People/Galileo Galilei
Galileo Galilei
Galileo di Vincenzo Bonaiuti de' Galilei, commonly referred to as Galileo Galilei or simply Galileo, was an Italian astronomer, physicist and engineer, sometimes described as a polymath. He was born in the city of Pisa. Galileo has been called the father of observational astronomy and known for modern-era classical physics, the scientific method, and modern science.
Galileo Galilei was not necessarily named after his ancestor Galileo Bonaiuti. The Italian male given name "Galileo" (and thence the surname "Galilei") derives from the Latin "Galilaeus", meaning "of Galilee", a biblically significant region in Northern Israel. Because of that region, the adjective galilaios means "Galilean", was used in antiquity (particularly by emperor Julian) to refer to Christ and his followers.
The biblical roots of Galileo's name and surname were to become the subject of a famous pun. In 1614, during the Galileo affair, one of Galileo's opponents, the Dominican priest Tommaso Caccini, delivered against Galileo a controversial and influential sermon. In it he made a point of quoting Acts 1:11, "Ye men of Galilee, why stand ye gazing up into heaven?"
Galileo's championing of Copernican heliocentrism was met with opposition from within the Catholic Church and from some astronomers. The matter was investigated by the Roman Inquisition in 1615, which concluded that heliocentrism was foolish, absurd, and heretical since it contradicted the Ptolemaic system (as well as the scriptures).
Galileo later defended his views in "Dialogue Concerning the Two Chief World Systems (1632)", which appeared to attack Pope Urban VIII and thus alienated both the Pope and the Jesuits, who had both supported Galileo up until this point. He was tried by the Inquisition, found "vehemently suspect of heresy", and forced to recant. He spent the rest of his life under house arrest. During this time, he wrote "Two New Sciences (1638)", primarily concerning kinematics and the strength of materials, summarizing work he had done around forty years earlier.
Having fathered two illegitimate daughters with his long-time mistress (whom he eventually abandoned), the unconverted Galileo was hardly the example of a devout Catholic. Although Galileo took the girls with him to Florence, he soon found caring for them annoying and decided to send them to an impoverished convent. Because of this “irrepressible egotism” that led him to abandon them, at least one of the girls held an animosity toward him the rest of his life. It was the other daughter who, having become a nun, was chosen to read to Galileo the daily Psalms imposed upon him in his exile as penance by Pope Urban VIII.
Galileo's claims
Galileo claimed to have invented the telescope, but Kepler and his colleagues knew it was available twenty years earlier from one of Galileo’s countrymen, Giovanni Della Porta. Records also show that spectacle-maker Johann Lippershey possessed a license to make telescopes by the mid-1580s. By April 1609 one could buy a telescope from shops in Paris, the same year that Galileo published that he was the first to see the moons of Jupiter, an event in history which is also in doubt since there is evidence that other sighters preceded Galileo, and that his brand of telescope was so small and clumsy it would have been hard to see Jupiter itself, let alone its "moons".
When Kepler pressed him to send the telescope so that his claims could be verified, Galileo gave him the typical ‘the-dog-ate-it’ excuse, claiming that he had “lent it to the Grand Duke for exhibition.” In his usual lack of gratitude, Galileo rarely mentions Kepler’s name in his books, and even those occasions are with the intent to refute him.
The book starts with a tirade against all who tried to rob Galileo “of the glory of his discoveries.”. His self-appointed monopoly on the sky is probably why Galileo also claimed to be the first to discover sunspots, but it was well known that the Jesuits Johannes Farricius and Fr. Scheiner and his assistant Cysat had found the spots earlier, both of whom had published their findings.
Galileo’s deceit reached new heights in his confrontations with the Holy Office of the Catholic Church from 1616-1633. Prior to this, Galileo had made known his views of heliocentrism privately in a 1597 letter to Kepler, yet in a remarkable display of duplicity, in the intervening years between 1597 and up until 1613, he had been teaching against Copernicanism quite vigorously, complete with charts and graphs. A 1606 manuscript of his musings still survives today. Galileo was in a constant whirlwind: saying one thing and doing another, and doing one thing and saying another.
Suffice it to say, after giving him every grace and favor to treat Copernicanism as a hypothesis, not fact, Galileo refused, claiming he had proof when, indeed, he had none at all. The Church hierarchy simply could not put up with his roguery any longer. His former confidant, Cardinal Barberini, later became Urban VIII, and, as pope, made it a point to condemn Galileo for lack of proof.
The most egregious fact about the pre-1641 Galileo is that at the time he was vigorously defending Copernicanism before the Holy Office in 1633, he knew even then the system didn’t work and that he had no substantial proof for it. Since he rejected Kepler’s elliptical orbits (although he used Kepler’s material whenever it was to his advantage, and claimed it as his own), and refused any compromise with the Jesuits who were going over to Brahe’s geocentric model, he was stuck with Copernicus’ forty-eight epicycles, yet he advertised the model as one that bypassed the earlier mechanical problems “with one single motion of the earth.” It is obvious that either Galileo was lying or he never read Copernicus’ book.
Galileo that the Church would not even consider changing its position on the cosmos unless Galileo could provide proof of his claims. In one of his more audacious moves, Galileo tried to prove his case by a strange concoction of theory and conjecture on the nature of tidal action. Having rejected as “occultish” Kepler’s explanation that the combination of the sun’s and moon’s gravity caused the daily tides, Galileo, even knowing that his own explanation could not be physically possible, nevertheless, to save his prestige, tried to convince the Catholic prelates that tides were caused by the tilt of the earth’s axis and the earth’s monthly changes in orbital velocity. In addition, his theory addressed only a 24-hour tidal cycle, but even sailors knew, and reported to the common folk, that the tides alternated every 12 hours. Galileo then tried to explain the discrepancy by postulating that the ocean floor varied in depth.
All things considered, the unconverted Galileo was probably one of history’s better examples of a sophist and propagandist. Although his image is one of an empiricist who made no claims apart from experiment, scientifically speaking the pre-1641 Galileo was a bottom-feeder who often gloried in credit where no credit was due.
Galileo caught in a lie
After attracting the ire of the Catholic Church for stating the Earth orbited the Sun, Italian astronomer Galileo Galilei was put on trial at the Inquisition headquarters in Rome. To avoid being burned at the stake, the 69-year-old was forced to renounce his belief in a heliocentric model of the universe. Nevertheless, the famed polymath still was sentenced to live out his last years under house arrest.
Galileo wrote the "1613 missive" to his friend, the mathematician Benedetto Castelli. The original letter, recently uncovered in a misdated library catalogue at the Royal Society in London, is believed to be the first documented account of his inflammatory arguments for the secular pursuit of science, and it includes his support of Polish astronomer Nicolaus Copernicus’ 1543 theory of a Sun-centered universe.
Salvatore Ricciardo, a science historian at the University of Bergamo in Italy, stumbled upon that original letter in the Royal Society library archives filed under an incorrect date. The original wording of the letter matched the copy seized by the Inquisition, not the one attached to Galileo’s plea. Four centuries after the fact, Galileo has been caught in a lie.
The amendments to the document weren’t severe; they mostly expressed Galileo’s beef with the Church and watered down the vehemence of his claims. For instance, Galileo originally called out certain Biblical passages as “false if one goes by the literal meaning of the words”, but in his later amendments, he crossed out the word “false” and scrawled in, “look different from the truth.”
Even in its original form, the letter was by no means Galileo’s only offense to the Catholic Church. In 1632, after the Church had pulled Copernicus’ writings out of circulation and outlawed publications supporting the heliocentric theory, Galileo published a book laying out scientific support for the Copernican model.
That proved to be the final nail in Galileo’s coffin. Once again, Galileo attempted to manage the story. As the Inquisition descended upon him, he claimed he was writing “hypothetically”, but the Church didn’t buy it this time either, and in 1633 he was put on trial.
Quotes
Measure what is measurable, and make measurable what is not so.
It is necessary for the Bible, in order to be accommodated to the understanding of every man, to speak many things which appear to differ from the absolute truth so far as the bare meaning of the words is concerned.
I have been judged vehemently suspect of heresy, that is, of having held and believed that the sun in the centre of the universe and immoveable, and that the earth is not at the center of same, and that it does move. Wishing however, to remove from the minds of your Eminences and all faithful Christians this vehement suspicion reasonably conceived against me, I abjure with a sincere heart and unfeigned faith, I curse and detest the said errors and heresies, and generally all and every error, heresy, and sect contrary to the "Holy" Catholic Church.
Science proceeds more by what it has learned to ignore than what it takes into account.
I think that in the discussion of natural problems we ought to begin not with the Scriptures, but with experiments, and demonstrations.
Mathematics is the key and door to the sciences.
Philosophy itself cannot but benefit from our disputes, for if our conceptions prove true, new achievements will be made; if false, their refutation will further confirm the original doctrines.
The doctrine that the earth is neither the center of the universe nor immovable, but moves even with a daily rotation, is absurd, and both philosophically and theologically false, and at the least an error of faith.
Among the great men who have philosophized about [the action of the tides], the one who surprised me most is Kepler. He was a person of independent genius, [but he] became interested in the action of the moon on the water, and in other occult phenomena, and similar childishness.
What has philosophy got to do with measuring anything? It's the mathematicians you have to trust, and they measure the skies like we measure a field.