Scientific Awakening--Galileo

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The towering figure in the Scientific Awakening was, without question, Galileo Galilei (1564-1642.) Born in Florence, he studied mathematics and then taught Euclid's geometry and Aristotle's astronomy and physics at the University of Padua for eighteen years (1592-1610). As early as 1598, however, in correspondence with Kepler, he secretly confided that he was a Copernican; in 1604, he began to lecture against the geocentric model (O'Connor and Robertson. "Galileo Galilei" 3). Like Kepler, he immediately recognized the importance of Lippershey's "spyglass," refined and expanded its capabilities, and pointed it towards the heavens. The conventional wisdom that heavenly bodies were composed of ethereal non-matter was about to "bite the dust." In The Starry Messenger (Siderus Nuncius,) published in 1610 (a year after Kepler's The New Astronomy,) Galileo "claimed to have seen mountains on the Moon, to have proved the Milky Way was made up of tiny stars, and to have seen four small bodies orbiting Jupiter" (O'Connor and Robertson. "Galileo Galilei" 4). Soon, he detected lobes (later to be identified as rings) on Saturn, the phases of Venus, spots on the sun. These findings, so at odds with conventional wisdom and Church tradition, brought Galileo to the attention of Pope Paul V and Cardinal Bellarmine. Both warned him, especially as Copernicus' heliocentric model of the universe was condemned a "foolish and absurd" heresy in 1616. (Linder 4) (The Galileo portrait at left was painted in 1636 by Justus Sustermans.)

(O'Connor and Robertson. "Galileo Galilei--Picture Gallery 1)
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5 minute Cloud bio of Galileo < >

As Galileo's observations and conclusions led him inexorably toward the dangerous ground of blasphemy and heresy, he nevertheless considered himself a loyal, devout son of the Church. He offered "infinite thanks to God for being so kind as to make me alone the first oberver of marvels kept hidden in obscurity for all previous centuries" (Linder 2). But since he could not keep his pen down or his mouth shut, he was on a collision course with the Church Militant of Pope Paul V and Cardinal Bellarmine. He argued, in Letters on the Solar Spots and in a letter to his friend and disciple Benedetto Castelli, that Scripture must be understood as truth in a figurative sense. Cardinal Bellarmine ("hammer of the heretics") admonished him to "relinquish altogether" his defense of heliocentrism (Linder 5) and the Holy Office proclaimed as dogma a stationary earth at the center of the universe (Copernicus, Kepler, and Galileo to the contrary nothwithstanding.) Paul V (1605-1621) met personally with Galileo and warned him. (see right for portrait of Paul V, née Camilo Borghese)

image source < >--gone


Robert, Cardinal Bellarmine (1542-1621,) a scholar, teacher, and devout Jesuit lived when the Counter Reformation was in full swing, and he devoted his considerable talents and energies to combatting heresy wherever he found it, especially as official papal theologian. As archbishop and cardinal, he dedicated his life to defending Catholic doctrine, including papal authority for Popes Paul V and Urban VIII during the Counter Reformation. It was Bellarmine who used the terms "foolish and absurd" to describe the Copernican "heresy." He said, at the height of the controversy, "To assert that the earth revolves around the sun is as erroneous as to claim that Jesus was not born of a virgin." The beatification of Bellarmine began in the 17th century; he was canonized in 1931 by Pope Pius XI (Van Helden 2).
A person of enormous stature in the Church, Bellarmine was chosen by the Holy Office to interrogate and admonish Galileo in 1615. Indeed, he threatened Galileo with harsh reprisals (dungeon? torture? death?) unless he renounced categorically the false propositions: the sun-centered universe; the moving (rotating/revolving) earth
(Meyer 2). Galileo retreated to Florence; at least he had not been ordered to halt his studies, only to desist from lecturing and/or publishing anything that might be construed as defending Copernicanism.

(graphic, Van Helden 1)
image source < http// >
site above gone, go to "The Galileo Project" < >

For several years, Galileo lived and worked in his observatory and laboratory near Florence. By 1623, his old nemesis Cardinal Bellarmine was dead. A new cardinal, Maffeo Barberini, ascended the papal throne as Pope Urban VIII (1623-1644.) Galileo hoped for new attitudes in the new papacy and resumed his astronomical research. He began the epochal Dialogue Concerning the Two Chief Systems of the World--Ptolemaic and Copernican, in Italian, framing his argument as hypothesis to get it past the papal censors. Galileo finished the work in 1629, revealing himself not only as a consummate scientist but as a sophisticated polemicist, and polished writer (Linder 5). Early permission to publish gave way to its suspension. In 1633, he was summoned to Rome to defend his masterpiece against Jesuits, the Holy Office, and Pope Urban VIII himself. The Church closed ranks against Galileo: Father Melchior Inchofer wrote of Copernicanism that it was "pernicious" and "scandalous," that it denied the "immortality of the soul" and the "existence of God" (Meyer 3). Urban VIII met on six separate occasions with Galileo, to no avail. Bernini painted the portrait of Urban VIII (right)

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At his trial, ten cardinals subjected the old man to endless questioning, always hanging over his head the threat of heresy and/or excommunication. Galileo renounced the Dialogue and recanted his belief in the whole apparatus of Copernicanism, confessing on June 22, 1633, "I affirm...on my conscience, that I do not now hold the condemned opinion.... I am here in your hands--do with me what you please." (Linder 7) He did not mutter to himself "And yet, it moves," though this legend has found its way into some history books. Galileo was too devout, too incontrovertably Catholic to have jeopardized his immortal soul in such a fashion. During the last nine years of his life, he consistently begged to be allowed to take the sacrament and to be buried in consecrated ground. He spent these last years under house arrest at his home, Arcetri, where he resumed his studies on terrestrial motion. Late in his life, as a very old man, Galileo prevailed upon Urban VIII to allow him to attend mass in a nearby church (Gingerich 19).

image source, Linder < >--gone

"Trial of Galileo" < >

Aside from his famous work in astronomy and epic confrontation with the Papacy and Holy Office, Galileo is as (if not more) significant for his defense of empiricism and his studies in mechanics, as physics was then called. Physics was considered to be the "queen of sciences." Galileo's theories on terrestrial motion were easily as epochal as his ones on the heavens. He dropped objects from great heights, he rolled objects on inclined planes, he measured their rates of acceleration. He discovered and formulated mathematical theories regarding moving bodies on earth, refuting the conventional and Aristotilean wisdom that heavy objects fall faster than light ones. Legend describes his experiment of dropping a 10 pound and 1 pound weight simultaneously from the "leaning Tower of Pisa." (Palmer, et al. 275-276) His principle of the pendulum enabled him (and other scientiests) to measure time more accurately. He developed the principle of inertia, though Newton explained it more thoroughly and accurately in his Universal Law. In Two New Sciences, with less verve and daring after the condemnation of the Dialogue, he returned to Salviati, Sagredo, and Simplicio to discuss mass and acceleration. (Sobel 307) Galileo demonstrated that a uniform force--gravity (though he did not name it)--produced uniform acceleration. (McKay, et al. 598) His "combination of experiment and theory, of action and mathematics, is the key to Western physics." (Teresi 194) Or, to put it another way, perhaps his greatest achievement was "the elaboration and consolidation of the modern experimental method." (McKay, et al. 598)

image source < >--nope

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for video on Galileo: Battle for the Heavens

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For more information on Galileo, visit
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Professor Emeritus of Astronomy and the History of Science at the Harvard-Smithsonian Center for Astrophysics,
Gingerich says,
"Galileo was the most articulate spokesman for the new astronomy, the pioneer who set
observational astronomy on its modern track. He simply had the misfortune to be born in the period when
the Reformation, the Counter Reformation and the Thirty Years' War greatly restricted his intellectual options


Background Image: Linder, Douglas. "Selected Images--Dialogue Cover." The Trial of Galileo. Online Available
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Annewein and Roman. "The Leaning Tower of Pisa." Annewein and Roman's Wedding Pics. Online Available

Galileo: Battle for the Heavens. PBS Production, 2003.

Gingerich, Owen. "Starry Messenger." The New York Times: Book Review.
27 December 2010.

Hathaway, William. "Paul V." St. Ed's Parish Servers News. Online Available
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McKay, John, et al. A History of Western Society, 6th ed. Boston and New York: Houghton Mifflin Co., 1999.

Knox, Skip. The Reformation. Online Available
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Linder, Douglas. The Trial of Galileo. Online Available
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O'Connor, John and Edmund Robertson."Galileo Galileo." The MacTutor History of Mathematics Archive. Online Available
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Palmer, R. R., et al. A History of the Modern World, 9th ed. Boston, et al.: McGraw-Hill, 2002.

Sobel, Dava. Galileo's Daughter. New York: Penguin Books, 2000.

Spielvogel, Jackson. Western Civilization, 4th ed. Belmont, et al.: Wadsworth/Thomson Learning, 2000.

Teresi, Dick. Lost Discoveries. New York, et al.: Simon & Schuster, 2002.

Van Helden, Albert. "Robert Cardinal Bellarmine (1542-1621.)" The Galileo Project. Online Available
< http// >


*Unfortunately, quite a few of the links and resources on this page have
flown away or been taken down by their authors...alas.

McKee, Peggy. "Galileo." The Scientific Awakening. Updated. January 13, 2015 . Online Available.
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(McKee. "Galileo")