Excerpts from Galileo's Daughter by Dava Sobel
(a biography of Galileo enhanced by letters
that were written to him by his Daughter).

(Added to this website on 1/12/10.)

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In chapter two of Book One of the series Behind Light's Illusion is a short biographical sketch of Galileo.   In chapter one of Book Five of the series Behind Light's Illusion are some sentences pertaining to Galileo.

During... the Copernican Revolution, Brahe, Kepler, and Galileo did much to improve upon Copernicus' work.   ...supposed heretics continued to be persecuted by the Inquisition, and some... were tortured and burned at the stake.   However, it was not until Galileo offered enough proof to make Copernicus' theory more than just a mathematical exercise that the Catholic Church became fearful enough to take take more lasting steps.

In very ancient times, astrology was the science encompassing many forms of mathematics, planetary motion, planetary influences, and their consequences.   Astronomy branched off of this old science and began to be what is considered legitimate today.   Until the time of Galileo, astrology was part of theology, medicine, and related sciences.   When astrology in the form of Copernicus' theory, as championed by Galileo, threatened to undermine the infallibility of the pope, Galileo was forced to recant and was placed upon house arrest for the remainder of his life.   The science of astrology was denounced along with the the branch we now call astronomy.

Upon reading Galileo's Daughter it was apparent that the short biographical sketch and the statements above on Galileo should be expanded and clarified to avoid adding to the misconceptions that are prevalent regarding Galileo, the Catholic Church, and the Inquisition.   Galileo was tried for writing his book, Dialogue, which showed the superior nature of Copernican theory (that the earth moved around the sun), and was written in Italian for the educated layman rather than Latin which only the scholars (who usually had their reputations to consider) could read.   At the time of Galileo's trial, he had been in ill health and was even more stressed physically and mentally from the machinations of the Inquisition.   The following is taken from Dava Sobel's excellent book (the best biography of Galileo that I have read).

"In framing Galileo's trial as a simplistic case of science versus religion, anti-Catholic critics have claimed that the Church opposed scientific theory on biblical grounds, and that the outcome mocked the infallibility of the pope.   Technically, however, the anti-Copernican Edict of 1616 was issued by the Congregation of the Index, not by the Church.   Similarly, in 1633, Galileo was tried and sentenced by the Holy Office of the Inquisition, not by the Church.   And even though Pope Paul V approved the Edict of 1616, just as Pope Urban VIII condoned Galileo's conviction, neither pontiff invoked papal infallibility in either situation.   The freedom from error that belongs to the pope as his special privilege applies only when he speaks on matters of faith and morals.   What's more, the right of infallibility was never formally defined in Galileo's time, but issued two centuries later from Vatican Council I, held in 1869-70.

"Although Urban personally believed in his own power enough to boast that the sentence of one living pope - namely Urban himself - outweighed all the decrees of one hundred dead ones, he refrained from claiming infallibility in the Galileo case.

"French philosopher Rene Descartes, who followed Galileo's trial from his home in Holland, understood these distinctions.   Thus Descartes could comment hopefully to a colleague: As I do not see that this censure has been confirmed either by a Council or by the Pope, but proceeds solely from a committee of cardinals, it may still happen to the Copernican theory as it did to that of the antipodes [the eighteenth-century censured notion of a sub-Earth with human inhabitants] which was once condemned in same way.   Nevertheless Descartes, a product of his Jesuit education and a devout Catholic throughout his life, withheld from publication the book he himself had just completed, Le Monde, which espoused Copernicus' view of the universe.

"Numerous churchmen, however - including highly placed clerics such as Ascanio Piccolomini, the Archbishop of Siena - had endorsed Galileo's Dialogue from their initial reading of it and continued to consider the author their friend.   It seems exceeding strange to me, Archbishop Piccolomini had written to Galileo when the outcry over Dialogue first arose, that such a recent and precise approbation should be opposed by the passions of some people who might find fault only in what they conceive of the book, for the work itself ought to appease the most timid conscience.   On the other hand, I would say you deserve this and worse, for you have been disarming by steps those who have control of the sciences, and they have nothing left but to run back to holy ground."

Galileo is most famous for creating and effectively using his own telescope after the telescope had been invented in the Netherlands, and for his book regarding Copernican theory.   However, most physicists believe that his other work has done more for science.   For instance, he did numerous experiments and showed that mathematics could and should be applied to science - a great step leading to modern scientific method.   He showed the math behind the acceleration of falling bodies which Newton later used as a foundation.   He showed that volume increases as a cube while strength (area) increases as a square - which leads to the reason that insects with exoskeletons cannot exceed a certain size, why elephants can fall six feet and break the legs while a mouse can fall a thousand feet and not be injured, and why manmade structures must be reinforced more when they are large.   He showed that a small weight of heavy liquid can cause a heavier object to float upon it - and he showed why this is so (developing the theories of Archimedes).   He discovered the mathematics of the pendulum and invented the pendulum clock.     He showed that the moon always had only one side facing Earth and that we can see only edgewise glimpses of parts of the other side, discovered the phases of Venus, found that the Milky Way is composed of individual stars, and discovered four of the moons of Jupiter.   He developed the math and path of artillery projectiles.   He composed music.   He invented a proportional compass and an early version of a thermometer.   Galileo is often considered the real father of relativity, the understanding that there is no absolute motion, that velocity is relative.

Regardless of the technicalities, Urban's treatment of Galileo was despicable to say the least, and from his actions in other matters as well, it seems apparent that Urban had excessive ego and was something of a psychopath.   It was Urban who listened to Galileo's enemies, would not allow any of Galileo's work to be further published or distributed, kept Galileo under house arrest until his death, would not allow Galileo to see his daughter until only shortly before her death, and would later not allow Galileo to speak to anyone capable of understanding his work.   When Galileo's book was banned, copies of it began to sell on the black market at six times their usual worth - and those who had no copy of it tried to borrow a copy to read.   Galileo died at age 75, still concerned about the fate of his other work - which was more important than the invention of the telescope and Copernican theory.   As time passed, Galileo was given his due, and his elaborate tomb today is a tourist attraction.   Urban, who was hated by many, died in 1644, over two years after Galileo.   The people of Rome showed how they felt about Urban by demolishing a statue of him in the courtyard of the Collegio Romano.

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