholic
Church. A theologian is someone who studies religion. One of Aristotle’s accepted
beliefs was that there were two kinds of matter, celestial and terrestrial. Celestial
means “of the heavens,” and terrestrial means “of the earth.” This would mean
that planets, stars, and moons—the celestial bodies—were all different from
Earth, the terrestrial body. These two kinds of matter each had their own
particular kind of motion. This belief in different kinds of matter led over time to
the belief that Earth is the center of the universe and that all celestial bodies orbit
Earth.
The view that Earth was the center of the universe was important to the Catholic
Church because they believed that Jesus, the son of God, was human and lived on
Earth. Such an important person could only live in the most important place—the
center of the universe around which everything revolves. It is important to note
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Galileo vs. the Catholic Church
Turning Point in History
that these theologians did not know that the universe is made up of billions of
galaxies. They thought that the solar system we live in was the whole universe. So
when they referred to the universe, they really meant only our solar system.
Galileo did not agree that our universe is geocentric, or that everything revolves
around Earth. It took him many years to figure out why Aristotle was wrong,
though. He also had a theory that all matter was the same and that there was only
one kind of motion.
In 1609, Galileo began working on his own version of a very recent invention, the
telescope. By 1610, he had not only developed his own telescope but had
published a book about his observations using it. In Starry Messenger, he
describes mountains on the moon as being like European mountains. He also
notes his discovery that Jupiter has four moons orbiting it, just as Earth has one
moon. In other words, he found that Earth is not so different from other planets.
Another book in 1613, Letters on the Sunspots, brought him two steps closer to
his big discovery. First, he observed sun spots, which appeared to move. Galileo
realized that the sun must rotate, which would explain the apparent movement of
the spots. Second, he oberved that Venus rotates around the sun.
Was the universe heliocentric, meaning that it revolved around the sun? If the
heliocentric theory was true, it would mean that everything revolves around the
sun, not Earth. It also would mean that Earth moves, too. If so, this would be a
tremendous change in the way people view the world. The idea had been
proposed before by Nicolaus Copernicus in 1543. Copernicus’s book, Revolutions
of the Celestial Spheres, was not widely read, and the Catholic Church was not
particularly alarmed by it. Members of the Church believed that the theory was
fine as long as it stayed a theory that scientists discussed among themselves. But
Galileo believed he had made progress in proving that the theory was true, and he
began to promote the theory. In 1611 he presented his arguments to Pope Paul V,
who treated him respectfully. With this encouragement, Galileo grew bolder and
more insistent that Earth revolves around the sun. This led to his trial at the
Inquisition of 1616 noted previously. Galileo obeyed the church precept, or order,
to end all discussion on the matter. But after 16 years, he published a book that
the Catholic Church could not accept at the time.
The Conflict Deepens
Galileo’s 1632 Dialogue of the Two Chief World Systems not only supported the
Copernican view that Earth orbits the sun, it also seemed to make fun of the
Catholic Church. The dialogue took place between three characters. Salviati
argued the Copernican view and represented Galileo. Sagredo was intelligent, yet
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Galileo vs. the Catholic Church
Turning Point in History
without specialized knowledge to give an opinion. Simplicio, who represented the
Church, argued the Aristotelian view that the sun orbits Earth. Simplicio was
characterized as “simple,” or not very intelligent. Because he represented the
Church’s view and teachings, depicting him as the loser in the debate offended
the Church. There was still another offense. Galileo wrote this book in Italian
instead of Latin, which
made it available to
everyone, not just
scholars. The Church
saw this as a direct
violation of the
Inquisition and
ordered him to travel
to Rome.
By now Galileo was an
old man and in poor
health. Making a long
journey was very
difficult for him. On
Church of Santa Croce in Florence. The floor contains
June 22, 1633, Galileo
many tombstones, and impressive monuments around the
knelt painfully before
sides celebrate important Renaissance figures such as
the panel of judges to
Michelangelo, Dante, and Galileo.
receive his verdict. He
was convicted of
heresy. To avoid being tortured, he recanted, or took back his claim that Earth
orbits the sun. There is a famous legend about what happened next, although
there is no historical evidence to support this story. It is said that as he got up
slowly from his kneeling position, Galileo whispered, “E pur si muove.” In
English, this mean, “And yet, it moves.”
Despite recanting, Galileo was given a life sentence of house arrest, and his books
were banned. Yet he continued working, questioning, and discovering from his
home. He secretly published another book on physics that contained some of his
most important ideas yet. He died on January 8, 1642, but his interaction with
the Catholic Church did not end with his death. In 1737, Galileo was reburied in
Catholic sacred ground at Santa Croce Cathedral in Florence after having been in
an unmarked grave after nearly a hundred years. Ninety-nine years after Galileo’s
death, in 1741, Pope Benedict XIV lifted the ban on Galileo’s books. In 1758, the
Catholic Church formally decided that saying the Earth revolves around the sun
was not heretical.
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Galileo vs. the Catholic Church
Turning Point in History
Healing the Rift
In 1992, Pope John Paul II formally pardoned Galileo, saying that the church had
been wrong to punish him. An official Church committee had done a 13-year
investigation into the conflict between Galileo and the Church. Some call this the
most important conflict between faith and science in history. Galileo’s work
marked an important turning point in two ways. First, he helped changed the way
we view Earth and our role in the universe. Second, he helped change the Church,
and his views eventually led to the Church being more accepting of scientific
thought. Though it took until long after his death, Galileo was finally understood.
He was not a man against the church—he was a church-going scientist. Galileo
and the Church finally found harmony, almost 400 years after the conflict began.
After reading the passage, answer the following questions:
1. Which term describes an idea that conflicts with the teachings of the
Church?
A. heresy
B. recant
C. Inquisition
D. heliocentric
2. Who proposed the theory that there are two kinds of matter, celestial
and terrestrial?
A. Galileo
B. Aristotle
C. Simplicio
D. Copernicus
3. In addition to publishing heretical views and poking fun at the Church,
in what other way did Galileo offend the Church?
A. by recanting his views
B. by writing his books in Italian
C. by rejecting Copernican theory
D. by not being a Roman Catholic
4. Galileo’s views caused him many conflicts with the Catholic Church.
According to the passage, why was saying that Earth revolves around
the sun a problem for the Catholic Church? Use details from the
reading passage in your answer.
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