Galileo: The Galileo Mistake

One of those scientists born into the aftermath of the Reformation was Galileo Galilei of Florence, Italy. While his father encouraged him toward a study of medicine, Galileo’s true interests were in mathematics and natural philosophy.

Scientifically and technologically he is well known for his invention of the telescope based on Dutch lens development, observation of the Supernova of 1604, discovery of craters on the moon and four moons to the planet Jupiter and the invention of a mechanism to raise water to higher levels; using an inclined plane he demonstrated that all bodies fall at the same rate. He was the first to develop and utilize rigorous scientific experimentation procedures, once stating “Measure what is measurable, and make measurable what is not so.”

In 1612 he began to encounter decisive Roman ecclesiastical opposition to his theory of the motion of the Earth based on the Copernican hypothesis (i.e., the Earth is not immovable; it rotates around the Sun along with other planetary bodies).

Church officials believed it to be heresy because it seemed to violate the literal intent of such scriptural passages as Joshua 10:13 (“And the sun stood still, and the moon stopped,…..”), Psalms 93:1b (“He has established the world; it shall never be moved;”) Psalm 104:5 (“You set the earth on its foundations, so that it shall never be shaken.”). The Roman Catholic hierarchy urged Galileo to teach heliocentricity as hypothesis rather than as fact, attempting to give what they believed to be proper balance to all viewpoints then being considered in that day and time.

In 1632 he was summoned to Rome to defend his teachings before papal Inquisition judges; Galileo was recalcitrant in his position and was, then, “vehemently suspected of heresy (false doctrine)” and condemned to house arrest and cessation of publishing for the remainder of his life when he would not abjure (i.e., deny) his theory and teachings. Immediately after he mouthed a rejection of his teachings before the Church court, Galileo is reported to have whispered to himself “Epur si muove” (‘And yet it [the Earth] does move.’).

Galileo died under the Church’s edict in 1642, but not without having had a few of his later writings smuggled out of Italy by loyal students (e.g., his book Discourses on two new sciences was published in The Netherlands).

Although the sixteenth century has subsequently been tagged as the “Age of Genius,” it was also a time of interdisciplinary turmoil. The Inquisition and the Protestant Reformation had forever changed the manner in which religious representatives and theologians would dialogue among one another. This was true, as well, about the way in which those of religion would interact with others, including the emerging, curious thinkers and experimenters of science. The rift between religion and science would continue to wax and wane from this point in history on until well into the twentieth century.

Galileo on the Inquisition: “And who can doubt that it (The Inquisition) will lead to the worst disorders when minds created free by God are compelled to submit slavishly to an outside will? When we are told to deny our senses and subject them to the whims of others? When people devoid of whatsoever competence are made judges over experts and are granted authority to treat them as they please? These are the novelties which are apt to bring about the ruin of commonwealths and the subversion of the state.” (Written on the margin of his own copy of Dialogue on the Great World Systems.)

Galileo on God’s Creation: “And to prohibit the whole science would be to censure a hundred passages of Holy Scripture which teach us that the glory and greatness of Almighty God are marvelously discerned in all His works and divinely read in the open book of heaven.” (In his Letter to the Grand Duchess Christina of Tuscany, 1616).

Galileo Revisited

To commemorate the 100th anniversary of Albert Einstein’s birth, Pope John Paul II convened his Church’s Pontifical Academy of Sciences, the College of Cardinals and the Diplomatic Corps in Vatican City on November 10, 1979. The precipitating purpose for this gathering, according to John Paul II, was “that theologians, scholars and historians, animated by a spirit of sincere collaboration, will study the Galileo case more deeply…..”

In 1981 the Roman Catholic Pontiff created an ongoing commission to “coordinate the research of theologians, scientists and historians which would help to further clarify the events which occurred between Galileo and the Church and, more generally, the Ptolemaic – Copernican controversy of the 16th and 17th centuries in which the Galileo affair is situated.” While the commission was empowered to study the Galileo incident specifically, it also was given the authority by John Paul II to consider related issues having to do with exegetics (i.e., Bible interpretation and applicability to the Galileo situation), general culture, science and epistemology (the study of knowledge, its acquisition and its distribution), and history and jurisprudence.

After more than a decade of intensive work and dialogue, the commission made recommendations to Pope John Paul II. Then, on October 31, 1992, the Pope officially closed the work of the commission, declaring that the “church had erred in condemning Galileo Galilei in 1633 for asserting that the Earth revolves around the sun.”

Incidentally, something associated with the Galileo commission’s relatively brief work that continues to perform practical scientific functions is the Vatican Observatory. This astronomical observatory, started and funded by Pope Gregory XIII in 1582 (actually, before the Galileo controversy took place), originated in the Roman Catholic Church’s desire to be as scientifically accurate as possible at the time in order to reform the calendar. Although the location and the purposes for the Vatican Laboratory have changed over the past four centuries, it is still functioning as an interdisciplinary program between religion and science with facilities at Castel Gandolfo close to Rome, Italy. In cooperation with the University of Arizona in the United States, a second research center (the Vatican Observatory Research Group) was built and staffed in Tucson, Arizona and works collaboratively with staff at the Steward Observatory at the University of Arizona.

This in – depth, very successful undertaking on the part of theologians, scientists and historians has been indicative of the cooperation yearned for (and somewhat achieved) by concerned and informed persons and movements in the latter half of the twentieth century. The hope is that as many as possible will desire to imagine and, then, actualize increasing cooperation between religion and science.


Corbally, Chris, S.J. (1997, July 7). History of the Vatican Observatory and its Castel Gandolfo Headquarters. On the Vatican Observatory Web Site (

Brinton, Crane, John B. Christopher and Robert L. Wolff. (1967). The Inquisition/The Protestant Reformation. In A History of Civilization – Volume One. (pp.459-492). Englewood Cliffs, N.J.: Prentice-Hall, Inc.

The Galileo Controversy (religious tract). (1996). On Catholic Answers Website (

Gerard, John. (1913). Galileo Galilei. In The Catholic Encyclopedia. Encyclopedia Press, Inc. (On-line version 1996 at Catholic Encyclopedia Website –

Halsall, Paul. (1997). Galileo Galilei: Letter to the Grand Duchess Christina of Tuscany, 1615. On Modern History Sourcebook Website. Fordham University. (

The Holy Bible – New Revised Standard Version. (1990). Nashville: Thomas Nelson Publishers/Cokesbury.

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Newman, J.R. (1956). The World of Mathematics. New York.

O’Connor, John J. and Edmund F. Robertson. (September, 1998). Galileo Galilei. On The Mactutor History of Mathematics archive website (

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Westfall, Richard S. (1995).The Galileo Project Website of Rice University. Department of History and Philosophy of Science, Indiana University ( ).

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