The Catholic Church and its Repression of Three Freethinking Scientists

Galileo Galilei - via Wikimedia Commons.

Autocracy, theocracy, and aristocracy have, for most of the Holocene, dominated human civilizations. From the ancient Egyptians to the Roman Republic to the French aristocrats to the German Nazis, a line of religious, spiritual and familial authorities have governed most of our historical societies. Few times – ancient Greece, the Roman Empire and some modern countries, to name most – have societies embraced even a limited form of democracy. 

In the many times that societies did not, scientists helped lead the rebellion: they promoted new ideas and changed the course of thought only through their discoveries. Some scientists risked even their lives in the inexorable pursuit of truth.

The Catholic Church has traditionally been a surprising proponent of scientific development: it has been a prolific financial supporter of schools, universities and research institutions, and even today it operates the iconic Vatican Observatory. Nevertheless, even despite an institution’s intense promotion of scientific inquiry, discoveries that contradict religious teachings will lead to hiccups. Here, let us consider three scientists – Giordano Bruno, Galileo Galilei and Cecco d'Ascoli – whose ideas and discoveries made them enemies of the Church.

Cecco d'Ascoli

First, we will begin with Cecco d’Ascoli, who is most famous for his alleged quarrel with the famous poet Dante, although whether this quarrel actually happened or not is disputed. d’Ascoli was a mathematician, astronomer and an astrologer – when astrology was considered a legitimate science.

d’Ascoli was born in Ancarano, in the modern-day region of Abruzzo, Italy. Any details on his early life are practically unknown, and even the date of his birth is unknown. Most of the information on his life comes from his famous quarrels with Dante and the Catholic Church, the latter of which led to his death.

d’Ascoli devoted his life almost exclusively to mathematics and astrology, and while there is no information on his education, he did become professor of astrology at the University of Bologna, which is the oldest active university in the world.

d’Ascoli is not known for any significant discoveries and advancements in astronomy, but he did write Acherba, a massive, unfinished poem and encyclopedia consisting of 4,865 verses of sesta rima – a six line stanza with an a-b-a-b-c-c format. It consists of 4 volumes: the first covers the astronomical and atmospheric sciences; the second discusses stellar influences (astrology), physiognomy, and vices and virtues; the third covers minerals and the love of animals; and the fourth submits and solves certain moral and physical quandaries.

Most of d’Ascoli’s experimentation followed practices similar to the modern scientific method, which led him to become familiar with metallic aerolites (debris from space-borne objects), shooting stars and meteors. He was also the first to explain dew and even the circulation of the blood, and he also observed the plant fossils deposited during mountain-forming revolutions on earth.

Despite the advancements he wrought, d'Ascoli’s free expression and critical rhetoric made him an unsurprisingly central enemy of the Church. In the early 1320s, d’Ascoli pushed an audacious theory that the theocracy employed demons, which led him quite quickly into trouble with the Clerical party. Surprisingly, his rhetoric was not met with edict that he be executed, but instead with fines and condemnations. Yet, unsurprisingly again, he fled the Church without paying his fines, and continued to reject many established institutions. Nevertheless, after an enemy of his, Dino di Garbo, pursued and caught him, he was tried and convicted of heresy and was burned at the stake the day after his sentence, at age 70. 

Giordano Bruno

Giordano Bruno was a Dominican friar, mathematician, poet, and cosmologist who advocated heliocentrism and rejected biblical inerrancy, a Church belief that the Bible is, by nature, without error. Bruno, too, was burned at the stake

Bruno was born in 1548 in Nola, a small town in the province of Naples, Italy. His father was a soldier, and his mother a caretaker. When he was young, he was sent to Naples, the city, to be educated. He attended private tutoring at the Augustinian monastery in Naples and attended public lectures in the city. At the age of 17, he took the name Giordano – after his metaphysics professor’s name – and entered the Dominican Order in a monastery in Naples. At the age of 24, he became an ordained priest. 

Bruno was an exceptionally intelligent person, as was obvious throughout his years in school and in his adult life, but he had one trait that the Catholic Church admonished: ostentatious free thinking and a thirst for forbidden knowledge. His free thinking led him on a life that led him slowly, inexorably, to the stake. It is nevertheless surprising that he still remained an ordained minister for eleven years, despite how different his religious beliefs and scientific opinions were to the Church’s.

Giordano Bruno was a proponent and early discoverer of a larger universe and a universe in which not Earth, but the sun is its center (in other words, heliocentrism), both of which are at least somewhat consistent with modern thought. 

Bruno was an avid and fierce proponent of heliocentrism. In 1584, he published two philosophical dialogues – La Cena de le Ceneri and De l'infinito universo et mondi – both of which accorded to and reaffirmed the Copernican theory of heliocentrism.

Bruno not only affirmed heliocentrism in his philosophical doctrine and scientific thought, but he also formulated theories regarding the size of the universe. A few of his original hypotheses surrounding astronomy included:

  • The universe is infinite in size and filled with a substance known as pure air, or the aether. This substance did not resist the momentum of the heavenly bodies.*

  • The points of light in the sky are actually extremely distant suns that produce light just as the sun does. The stars previously known as the fixed stars** were originally speculated by Bruno to be ultra distant stars that produce their own light and have their own planets orbiting them. 

  • Other worlds "have no less virtue nor a nature different from that of our Earth" and, akin to earth, "contain animals and inhabitants". In other words, the birth of astrobiology.

It is almost self-explanatory how Giordano Bruno’s speculation changed the scientific view of the world. Much of his original speculation is still core to current scientific thought – it is possible still that other star systems have worlds with animals and inhabitants, and it is now known that those fixed points of light are ultra-distant suns of their own.

Giordano Bruno’s trial is an obvious hint towards the Catholic Church’s resistance directed at heliocentrism and devotion towards a hierarchical universe dominated by earth, and thus, humans, alongside its commitment to a uniform system of religious thought. Some historians believe thatGiordano Bruno was denigrated and eventually tried by the Catholic Church for his speculation surrounding cosmology and astronomy, but some also believe that his religious thought – his belief in reincarnation and pantheism, for example – led to the charges. Bruno was charged for ten serious offenses, including, but not limited to:

  • Holding opinions contrary to the Catholic faith and speaking against it and its ministers.

  • Claiming the existence of a plurality of worlds and their eternity.

  • Believing in metempsychosis and the transmigration of the human soul (Christians universally rejected the belief in reincarnation and affirmed that a deceased person was sent either to Heaven or to Hell)

  • Dealing in magics and divination.

He was declared guilty for all offenses, and after seven years of trial and imprisonment, he was hung upside down and burned at the stake on February 17th, 1600, on Ash Wednesday.

Galileo Galilei

Galileo is certainly the most well known of the three scientists on this list, even though all contributed significantly even to modern scientific thought. Galileo is considered the father of modern science, the father of the scientific method, the father of observational astronomy, and the father of modern physics, and is often credited with the invention of the telescope. He is also considered the discoverer of Venus, Mars, Mercury, Jupiter, and Saturn. His imprisonment is the most famous story of historical persecution of scientists, and certainly the most famous imprisonment the Catholic Church ever made.

Galileo Galilei was born on February 15th, 1564, and died on January 8th, 1642, at the age of 77, quite old for his time. He died while serving life in home imprisonment by the sentence of the Church.

Galileo began his life in Pisa, Italy, as the first of 6 children under Vincenzo Galilei, a well known composer at the time. His father was imperative in Galileo’s scientific development: from a young age, Galileo was taught and eventually became a talented lutenist; he also learned from his father the value of quantified experimentation and the results expected from mathematics and experimentation. 

His father indoctrinated him with Catholic and otherwise accepted thought when he was a child, some of which Galileo rejected, kickstarting an inexorable focus on freedom of thought that Galileo would cherish until his death.

Galileo’s young education occurred between 1575 and 1578, from the age of eleven to fourteen. He later went to the University of Pisa to pursue a medical degree, which was, as I am sure you know, not his preferred path. Throughout his early adulthood, he had been kept out of mathematics in order to earn the job of a physician, which made more money. 

One day, however, he noticed that a chandelier was swaying back and forth at a similar rate to his heartbeat, which inspired him to devise an experiment in which he was to hit two pendulums against one another; he found that the two bounced off each other and back at each other in the exact same amount of time as the other. From this point, he became immersed in mathematics, and began to pursue natural science. He coerced his father into allowing him to work towards a career in science and natural philosophy.

Among the three scientists mentioned and described in this episode, Galileo made the most discoveries of them all. Galileo contributed a significant amount to many fields of science, rather than contributing a significant amount to a very narrow field of science, leading to his title as a polymath. He was responsible for discoveries in fields like astronomy, cosmology, mathematics, engineering, and many other fields. Among his contributions to the sciences and engineering are:

  • Upon observation of Kepler’s supernova, the conclusion that stars are exceptionally far away and that change had occurred to a star that had existed before; this hypothesis disproved the popular Aristotelian belief in the immutability of the heavens, or a stagnant universe.

  • The design of the first working telescope, which was significantly stronger than Lippershey’s Dutch Perspective Glasses. All of the following discoveries were made with his telescope.

  • The discovery of five planets: Jupiter, Saturn, Venus, Mars, and Mercury. 

  • The discovery of the four largest moons of Jupiter*** – Europa, Io, Callisto, and Ganymede.

  • The discovery of Saturn’s rings and the conclusion that Saturn and its rings were separate planets (the latter of which was later disproved by William Herschel).

  • The observation of Neptune, the most distant planet in the solar system. Because of its faintness, Galileo did not consider it a planet. He had accounted for its apparent movement through the sky relative to the other stars, but eventually lost track of the planet and could not find it again.

  • The discovery that the massive, hazy features of the Milky Way are actually densely-packed star fields. Before then, it had been believed that the Milky Way was a largely gaseous entity. 

  • The first observations of the sun and its sunspots. His discoveries of sunspots and the sun’s rotation further disproved the concepts of immutability and geocentrism.

Galileo, too, was a proponent of heliocentrism and a leading figure in its promotion to scientific merit. Many of his discoveries – including the discoveries of sunspots and the planets – only supported that Earth orbited the sun, rather than vice versa.

His methods of experimentation are still used today, and many of his discoveries are still important in science and engineering to this day. Consider the telescope: without Galileo, not only will we have lost the scientific advancement that came with Galileo himself, but we will also have lost, at least for some time, the powerful telescopes Galileo designed and used. Few scientists before Galileo made as many significant discoveries as he did. Galileo is certainly, as Albert Einstein once called him, “the father of modern science.”

Nevertheless, Galileo’s assertion that heliocentrism was the reality of the solar system was not taken lightly by the Catholic Church. The Church considered geocentrism a heavily implied concept in the Bible, as it often states Earth as unmoving. Heliocentrism counters an unmoving Earth, as it requires that Earth revolve around the sun (or, in other words, move).

In February 1616, the Church declared heliocentrism false – without evidence – and banned the publishing and printing of Copernicus’s De Revolutionibus, the central work supporting heliocentrism. Galileo generally avoided the controversy surrounding heliocentrism for around a decade; yet once a friend of his, Cardinal Maffeo Barberini, became the Pope, he released his discourse discussing the debate between geocentrism and heliocentrism, known as Dialogue Concerning the Two Chief World Systems. The novel portrays both sides of the argument, with the geocentrist interpretation displayed by a character named Simplicio, which Galileo derived from a notable Aristotelian philosopher. 

The Church, however, did not consider Simplicio a serious argument against heliocentrism, and despite the fact that Galileo genuinely sought to present a legitimate view presenting the debate between geocentrism and heliocentrism, the evidence was so overwhelming toward heliocentrism, that the Catholic Church considered the work to be in support of heliocentrism. As a result, the Church forced Galileo to defend his book on trial, and they eventually forced him to claim, despite the fact that he wrote it as an analysis of geocentrism and heliocentrism, that his piece was biased towards heliocentrism. 

Galileo was found “vehemently suspect of heresy,” or merely suspected – not convicted – of committing heresy. He thus avoided receiving capital punishment, but was sentenced to formal imprisonment; yet, because of his poor health, he was allowed to remain at home on house arrest for the rest of his life. While on house arrest, he published perhaps his most important piece, Two New Sciences, in which he accounted for the science he worked on forty years earlier, and explained the two new sciences as kinematics and strength of materials. He continued on in his work despite poor health and house arrest until his eventual death on January 8th, 1642

Wrapping it up

It is evident that the Church once fiercely rejected heliocentrism. From its proposition by Copernicus to its confirmation by Galileo, controversy surrounding it persisted. The Catholic Church did not consider the Bible erroneous, which was later disproved, at least to a degree. These scientists fought the fight against freethinking until the end, all in the name of science and the freedom of expression. While they may not be scientific martyrs, they certainly died for the causes of science, freedom and independence. As always, take care and stay curious, everyone.

* The aether actually was one of the most significant developments of sixteenth-century science, as the existence of an “aether” – whether as a propagator of air or light (see “luminiferous aether” in entries #30 and #31) – became the accepted idea (for over three hundred years) as to what composed the universe. 

** The five visible planets – Mercury, Venus, Mars, Jupiter, and Saturn – were the wandering stars, derived from the Greek word for wanderer, “planetes” (see entry #9).

*** Otherwise known as the Galilean moons.

If you have any questions, comments, or corrections, please comment on this post or email with your concerns. Thank you.


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