Category Archives: Myths of Science

Galileo, Foscarini, The Catholic Church, and heliocentricity in 1615 Part 2 –the consequences: A Rough Guide.

In part one I outlined the clash, which took place between Galileo and Foscarini on the one side and the Catholic Church on the other in the second decade of the seventeenth-century. I ended by saying that this initial confrontation had very few consequences for Galileo at the time, who continued to be the highly feted darling of the North Italian in-crowd, including the higher echelons of the Catholic Church. Of course the events of 1615/16 would come back to haunt Galileo when he was tried for writing and publishing his Dialogo in the 1630s but that is a very complex topic that require a post of its own sometime in the future. I also wrote that the books of Foscarini and of the Protestant Copernicans, Michael Maestlin and Johannes Kepler were placed on the Index of Forbidden Books. Interestingly De revolutionibus was only placed on the Index until corrected. It is here that we will pick up the thread and examine the consequences of the Church’s actions on the development of astronomy in the seventeenth-century.

What did it mean when I say that De revolutionibus was only placed on the Index until corrected? This means that De revolutionibus was not forbidden but that only those statements within the book, which claimed that heliocentricity was a proven fact, were to be removed. This mild censorship, only a handful of passages in the whole book were affected, was carried out comparatively quickly and the thus censored version was given free to be used by astronomers already in 1621. The whole of this episode demonstrates that the powers that be within the Church were well aware that De revolutionibus was an important astronomical text and should, despite the judgement of the eleven members of the commission set up to adjudicate on the affair that the idea that the Sun is stationary is “foolish and absurd in philosophy, and formally heretical since it explicitly contradicts in many places the sense of Holy Scripture…”; while the Earth’s movement “receives the same judgement in philosophy and … in regard to theological truth it is at least erroneous in faith”, remain available to Catholic astronomers for their studies.

There is a widespread popular perception that the Church’s theological rejection of the theory of heliocentricity led to a breakdown of astronomical research in Catholic countries in the seventeenth-century. Nothing could be further from the truth. As mentioned in the first part of this post, some historians think that Cardinal Bellarmino’s admission in his letter to Foscarini that … if there were a real proof that the Sun is in the centre of the universe, that the Earth is in the third sphere, and that the Sun does not go round the Earth but the Earth round the Sun, then we should have to proceed with great circumspection in explaining passages of Scripture which appear to teach the contrary …, was interpreted by many Jesuit and Jesuit educated astronomers as a challenge to find an empirical proof for heliocentricity. As we shall see there is quite a lot of circumstantial evidence to support this claim.

An important historical fact to be born in mind when considering the development of astronomy in the seventeenth-century was that there existed no empirical proof for the heliocentric hypothesis, whether it be in the original form proposed by Copernicus or the much more sophisticated form developed by Kepler. The astronomers would have to wait until 1725 before James Bradley delivered the first proof of the earth’s annual orbit around the sun with his discovery of stellar aberration and slightly longer before the geodesists demonstrated that the earth is an oblate spheroid thus confirming a prediction made by both Newton and Huygens that diurnal rotation would result in the earth having this form thus proving indirectly the existence of diurnal rotation. This tends to be forgotten or simply ignored by those claiming that the Church should have accepted heliocentricity as a fact in 1615. In reality the heliocentricity became accepted by almost all astronomers whether Catholic or non-Catholic by around 1660, long before any empirical proof existed, on the basis of accumulated circumstantial evidence and the lack of a convincing alternative. A lot of that circumstantial evidence was delivered by Catholic astronomers, who despites the Catholic theological position, continued to work avidly on the development of the modern astronomy.

It is also important to realise that although the Church banned claiming that heliocentricity was a fact, the heliocentric theory, it was still perfectly possible to speculate about heliocentricity, the heliocentric hypothesis. Throughout the seventeenth-century Catholic astronomers in Italy adopted an interesting strategy to deal with the Church’s ban of the heliocentric theory. They would preface their works with a statement of the fact that in its wisdom the Church had shown the heliocentric theory to be contrary to Holy Scripture and thus factually false and then proceed to discuss this interesting mathematical hypothesis without claiming it to be true. This strategy sufficed for the Inquisition’s guardians of the truth and thus the astronomers continued to discuss and disseminate heliocentricity with impunity.

Scientific theories are not only disseminated by their supporters but often also by their opponents. Long before Galileo muddy the waters with his heated challenge to the Church’s exclusive right to interpret the Bible it is certain that more people learnt of the existence of the heliocentric hypothesis and its basic details from the works of Christoph Clavius, a convinced defender of geocentricity, than from De revolutionibus. In his commentary on the Sphere of Sacrobosco, an introductory astronomy textbook, Clavius discussed Copernicus’ heliocentric hypothesis sympathetically, respecting its mathematical sophistication, whilst firmly rejecting it. This book went through numerous editions and was the most widely disseminated and read, by both Catholic and Protestant students, astronomy textbook throughout most of the seventeenth-century and was for many their first introduction to the ideas of Copernicus. It was also Clavius’ postgraduate students, in his institute for mathematical research at the Collegio Romano, who provided the very necessary empirical confirmation of Galileo’s telescopic discoveries in 1611, shortly before Clavius’ death. This activity by Jesuit astronomers pushing the boundaries of astronomical knowledge did not cease following the decisions of 1616.

There was a slowdown in the development of modern astronomy in the second and third decades of the seventeenth-century that has nothing to do with the Church’s ban but was the result of a lack of technological advance. In the four years between 1609 and 1613 European astronomers had discovered everything that it was possible to discover using a Dutch or Galilean telescope with a convex objective and a concave eyepiece. The only new discoveries were the observations of a transit of Mercury by Gassendi in 1631 and a transit of Venus by Horrocks in 1639 neither of which had an immediate impact because they didn’t become widely known until much later. For various reasons, not least Galileo’s very public rejection of it as inferior, the superior Keplerian or astronomical telescope, with two convex lenses, didn’t start to become established until the 1640s. However once established the new discoveries began to flow again: the moons of Saturn, the rings of Saturn, diurnal rotation of the planets. Many of these new discoveries, which added new circumstantial evidence for heliocentricity, were made by Giovanni Domenico (Jean-Dominique) Cassini (1625–1712) a Jesuit educated Catholic astronomer. It was also Cassini, with the support of his teachers the Jesuits Giovanni Battista Riccioli and Francesco Maria Grimaldi, who proved, using the heliometer constructed for this purpose in the San Petronio church in Bologna, that either the sun’s orbit around the earth or the earth’s orbit around the sun must be an ellipse, as required by Kepler. Although this proved that the orbit is an ellipse it didn’t show which system was correct.

Cassini, who would go on to become the leading observational astronomer in Europe, always avoided committing himself to any systems simply delivering empirical results and leaving the cosmological interpretation to others. Although confirming Cassini’s heliometer results Riccioli stayed committed to semi-Tychonic system, in which the inner planets orbited the Sun, which in turn together with Saturn and Jupiter orbited the Earth. Riccioli presented this rather bizarre mongrel in his Almagestum Novum published in 1651. Riccioli’s Almagestum contained descriptions of all the various possible systems, including the Copernican, and became a very widely disseminated and read technical textbook for astronomers, both Catholic and Protestant. Like Clavius before him, Riccioli introduced many to heliocentricity for the first time. The Almagestum contained 126 arguments concerning the Earth’s motion 49 pro and 77 contra the most extensive discussion of the problem ever. You can read Chris Graney’s English translation of the arguments here. Although Riccioli came out against heliocentricity his analysis was sympathetic enough to the concept that he was actually investigated by the Inquisition.

Having been made available by the Index copies of De revolutionibus appear only to have been actually censored within Italy nearly all the surviving censored copies, including Galileo’s, coming from there. Outside of Italy, with the notable exception of Descartes, nobody seems to have taken very much notice of the Inquisition’s ban. Descartes appears to have withheld publication of his The World, in the 1630s, containing his defence of heliocentricity, out of respect for his Jesuit teachers. Publishing his views, in modified form, first in his Principles of Philosophy in 1644.

Another Frenchman, Pierre Gassendi like Descartes educated by the Jesuits, who became professor of mathematics at the Collège Royal in Paris in 1645 published his views on astronomy in his Institutio astronomica, although formally a supporter of the Tychonic system, Gassendi’s presentation of the Copernican system is so sympathetic that many historians have interpreted him as a secret supporter of heliocentricity. Gassendi also published biographies of Tycho, Peuerbach, Regiomontanus and Copernicus. Like Riccioli, Gassendi’s astronomical writings were very popular and very widely read, again leading to a widespread dissemination of the principles of heliocentricity.

Another leading French Catholic astronomer, Ismael Boulliau was an open and avid supporter of the Keplerian elliptical astronomy and was indeed the first to hypothesise that gravity ought to be an inverse quadrate force, a significant step in the road to acceptance of heliocentricity. It was Boulliau’s dispute with the English astronomer Seth Ward about Kepler’s second law, which nobody liked, both parties offering alternatives, that first made Newton aware of Kepler’s system.

By about 1660 enough circumstantial evidence had been accumulated that most astronomers in Europe both Catholic and Protestant, with the necessary education to do so, had accepted heliocentricity as a fact with a small minority still holding out for a Tychonic system. In the end the Tychonic system had fallen victim of Ockham’s razor being viewed as overly complex in comparison with the Keplerian elliptical system for which more and more evidence had accumulated throughout the preceding fifty years. A significant advance in the development of modern physics in which Galileo’s Discorsi had played an important role also contributed crucially to this acceptance, dealing as it did with the physical problems of terrestrial motion. A detailed analysis of these developments would make this already over long post even longer and must be dealt with separately.

Although by no means an exhaustive presentation of the development of astronomy in the seventeenth-century, I think the above contains enough to demonstrate that the Church’s ban of the heliocentric theory had very little negative influence on that development and that Catholic astronomers played a leading role within it. Returning to my earlier speculation, I feel justified in saying that had Galileo and Foscarini not forced the Church’s theologians into a corner in 1615, then the Catholic astronomers, and in particular the Jesuits and their pupils, would have led the Church to an acceptance of heliocentricity within the seventeenth-century.

 

 

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Filed under History of Astronomy, History of science, Myths of Science

How much can you get wrong in an eight hundred word biographical sketch of a very famous sixteenth and seventeenth-century mathematicus and philosophicus? – One helluva lot it seems?

If someone is doing the Internet equivalent of being a big-mouthed braggart and posting an article with the screaming title, “10 Absurdly Famous People You Probably Don’t Know Enough About” you would expect them to at least get their historical facts right, wouldn’t you? Well you would be wrong at least as far as “absurdly famous” person number seven is concerned, Galileo Galilei. Tim Urban the author of this provocative article on the ‘Wait But Why’ blog appears to think that history of science is something that you make up as you go along based on personal prejudice mixed up with some myths you picked up some night whilst drunk in a bar. Having not had a real go at somebody else’s terrible history of science for sometime now and not having deflated my favourite punching bag, Galileo or rather the hagiographic imbeciles who write about him, for even longer I thought I would kill two birds with one stone and correct Mr Urban’s little piece as it were a high school term paper. The blue text is original Urban the black comments are mine.

Galileo-300x263

Lived: 1564 – 1642

He makes a promising start in that he at least got the years of birth and death right, although with the same amount of effort he could have given us the exact dates – 15 February 1564 – 8 January 1642

In 11 words: Rare giant of scientific advancement fighting against hopelessly-backward Catholic Church

After that reasonably good beginning we go rapidly down hill. As I have commented on a number of occasions Galileo was by no means as rare or as gigantic as he is usually painted. He also spent most of his life getting along very happily with the Catholic Church with whom he was on good terms and which was in a lot of things, including scientific one, anything but hopelessly-backward. Just to quote one example about which I’ve blogged in the past, it was the Jesuit astronomers at the Collegio Romano who delivered the very necessary scientific confirmations of Galileo’s telescopic astronomical discoveries and then invited Galileo to Rome to celebrate them.

His main thing: Einstein called Galileo “the father of modern science,” which sums things up pretty nicely.

Einstein, as a leading historian of Renaissance science is of course highly qualified to make such a judgement. Regular readers of this blog should by now know my opinion of such expressions as “the father of” and in particular their use to describe Galileo. For those that don’t I recommend my post, “Extracting the stopper”, as a good starting-point.

Galileo made major discoveries about the motion of planets and stars, the motion of uniformly accelerated objects (i.e. that two objects would fall at the same rate regardless of their masses), sound frequency, and the basic principle of relativity, among other things

I must admit to being somewhat perplexed by the claim that Galileo made “major discoveries about the motion of planets and stars”; I’m not aware of any achievements by the good man in this direction, perhaps somebody could enlighten me?

—and major advancements in technology, including inventing or improving upon the telescope, microscope, thermometer, pendulum, and the compass.

Galileo made an improved telescope and might have been one inventor of the microscope, although this is clouded in uncertainty. He experimented with a thermoscope, not a thermometer, but probably did not invent it. He neither invented nor improved the pendulum and I don’t think he or anybody else ever claimed that he did so. He did however investigate the properties of the pendulum, although the law he set out for the pendulum is actually wrong.

The last claim is quite funny and turns up time and time again quoted by people who literally don’t know what they are talking about. Galileo had nothing to do with the (magnetic) compass but manufactured and marketed an improved version of the sector, or proportional or military compass. This is a hinged ruler with numerous scales used for making mathematical calculations particularly by artillery officers. This instrument has several independent inventors; the one improved by Galileo was invented by his mentor, Guidobaldo del Monte.

Galileo's military compass

Galileo’s military compass

His work was central to most future developments in science, including those of Newton and Einstein, and most of what he discovered was in contradiction with conventional wisdom—his work was as shocking and revolutionary in the 1600s as Einstein proclaiming that “time is relative” was in the 1900s.

This is typical of the hagiographical hogwash dished up by people writing about Galileo. The only part of Galileo’s work ‘central’ to Newton was the parabolic flight path of projectiles, which was discovered independently by other including Thomas Harriot. His only connection to Einstein is the rejection of Galilean relativity in the theory of the latter. Very little of Galileo’s own work was shocking and the only parts that were in anyway revolutionary were the laws of fall, discovered independently and earlier by Benedetti, and heliocentricity, a field in which Galileo was not the discoverer or inventor but merely the polemicist, who probably did more damage than good through his advocacy.

But the most impressive part about Galileo, other than his ability to make such a cranky facial expression in the above painting, is that he did everything he did in the face of threats and repression by the Catholic Church and their inane loathing of ground breaking scientific advancements.

I begin to get the impression that our author has a personal problem with the Catholic Church, which did not have an “inane loathing of ground breaking scientific advancements”, and except in the one case Galileo did nothing in “the face of threats and repression by the Catholic Church” but actually received much support and encouragement from many leading figure in the Church hierarchy for the vast majority of his life and work.

The main thing the Church kept yelling at Galileo for was his backing and advancement of Copernicus’s heliocentric model of the universe, which puts the sun, instead of the Earth, in the center of the solar system and suggests that the Earth’s spinning is why the sun appears to revolve around the Earth. The Church declared heliocentrism to be “foolish and absurd in philosophy, and formally heretical since it explicitly contradicts in many places the sense of Holy Scripture”—in particular, the parts of scripture that said things like, “the world is firmly established, it cannot be moved” and “the Lord set the earth on its foundations; it can never be moved”—and ordered Galileo “to abstain completely from teaching or defending this doctrine and opinion or from discussing it… to abandon completely… the opinion that the sun stands still at the center of the world and the earth moves, and henceforth not to hold, teach, or defend it in any way whatever, either orally or in writing. “That would be like modern-day governments imprisoning geologists who studied ancient rocks because their findings conflicted with the Bible’s accounts of the Great Flood. Or like preventing gay people from getting married because of passages in the Bible about sexual orientation. Thankfully, those times are over.

The above paragraph contains the real reason that Mr Urban is frothing at the mouth about the Catholic Church, Galileo’s clash with the Church on heliocentricity. Once again I’m not going to go into great detail about the whole sad sorry affair but will for the umpteenth time repeat that the central problem had very little to do with science, astronomy, cosmology or whatever but with the fact that in 1615 Galileo tried to tell the Church how to interpret the Bible. If he had not done this and instead bided his time patiently, as suggested by his friends, including Cardinal Maffeo Barberini the later Pope Urban VIII, the Church would in its own time almost certainly have adopted heliocentricity. Instead of which through Galileo’s pig-headedness the acceptance of heliocentricity by the Catholic Church was delayed by about one hundred and fifty years.

So the Church repressed the greatest genius of the century,

There’s no such thing as the greatest!

… finding him “vehemently suspect of heresy,” and placed him under house arrest for the rest of his life. Luckily, Galileo just hung out on his couch and kept doing his thing, publishing some of his most important works while under house arrest.

I know Galileo fans and militant atheists don’t like to hear this but, for the ‘crime’ of which he was found guilty, Galileo was treated very, very gently and his sentence was very mild.

Other things:

  • Galileo never married, having all three of his children out of wedlock with the same woman.
  • We got something right!
  • One of the reasons Galileo started inventing things (like the telescope) in the first place was that he badly needed money to deal with all the money his starving artist little brother kept “borrowing” from him.
  • Like many Renaissance mathematicians Galileo supplemented his income by designing, manufacturing and selling scientific instruments. He didn’t invent the telescope! Galileo was notoriously always short of money not because he supported his little brother financially, which he did, but because he enjoyed the good life and tended to live beyond his means.
  • He was briefly a professor at the University of Pisa, but he was inappropriate with his students and the university didn’t renew his contract.
  • The second part of the above sentence is a pure fabrication. Galileo was professor of mathematics in Pisa from 1589 till 1592 when he applied for and received the more prestigious and better-paid professorship for mathematics in Padua where he remained until 1610.
  • Despite his conflicts with the Church, Galileo was a devout Catholic. He briefly became a priest before his father convinced him to go into medicine, and his two daughters were nuns. But he was critical of the Church’s repression of science, stating, “Holy Writ was intended to teach men how to go to Heaven, not how the heavens go.”
  • That Galileo was a devout Catholic is a standard claim in the history of science repeated, I think, to make the Church look worse for their persecution of the man. This claim has been strongly challenged by Renaissance historian; David Wootton in his biography “Galileo: Watcher of the Skies” (Yale University Press, 2010), which paints Galileo convincingly as a very lax Catholic and possibly an unbeliever. Galileo was never a priest but did spend a few months in a monastery as a teenage novice, although he never took holy orders. Galileo’s two daughters were placed in a monastery because, being illegitimate, he considered them unmarriageable and also to spare him the cost of their dowries, a standard procedure in that period.
  • One of Galileo’s worst offenses against the Church was creating a character called Simplico in his famous book Dialogue Concerning the Two Chief World Systems, who always presented the old, incorrect, geocentric view. Simplico suggests “simpleton” in Italian just like it does in English, and in the book, Simplico does not come off very well. The issue is that a lot of what Simplico says in the book were well known to be the direct views of the Pope (Urban VIII), indirectly insulting the Pope and hastening Galileo’s path toward house arrest.
  • The character in the Dialogo who presents the case for geocentricity is called Simplicio not Simplico. The insult of the Pope was much more direct than suggested here. When Urban VIII granted Galileo permission to write a book explaining both geocentricity and heliocentricity, in order to prove that Catholics were not ignorant of the latter theory, he specifically instructed Galileo to include his own theological argument against deciding for one system over the other because this would “limit and restrict the Devine power and wisdom to some particular fancy of my own”. A not unreasonable viewpoint given that there were no proofs for the heliocentric system at that time. Galileo did as instructed including exactly those words in the final speech of Simplicio, the simpleton, on the last page of the book, who had had seven kinds of intellectual shit kicked out of him in the preceding four hundred pages (in the edition I own) by the other two characters. This really reduced Urban’s argument to a joke! Not a smart move, Signore Galilei.
  • It wasn’t until 200 years later in 1835 that the Church finally stopped its prohibition of books advocating heliocentrism and not until 1992 that the Vatican officially cleared Galileo’s name of any wrongdoing.
  • The church allowed the publication of an edition of Galileo’s works, excluding the Dialogo, in 1718 just 76 years after his death. In 1741 a complete edition of his works was authorised by Pope Benedict XIV. The general ban on works advocating heliocentricity was lifted in 1758.
  • It should be noted that Galileo’s church difficulties occurred in the heart of the Renaissance. You can only imagine what it was like to be a scientist in the far more repressive Middle Ages (and how much potential scientific advancement was stifled).
  • We’re back in anti-Church bullshit city! Within the history of science Galileo’s difficulties with the Church, which he largely brought down on his own head, remain a largely isolated incident. The Middle Ages were by no means more repressive than the Renaissance and in fact much scientific progress was made during the Middle Ages, following the re-establishment of an urban culture around 1000 CE. Also it should be noted that the majority of that progress was made by members of the Catholic Church. Galileo was very much aware of the work of his medieval predecessors and built his own work on the foundations that they had constructed.
  • Some weirdo cut the middle finger off of Galileo’s corpse a century after his death, and it is currently on display at the Museo Galileo in Florence.
  • He got something right again!
  • Galileo’s dad begrudgingly allowed him to leave medicine in favor of mathematics and died a few years later when Galileo was an amateur math professor—he had no idea his son was anything special, let alone “the Father of Modern Science.”
  • It is true that Vincenzo Galilei was not particularly enthusiastic when his son abandoned his medical studies, however Galileo was never an “amateur math professor” but a fully paid professional. On the “Father of Modern Science”, see above.

2014 equivalent: Elon Musk

I find the concept of Elon Musk being the 2014 equivalent of Galileo Galilei quite simply mindboggling!

Mr Urban your term paper does not meet the required standards. Your research is to put it mildly very sloppy and personal prejudice is not a substitute for scholarly endeavour, therefore I cannot award you anything but an F!

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Filed under History of Astronomy, History of science, Myths of Science, Renaissance Science

Published on…

Today I have been mildly irritated by numerous tweets announcing the 5th July 1687, as the day on which Isaac Newton’s Principia was published, why? Partially because the claim is not strictly true and partially because it evokes a false set of images generated by the expression, published on, in the current age.

In the last couple of decades we have become used to images of hoards of teens dressed in fantasy costumes as witches queuing up in front of large bookstores before midnight to participate in the launch of the latest volume of a series of children’s books on a juvenile wizard and his adventures. These dates were the days on which the respective volumes were published and although the works of other authors do not enjoy quite the same level of turbulence, they do also have an official publication date, usually celebrated in some suitable way by author and publisher. Historically this has not always been the case.

In earlier times books, particularly ones of a scientific nature, tended to dribble out into public awareness over a vague period of time rather than to be published on a specific date. There were no organised launches, no publisher’s parties populated by the glitterati of the age and no official publication date. Such books were indeed published in the sense of being made available to the reading public but the process was much more of a slapdash affair than that which the term evokes today.

One reason for this drawn out process of release was the fact that in the early centuries of the printed book they were often not bound for sale by the publisher. Expensive works of science were sold as an unbound pile of printed sheets, allowing the purchaser to have his copy bound to match the other volumes in his library. This meant that there were not palettes of finished bound copies that could be shipped off to the booksellers. Rather a potential purchaser would order the book and its bindings and wait for it to be finished for delivery.

Naturally historians of science love to be able to nail the appearance of some game changing historical masterpiece to a specific date, however this is not always possible. In the case of Copernicus’ De revolutionibus, for example, we are fairly certain of the month in 1543 that Petreius started shipping finished copies of the work but there is no specific date of publication. With other equally famous works, such as Galileo’s Sidereus Nuncius, the historian uses the date of signing of the dedication as a substitute date of publication.

So what is with Newton’s Principia does it have an official date of publication and if not why are so many people announcing today to be the anniversary of its publication. Principia was originally printed written in manuscript in three separate volumes and Edmond Halley, who acted both as editor and publisher, had to struggle with the cantankerous author to get those volumes out of his rooms in Cambridge and into the printing shop. In fact due to the interference of Robert Hooke, demanding credit for the discovery of the law of gravity, Newton contemplated not delivering the third volume at all. Due to Halley’s skilful diplomacy this crisis was mastered and the final volume was delivered up by the author and put into print. July 5th 1687 is not the date of publication as it is understood today, but the date of a letter that Halley sent to Newton announcing that the task of putting his immortal masterpiece onto the printed page had finally been completed and that he was sending him twenty copies for his own disposition. I reproduce the text of Halley’s letter below.

 

Honoured Sr

I have at length brought you Book to an end, and hope it will please you. the last errata came just in time to be inserted. I will present from you the books you desire to the R. Society, Mr Boyle, Mr Pagit, Mr Flamsteed and if there be any elce in town that you design to gratifie that way; and I have sent you to bestow on your friends in the University 20 Copies, which I entreat you to accept.[1]

 

 

[1] Richard S. Westfall, Never at Rest: A Biography of Isaac Newton, Cambridge University Press, Cambridge etc., 1980, p. 468.

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The Transition to Heliocentricity: The Rough Guides

Prompted by a question from Brian Cox, on Twitter, I wrote a post outlining the history of Galileo’s engagement with heliocentricity and the Catholic Church giving it the sub-title “A Rough Guide”. This post in turn provoked a series of question and answers on Twitter between myself and my #histsci soul-sister Dr Rebekah “Becky” Higgitt, which I developed into a post on the role played by the observations of the phases of Venus in the gradual acceptance of heliocentricity; a second post to which I added the sub-title “A Rough Guide”. I have now decided to go with the flow and produce a series of posts dealing one by one with the various things that contributed to the gradual transition from a geocentric to a heliocentric astronomy during the sixteenth and seventeenth centuries, each post bearing the sub-title “A Rough Guide”.

The aim is to demonstrate that this transition was not a simple question of the one is right and the other wrong, as it is unfortunately all too often presented today, particularly by those of a gnu atheist persuasion, but that within the context of the times the various factors involved often required subtle and careful interpretation and were not the clear cut evidence that hindsight seems to make them now. For example, I hope I have already achieved this in the post on the phases of Venus. To make it easier for readers to put the whole series together and to form, for themselves, the big picture, I have added a new separate page to the Renaissance Mathematicus, which will contain a list of all the posts, with links.

Suggestions, from readers, for topics to be dealt with in this series are welcome; I already have a list of eight, the first of which will be posted some time next week.

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The Phases of Venus and Heliocentricity: A Rough Guide

The word planet comes from the Greek word for wanderer. When people first started observing the heavens most of those points of light that we call stars appeared to remain fixed in place relative to each other, although the whole bowl of twinkling points appeared to revolve around the earth once every twenty-four hours, hence they became known as the sphere of fixed stars. With time however the early observers noticed that some of those points of lights behaved very differently to the vast majority, appearing to wander somewhat randomly around the heavens and these maverick stars became the planets. Further observations showed that the movement of the wanderers were in fact not random but followed a regularity that could, over suitably long periods of time, be recorded and then predicted in advance and planetary astronomy was born, however the behaviour of the various wanderers differed.

The Sun and Moon, which were both regarded as planets, have very special geocentric orbits and delivered the basics of timekeeping, the year and the day – the Sun – and the month and possible the seven day week (the phases of the moon) – the Moon. In the most common order of the planets, Moon, Mercury, Venus, Sun, Mars Jupiter and Saturn moving outwards from the Earth the remaining five planets were divided into the inner and outer planets with the Sun’s orbit providing the dividing line. The outer planets – Mars, Jupiter and Saturn – display a rather curious behaviour. They trundle along quite regularly in one directions then halt, reverse direction for a short period, halt again then reversing direction once again continue as before. This brief period of reversed motion is called retrograde motion and I’ll deal with its history and significance for heliocentricity in another post.

The two inner planets – Mercury and Venus – display a completely different orbital behaviour viewed from the Earth. Firstly they never stray very far from the Sun. They disappear for periods of time first being one side of the sun then reappearing on the other side and lastly their orbits around the Earth is exactly the same as the Sun’s i.e. one year. This combination of phenomena led some astronomers in antiquity to hypothesise that Venus and Mercury do not orbit the Earth but the Sun, being carried with it on its annual journey around the Earth. This model became know as the Egyptian or Heracleidian system. It was also presented in late antiquity by Martianus Capella in his De nuptiis Philologiae et Mercurii (“On the Marriage of Philology and Mercury”) a text that was very well known and popular in the Middle Ages and so the Heracleidian model was also well known in the Early Modern Period.

 

Capellan system - Valentin Naboth (1573)

Capellan system – Valentin Naboth (1573)

In the sixteenth-century the Danish astronomer Tycho Brahe seeing the advantages of Copernicus’ heliocentric astronomy but very unhappy about a moving Earth extended the Heracleidian system in that he let all five of the planets orbit the Sun, which in turn orbited the Earth.

 

Tychonic System

Tychonic System

The telescope made its public debut in Holland in September 1608. Within a year Thomas Harriot in London, Simon Marius in Ansbach, Galileo Galilei in Padua, and the Jesuits Odo van Maelcote and Giovanni Paolo Lembo in Rome were all using the new instrument to make astronomical observations and ushering in a new era in our understanding of the cosmos. Famously, Galileo was the first in print with his Sidereus Nuncius, the impact of which I’ve dealt with here. The earliest known reference to the possibility of Venus having phases occurs in a letter sent by the mathematician Benedetto Castelli to his old teacher Galileo in December 1610. Referencing thoughts of Copernicus from chapter ten of book I of De revolutionibus, Castelli enquired if the telescope would make it possible to observe phases of Venus. This enquiry makes two assumptions, firstly that Venus orbits the sun and secondly that it is lit by reflected light from the sun and is not a light source itself.

Galileo experts are divided as to whether Galileo had already been considering the question before he received Castelli’s letter or whether he appropriated the idea without giving his onetime student the credit he deserved. Whatever, shortly after receiving this letter Galileo wrote to Kepler in Prague enclosing the following anagram announcing a new sensational discovery:

Haec immatura a me iam frustra leguntur o.y.

This reads in translation, “I am now bringing these unripe things together in vain, Oy!” It was common practice for researchers in the Early Modern Period to announce their new discoveries in the form of anagrams to establish their priority in an age that knew no patents or copyright in the modern sense. Kepler was unable to decipher Galileo’s message and had to wait until the Tuscan astronomer revealed his sensation to the world. Deciphered the anagram read as follows, in Latin:

Cynthiae figuras aemulatur mater amorum

In English translation this reads as, “The mother of love [Venus] copies the forms of Cynthia [the Moon]”. In other words Galileo had discovered that Venus has phases like the Moon and therefore must orbit the Sun and not the Earth. Also in 1610 Galileo informed his friend and former patron Christoph Clavius in Rome of his discovery. He included his discovery in his first letter on sunspots written and distributed privately in 1611/12 but which wasn’t published until 1613.

 

Galileo's Sunspot Letters

Galileo’s Sunspot Letters

Actually having phases was not a sufficient proof of Venus’ heliocentricity; the matter is in reality somewhat more complicated. If Venus were to orbit the Earth in a geocentric system between the Earth and the Sun, as proposed by Ptolemaeus, then it would also display phases. However the phases of the two configurations differ substantially so the accurate observation of those phases is a true experimentum crucis, in Francis Bacon’s sense, between a geocentric and a heliocentric Venus. What Galileo had in fact observed were phases consistent with a heliocentric orbit for Venus.

 

The Phases of Venus in both systems

The Phases of Venus in both systems

Independently of Galileo, Harriot, Marius and the Collegio Romano astronomers also observed the phases of Venus so there was no doubt that Venus and, by analogy, probably Mercury, (the phases of Mercury were first observed by the Jesuit astronomer Giovanni Battista Zupi in 1639) orbited the Sun and not the Earth. Harriot as usual did not publish, Marius sent his discovery to Kepler who published it in the preface of his Dioptrice in 1611. Odo von Maelcote included the Jesuit confirmation of Galileo’s observations in his speech during the banquet to honour Galileo at the Collegio Romano in 1611.

This discovery put an end, once and for all, to a pure geocentric system à la Ptolemaeus but did not as Castelli thought, in his letter to Galileo, provide definitive proof of Copernicus’ heliocentric system. Both the ancient Heracleidian and Tycho’s helio-geocentric systems would display the same, newly discovered, phases of Venus. This situation is illustrated on the famous title page of Riccioli’s Almagestum Novum (1651), which shows Ptolemaeus lying on the ground with his system, feebly claiming, “I will rise again” whilst Urania weighs the merits of the Copernican heliocentric system against those of Riccioli’s own semi-Tychonic system. In Riccioli’s system Mercury, Venus and Mars orbit the Sun, which in turn, together with Jupiter and Saturn, orbits the Earth. As far as I know, nobody other than Riccioli ever propagated this strange beast.

 

Title page Riccioli’s Almagestum Novum (1651)

Title page Riccioli’s Almagestum Novum (1651)

Although the phases of Venus were not decisive in deciding the conflict between the supporters of geocentricity and those of heliocentricity they did provide an important step along the twisting road towards the eventual acceptance of a heliocentric model, Kepler’s, for the then known cosmos.

 

h/t to my #histsci soul sister Rebekah “Becky” Higgitt whose questions on this topic on Twitter inspired this post.

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Science grows on the fertilizer of disagreement

At the weekend German television presented me with all three episodes of Jim Al-Khalili’s documentary on the history of electricity, Shock and Awe: The Story of Electricity. On the whole I found it rather tedious largely because I don’t like my science or history of science served up by a star presenter who is the centre of the action rather than the science itself, a common situation with the documentaries of ‘he who shall not be named’-TPBoPS, and NdGT. It seems that we are supposed to learn whatever it is that the documentary nominally offers by zooming in on the thoughtful features of the presenter, viewing his skilfully lit profile or following him as he walks purposefully, thoughtfully, meaningfully or pensively through the landscape. What comes out is “The Brian/Neil/Jim Show” with added science on the side, which doesn’t really convince me, but maybe I’m just getting old.

However my criticism of the production style of modern television science programmes is not the real aim of this post, I’m much more interested in the core of the first episode of Al-Khalili’s documentary. The episode opened and closed with the story of Humphrey Davy constructing the, then, largest battery in the world in the cellars of the Royal Institution in order to make the first ever public demonstration of an arc lamp and thus to spark the developments that would eventually lead to electric lighting. Having started here the programme moved back in time to the electrical experiments of Francis Hauksbee at the Royal Society under the auspices of Isaac Newton. Al-Khalili then followed the development of electrical research through the eighteenth-century, presenting the work of the usual suspects, Steven Gray, Benjamin Franklin etc., until we arrived at the scientific dispute between the two great Italian physicists Luigi Galvani and Alessandro Volta that resulted in the invention of the Voltaic pile, the forerunner of the battery and the first producer of an consistent electrochemical current. All of this was OK and I have no real criticisms, although I was slightly irked by constant references to ‘Hauksbee’s’ generator when the instrument in question was an adaption suggested by Newton of an invention from Otto von Guericke, who didn’t get a single name check. What did irritate me and inspired this post was the framing of the Galvani-Volta dispute.

Al-Khalili, a gnu atheist of the milder variety, presented this as a conflict between irrational religious persuasion, Galvani, and rational scientific heuristic, Volta, culminating in a victory for science over religion. In choosing so to present this historical episode Al-Khalili, in my opinion, missed a much more important message in scientific methodology, which was in fact spelt out in the fairly detailed presentation of the successive stages of the dispute. Galvani made his famous discovery of twitching frog’s legs and after a series of further experiments published his theory of animal electricity. Volta was initially impressed by Galvani’s work and at first accepted his theory. Upon deeper thought he decided Galvani’s interpretation of the observed phenomena was wrong and conducted his own series of result to prove Galvani wrong and establish his own theory. Volta having published his refutation of Galvani’s theory, the latter not prepared to abandon his standpoint also carried out a series of new experiments to prove his opponent wrong and his own theory right. One of these experiments led Volta to the right explanation, within the knowledge framework of the period, and to the discovery of the Voltaic pile. What we see here is a very important part of scientific methodology, researchers holding conflicting theories spurring each other on to new discoveries and deeper knowledge of the field under examination. The heuristics of the two are almost irrelevant, what is important here is the disagreement as research motor. Also very nicely illustrated is discovery as an evolutionary process spread over time rather than the infamous eureka moment.

The inspiration produced from watching Al-Khalili’s story of the invention of the battery chimes in very nicely with another post I was planning on writing. In a recent blog post, Joe Hanson of “it’s OKAY to be SMART” wrote about Galileo and the first telescopic observations of sunspots at the beginning of the seventeenth-century. The post is OK as far as it goes, even managing to give credit to Thomas Harriot and Johannes Fabricius, however it contains one truly terrible sentence that caused my heckles to rise. Hanson wrote:

Although Galileo’s published sunspot work was the most important of its day, on account of the “that’s no moon” smackdown it delivered to the Jesuit scientific community, G-dub was not the first to observe the solar speckles.

Here we have another crass example of modern anti-religious sentiment of a science writer getting in the way of sensible history of science. What we are talking about here is not the Jesuit scientific community but the single Jesuit physicist and astronomer Christoph Scheiner, who famously became embroiled in a dispute on the nature of sunspots with Galileo. Once again we also have an excellent example of scientific disagreement driving the progress of scientific research. Scheiner and Galileo discovered sunspots with their telescopes independently of each other at about the same time and it was Scheiner who first published the results of his discoveries together with an erroneous theory as to the nature of sunspots. Galileo had at this point not written up his own observations, let alone developed a theory to explain them. Spurred on by Scheiner’s publication he now proceeded to do so, challenging Scheiner’s claim that the sunspots where orbiting the sun and stating instead that they were on the solar surface. An exchange of views developed with each of the adversaries making new observations and calculations to support their own theories. Galileo was not only able to demonstrate that sunspots were on the surface of the sun but also to prove that the sun was rotating on its axis, as already hypothesised by Johannes Kepler. Scheiner, an excellent astronomer and mathematician, accepted Galileo’s proofs and graciously acknowledge defeat. However whereas Galileo now effectively gave up his solar observations Scheiner developed new sophisticated observation equipment and carried out an extensive programme of solar research in which he discovered amongst other things that the sun’s axis is tilted with respect to the ecliptic. Here again we have two first class researchers propelling each other to new important discoveries because of conflicting views on how to interpret observed phenomena.

My third example of disagreement as a driving force in scientific discovery is not one that I’ve met recently but one whose misrepresentation has annoyed me for many years, it concerns Albert Einstein and quantum mechanics. I have lost count of the number of times that I’ve read some ignorant know-it-all mocking Einstein for having rejected quantum mechanics. That Einstein vehemently rejected the so-called Copenhagen interpretation of quantum mechanics is a matter of record but his motivation for doing so and the result of that rejection is often crassly misrepresented by those eager to score one over the great Albert. Quantum mechanics as initial presented by Niels Bohr, Erwin Schrödinger, Werner Heisenberg et. al. contradicted Einstein fundamental determinist metaphysical concept of physics. It was not that he didn’t understand it, after all he had made several significant contributions to its evolution, but he didn’t believe it was a correct interpretation of the real physical world. Einstein being Einstein he didn’t just sit in the corner and sulk but actively searched for weak points in the new theory trying to demonstrate its incorrectness. There developed a to and fro between Einstein and Bohr, with the former picking holes in the theory and the latter closing them up again. Bohr is on record as saying that Einstein through his informed criticism probably contributed more to the development of the new theory than any other single physicist. The high point of Einstein’s campaign against quantum mechanics was the so-called EPR (Einstein-Podolsky-Rosen) paradox, a thought experiment, which sought to show that quantum mechanics as it stood would lead to unacceptable or even impossible consequences. On the basis of EPR the Irish physicist John Bell developed a testable theorem, which when tested showed quantum mechanics to be basically correct and Einstein wrong, a major step forward in the establishment of quantum physics. Although proved wrong in the end Einstein’s criticism of and disagreement with quantum mechanics contributed immensely to the theories evolution.

The story time popular presentations of the history of science very often presents the progress of science as a series of eureka moments achieved by solitary geniuses, their results then being gratefully accepted by the worshiping scientific community. Critics who refuse to acknowledge the truth of the new discoveries are dismissed as pitiful fools who failed to understand. In reality new theories almost always come into being in an intellectual conflict and are tested, improved and advanced by that conflict, the end result being the product of several conflicting minds and opinions struggling with the phenomena to be explained over, often substantial, periods of time and are not the product of a flash of inspiration by one single genius. As the title says, science grows on the fertilizer of disagreement.

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Galileo, the Church and Heliocentricity: A Rough Guide.

A couple of days ago on Twitter, Brian Cox asked the Twitter historians, “Did Galileo know that he would annoy the Church when he published The Starry Messenger?” The very simple answer to this question is, no but a lengthy discussion of the situation developed on Twitter. It was suggested that somebody should produce a short temperate answer to the question as a reference source and after some hesitation I have acquiesced. This will be a relative short presentation of the various stages of this historical process with a minimum of explanation and justification, as Joe Friday used to say, “the facts ma’am, just the facts!” This is of course my interpretation but it is based on a fairly good knowledge of the most recent principal secondary literature on the subject and it is one that I think would find fairly general agreement amongst those who have seriously studied the subject. Those who disagree are welcome, as always, to air their views in the comments but I expect those who choose to do so to base those views on historical facts and not on prejudice.

The first thing to make clear is the situation in terms of astronomy, cosmology and the Church in the first decade of the seventeenth-century before Galileo, Marius, Harriot, Lembo and others changed our view of the cosmos forever with the recently invented telescope. Astronomy and cosmology were not very high up on the Church’s agenda between 1600 and 1610. The vast majority of people, including the experts, still believed in a geocentric cosmos in the form developed by Ptolemaeus, the most modern version being basically that of Peuerbach and Regiomontanus. A very small handful believed in the Copernican heliocentric model, and believed is the right word because it lacked any real form of empirical proof and was burdened by all the physical problems engendered by a moving earth. A probably equally small number favoured a Tychonic geo-heliocentric model with or without a rotating earth and another small number were finding favour with Gilbert’s geocentric model with a rotating earth. All of the discussions were very academic and nothing that could or would threaten the dominance of a solid Bible conform geocentricity, so nothing for the Church to get its knickers in a twist about.

The telescopic discoveries were brand new empirical evidence and the biggest shake up in astronomy since mankind first cast its little beady eyes on the heavens. When he started to make his discoveries, late in 1609, Galileo was very much aware of the fact that he was sitting on the Renaissance equivalent of a Nobel prize, a knighthood and the keys to the treasure chest all in one and also very aware that he almost certainly wasn’t the only person making or about to make these discoveries. In the last point he was of course completely right, Harriot was ahead of him and Marius was breathing down his neck. Galileo was fully aware that if his wished to cash in then he had to get his priority claim in tout suite.

To understand this one needs to look at Galileo’s situation. In 1610 he was a forty-six year old professor of mathematics, stuck in the same rather lowly position for the last eighteen years. He was on the down hill slope to ill health, death and anonymity. He had already done his ground-breaking work on dynamics but hadn’t published it. If he were to die tomorrow nobody would remember him beyond a few close friends and his family. Now he had hit the jackpot and needed to cash in fast. He bunged his principal discoveries together in book form, in what was more a press release than a scientific report, the Sidereus Nuncius, and had it printed and published as fast as possible.

The last thing the Galileo wanted to do at this point was to annoy anybody; he wanted fame and fortune not infamy. He spent as much effort on getting permission to dedicate his small book to Cosimo Medici, the ruler of the Duchy of Florence, his home province, and his sometime private pupil, as he did on his telescopic observations. He also made very sure that the Medici would approve of the name he gave to the newly discovered moons of Jupiter; he was after preferment, which he got as a result of his clever tactical manoeuvring. He would have been mortified if his publication had caused problems with the Church in Rome because that would almost certainly have cost him any chance of an appointment to the Medici court, his main aim at the time. The Medici did in fact drop him when he finally collided with the Church in the 1620s.

The telescopic discoveries, which Galileo was the first to publish, shook up the whole of Europe and not just the Catholic Church. However the contents of Sidereus Nuncius neither disproved Ptolemaeus/Peuerbach nor did they prove Copernicus, as I’ve already explained here. Of course at first they did nothing at all because like all new scientific discoveries they needed to be confirmed by other astronomers. This proved to be somewhat difficult, as the available telescopes were very poor quality and Galileo was an exceptional telescopic observer. In the end it was the Church’s own official astronomers, the members of Clavius’ mathematical research group at the Collegio Romano, who with the active assistance of Galileo delivered the necessary confirmation of all of Galileo’s discoveries.

Hailed now as the greatest astronomer in Europe Galileo travelled in triumph to Rome where he was feted by the mathematicians of the Collegio Romano, who threw a banquet in his honour, had an audience with the Pope and was appointed a member of the Accademia dei Lincei who also threw a banquet in his honour. No signs of annoyance here. Galileo was appointed philosophicus and mathematicus to the Medici court in Florence, as well as professor for mathematics without teaching obligations at the University in Pisa. The humble insignificant mathematician had become a renowned social figure, almost overnight, feted and praised throughout Europe. High Church officials flocked to make his acquaintance and win his friendship, one of these, the Cardinal Maffeo Barberini, became a close friend and the cause of Galileo’s downfall later in his life.

Although nothing in the Sidereus Nuncius disproved the geocentric model of Ptolemaeus the discovery of the phases of Venus a short time later, by Galileo, Lembo, Harriot and Marius, did. The basic geocentric model was dead in the water and the Church had a problem because Holy Scripture clearly implied a geocentric cosmos. Riding on the wave of his fame Galileo wanted to go for the big one. He wanted to go down in history as the man who proved that the cosmos was heliocentric. Unfortunately he lacked a genuine proof. He had evidence that the cosmos was not geocentric and not homocentric but all the available empirical evidence satisfied both a heliocentric cosmos and a geo-heliocentric Tychonic one and it was the latter that most astronomers, still worried about the physical problems of a moving earth, tended to favour.

Around 1613, despite his lack of genuine proof Galileo began to canvas his newly won influential friends in Rome in an attempt to convince them to give their support to a call for the acceptance of a heliocentric cosmos, a dangerous move. The Church was a vast structure set in its ways and like a large ocean liner getting it to stop in full motion and reverse its direction was something that required a lot of time and space, Galileo eager to make his mark in history lacked the necessary patience to wait for the Church to accept the inevitable and was trying to force the pace. Several of his friends including Maffeo Barbarini advised him to calm down and not to force the Church into a corner, but Galileo, his ego inflated by his recent successes failed to heed this sound advice.

In the next couple of years both Galileo and the Carmelite father Paolo Antonio Foscarini tried to tell the Church how to reinterpret those passages of the Bible that contradict a heliocentric interpretation of the cosmos. This was a fundamental failure and guaranteed to annoy the Church extremely, which it did. One should remember that all of this was taking place in the middle of the Counter Reformation and on the eve of the Thirty Years War, which would kill off between one third and two thirds of the entire population of Middle Europe in what was basically an argument about who had the right to interpret the Bible. The Church set up a commission to investigate Foscarini’s book on the subject and the commission came down very hard on heliocentricity, calling it both philosophically (read scientifically) absurd and heretical. The accusation of heresy was not confirmed by the Pope and so was never official Church doctrine, but the damage was done. Cardinal Roberto Bellarmino was instructed to inform Galileo of the commission’s judgement. In a friendly chat Bellarmino did just this, informing Galileo that he could neither hold nor teach the theory that the cosmos was heliocentric. It is important to note that the theory was banned not the hypothesis. One could continue to discuss a hypothetical heliocentric cosmos, one could not, however, claim it to be fact. As many people have pointed out over the centuries this restriction was actually in line with the known empirical facts. The books of Kepler and other Protestants claiming that the cosmos was heliocentric were placed on the Index and Copernicus’ De revolutionibus was placed on the Index until corrected. Interestingly the Inquisition did just that. They removed the handful of passages from De revolutionibus that claimed the heliocentric cosmos to be fact and then gave the book free to be read, already in 1621. We still have Galileo’s personal censored copy of the book. This censorship was only really effective in Italy the rest of Europe not taking much notice of the Church’s efforts to suppress heliocentricity.

This setback did very little to slow down Galileo’s rise to fame and he became a very favoured celebrity throughout Northern Italy. Symptomatic for this is his notorious dispute with the Jesuit astronomer Orazio Grassi over the nature of comets that peaked in the publication of Galileo’s Il Saggiatore, in 1623. A dispute in which Grassi was scientifically right and Galileo wrong, but in which Galileo carried the laurels thanks to his superior polemic and the sycophantic cheers of his high powered fan club, which included the newly elected Pope, Urban VIII, Galileo’s old friend Maffeo Barberini.

Barberini’s elevation to the Holy Throne gave Galileo the chance he had been waiting and longing for, the chance to go down in history as the man who established the heliocentric cosmos. Using his friendship with the new Pope, Galileo convinced Barberini that the German Protestants were laughing at the Catholic Church because it had rejected heliocentricity because according to those dastardly Protestants the Catholics were too stupid to understand it. Beguiled by his silver tongued friend Barberini gave Galileo permission to write and publish a book in which he would present both the Ptolemaic and Copernican systems to demonstrate the deep astronomical knowledge of the Catholics but by no means was he to favour one of the systems. Galileo wrote the book, his Dialogo, in which he was anything but impartial and unbiased, as instructed, but instead left nobody in any doubt just how superior the Copernican system was in his opinion, however he still lacked any real empirical proof. Through a series of tricks he managed to get his book past the censors and into print. Galileo had erred very badly, you don’t play the most powerful absolutist ruler of your time for a fool, particularly not when that ruler is already displaying strong signs of the paranoia that, sooner or later, effects all absolutist rulers.

I’m not going to go into all of the contributory factors that played a part in the sorry mess that was Galileo’s trial by the Inquisitions, I’ll deal with those one day in another post, but it is safe to say that he got stamped on for his hubris. By comparison with other cases he didn’t actually get stamped on very hard and got off relatively lightly. I can already hear the screams of protest at the last sentence but within the context of the times and place where Galileo lived and moved it is an accurate description of his fate.

One thing that should be made very clear when discussing this whole sorry mess is that Galileo was never the fearless defender of scientific truth or freedom of speech that his modern fan club like to present him as. He was an extremely egotistical social climber with an eye on the main chance, his own undying fame. Through his ill-considered actions he achieved his goal but not quite in the way he had intended.

It is ironic that many people today still believe erroneously that Galileo actually proved the reality of a heliocentric cosmos in his Sidereus Nuncius.

[The original opening paragraph of this post was modified at the request of those who wish it to be used as a short simple reference source]

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