Talk:Galileo Galilei/Archive 10

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Naming: Galileo vs. Galilei

This seems a trivial concern compared to all the other threads here, but perhaps someone has insight into it anyway: is there any particular reason that authors in the Anglo-Saxon context always use Galileo Galilei's first name (i.e. Galileo) when abbreviating, whereas in all the other languages familiar to me (German, French, Italian, Russian), his last name is used (i.e. Galilei).

85.178.4.210 (talk) 10:55, 2 November 2008 (UTC)

The final claim is certainly not true for Italian, which is where the English custom has probably come from. See the Italian Wikipedia article on Galileo, for instance. Galileo is the last of a few great Tuscans whom the Italians have traditionally referred to by their first names. Others include Dante, Leonardo and Michelangelo.

—David Wilson (talk · cont) 13:57, 3 November 2008 (UTC)

The final claim is not "not true" — but it is not complete. The Italian Wikipedia article on Galileo Galilei uses both "Galilei" alone and "Galileo" alone. However, the first correspondent is arguably more correct, judging by the exclusive usage of "Galilei" in the most critical portions, namely the sub-headings: viz. "Galilei a Roma", "Galilei e la scienza", "Galilei e l'arte", and "Galilei e la musica". Simply "Galilei" is used in other Italian articles too, such as Filippo Salviati. Hence David Wilson's speculation that this is the source of English custom is a little shaky.

The Italian conventions regarding Galileo Galilei are in contrast to Leonardo da Vinci (to my admitted surprise), in which only "Leonardo" appears in the sub-headings. Of course, in English "da Vinci" is common. It is less surprising for Dante and Michelangelo, where English and Italian conventions are alike.

If I may be permitted my own speculation, and acknowledging my limited grasp of Italian, I might point out that Michelangelo's further names mean something like "of Lodovico Buonarroti Simoni" while Dante's apparently could stem from "of Alagheriis", and Da Vinci can be rendered as "of Vinci".

This does not seem to apply to the family name Galilei. On the other hand, in English (but perhaps less so or not at all in Italian) Galileo Galilei was sometimes called "Galilieo of Pisa" (e.g. 'A Condensed History of Modern Times', 2008, p. 100, 'An Outline of Religion', 2005, p. 495. If this was common, then it would explain the tendency in English to refer to Galileo Galilei as simply "Galileo". Obviously it would be very odd to refer to him instead as just "of Pisa", because this is clearly not an established family name.

Personally I would rather the article was changed to either use the full name or just "Galilei". But I suspect there won't be many other supporters for that.

—DIV (128.250.80.15 (talk) 00:01, 29 January 2009 (UTC))

Request to remove paragraph

While there is no doubt that Pope Urban VIII and the vast majority of Church officials did not believe in heliocentrism, heliocentrism was never formally or officially condemned by the Catholic Church, except insofar as it held (for instance, in the formal condemnation of Galileo) that "The proposition that the sun is in the center of the world and immovable from its place is absurd, philosophically false, and formally heretical; because it is expressly contrary to Holy Scriptures", and the converse as to the Sun's not revolving around the Earth.

This paragraph seems to contradict itself and use fancy words to avoid a point and/or shift blame. They are saying they did not officially condemn it, but the paragraph cites there directly that they DID condemn it. The term "officially" is a political word that does not belong here. Argument can be made either way that "officially" means either said by the Pope himself and only him, or it could be said that "officially" means said by any decently high official in the church. The quote clearly condemns the helocentrism which is by definition "sun-centered view." The church then goes on to shove blame from themselves and on to the bible in one smooth move. Which is why I say this paragraph doesn't really belong in a historical/scientific article. Discuss. —Preceding unsigned comment added by Ergzay (talk • contribs) 21:42, 20 November 2008 (UTC)

I have gone ahead and removed the paragraph as a blatant violation of Wikipedia's policy on neutral point of view. I see no reasonable grounds for denying that the 1616 decree of the Congregation of the Index, or the Inquisition's 1633 judgement against Galileo, constituted "official" pronouncements against heliocentrism by the Catholic Church. One might possibly raise quibbles about calling either of them a "condemnation", but if necessary I can cite any number of reliable sources which do refer to them with precisely that term. Also, the Inquisition itself, in the abjuration which it required Galileo to sign and swear to, refers to the repudiated Copernican opinion as "dottrina già dannata" (already condemned doctrine), so any complaints against use of the term "condemnation" would need to be supported with some pretty good secondary sources.

—David Wilson (talk · cont) 15:09, 21 November 2008 (UTC)

I disagree with the removal of the paragraph. The above quote from the Galileo trial does not show that the Church condemned heliocentrism in the sense of a "sun-centered view". Instead the trial denounced the idea that the sun is in the center of the world (universe) and is immovable. I would like to see those official pronouncements against heliocentrism. Roger (talk) 01:32, 23 November 2008 (UTC)

The assertion in the deleted paragraph that "heliocentrism was never formally or officially condemned by the Catholic Church" is flatly contradicted by at least the following three impeccable sources:

On p.131 of Galileo, Bellarmine, and the Bible, Richard Blackwell refers to the Congregation of the Index's edict of 1616 as "the condemnation of heliocentrism in 1616".
On p.204 of The Church and Galileo (a collection of essays edited by Fr. Ernan McMullin), Francesco Beretta similarly refers to the Church's actions during the Galileo affair as "the condemnation of heliocentrism", although he doesn't there identify precisely which particular action of the Church's constituted the condemnation. On pp.253–254 of the same book, however, he states that Galileo's sentence "insists that heliocentrism had been declared contrary to Scripture by the Holy See in 1616" and then refers to the declaration as "this condemnation".
On p.137–138 of the same collection of essays, Annibale Fantoli writes 'The main reason given by the sentence [i.e. the Inquisition's sentence of Galileo] for the summoning of Galileo to the Holy Office was, in fact, an infringement of the prohibition to defend the heliocentric theory, a prohibition confirmed by the Bellarmine certificate itself. That theory had been "previously condemned" and it had been declared to be so "to Galileo's face" by Bellarmine and by the Segizzi injunction.' The phrases which Fantoli here puts in quotation marks come directly from the Inquisition's sentence of Galileo.

I can give citations to several other eminent authorities (Maurice Finocchiaro, Michael Sharratt, Ernan McMullin, Irving Kelter and John Heilbron) whose views on the matter are, as far as I can tell, pretty much the same as the those of the three experts I have quoted above. All of them refer in various places to the Congregation of the Index's decree of 1616 as a "condemnation", although they do not, in any of the instances I have so far been able to find, use the word "heliocentrism" to refer to the doctrines so "condemned". They use instead various versions of the term "Copernicanism" ("Copernicanism", "Copernican opinion", "Copernican theory", "Copernican system" etc.) This difference in terminology doesn't appear to me to be significant, but since your objection appears to depend on some delicate distinction between various interpretations of the word "heliocentrism", I shall refrain from insisting that they directly contradict the deleted paragraph. Nevertheless, if you want some version of the deleted paragraph to be reinstated, you will need to support the assertion that "heliocentrism was never formally or officially condemned by the Catholic Church" with citations to some authorities whose reputations come close to matching those of the three I have cited above. Even then, Wikipedia's policy on neutral point of view would require it to be qualified as a minority POV (which I am certain it is), and accompanied by a statement of the more common scholarly POV represented by the authorities I have cited.

Roger writes:

"The above quote from the Galileo trial does not show that the Church condemned heliocentrism ..."

I agree with you on this point. However, the authorities I have cited don't rely on proof texts such as that quotation to justify their opinions. Their opinions are based on a thorough and comprehensive knowledge of all the primary documentary evidence and its historical context, including the relevant sections of canon law, the range of theological and juridical opinions held by various ecclesiastical authorities at the time, and various other relevant factors.

Roger writes:

"Instead the trial denounced the idea that the sun is in the center of the world (universe) and is immovable."

I'm afraid I don't understand the distinction you are trying to draw here. Both the Congregation of the Index's decree of 1616 and the Inquisition's judgement of 1633 did much more than censure only the proposition that sun was immobile at the centre of the universe. The proposition that the earth moved was equally censured, as was the proposition that either of those other two was compatible with Scripture. Thus, a cosmological system could only avoid being covered by the censures if it was both geostatic and heliodynamic. As far as I am aware, there are no cosmological systems satisfying these criteria which are normally referred to as "heliocentric". Tycho Brahe's theory, for instance—which didn't fall foul of the censures, and was perfectly acceptable to the Church—is normally referred to as "geoheliocentric", not "heliocentric".
—David Wilson (talk · cont) 15:24, 25 November 2008 (UTC)

You say that the Earth moving was "equally censured", but I'm not sure about that.

The source [1] says that it was "formally heretical" that the Sun is immovable and at the center of the world, and that it was "at least erroneous in faith" that the Earth moved. This suggests to me that the Galileo Tribunal was more sure that Galileo was wrong about the Sun, than about the Earth.

It seems too simplistic to say that the Church condemned heliocentrism or Copernicanism. Yes, it put the Copernicus book on the Index, but the book was allowed with 9 sentences corrected. So what do you call that "corrected" version of Copernicanism? I think that you would have to call it heliocentrism, and say that there are versions of heliocentrism that were not condemned by the Church. Roger (talk) 05:08, 26 November 2008 (UTC)

Roger wrote:

"The source [2] says that it was "formally heretical" that the Sun is immovable and at the center of the world, and that it was "at least erroneous in faith" that the Earth moved. This suggests to me that the Galileo Tribunal was more sure that Galileo was wrong about the Sun, than about the Earth."

I have outlined the main problem with this interpretation below. In fact, neither the 1616 decree of the Congregation of the Index, nor that part of the judgement against Galileo where the Inquisitors deliver their verdict, nor the abjuration which they drew up for Galileo to swear to make any distinction that I can discern between the opinion that the Sun is stationary and the one that the earth moves.

Well since it is commonly known as the Wittenberg interpretation, that is what I would normally call it. The name is something of a misnomer, since it is really a denial of an interpretation rather than being itself an "interpretation", as that term is commonly understood. Adherents to this view were willing to make use of all of the mathematical techniques expounded in De Revolutionibus, including—to use somewhat anachronistic modern terminology—a coordinate system in which the coordinates of the Sun and fixed stars remained fixed, those of the Earth's centre traced out a circle with a period of one year, and those of a point on the earth's surface traced out a circle relative to its centre with a period of one siderial day. However they quite explicitly denied that this mathematical construction constituted a true representation of physical reality, since they firmly believed that the earth was really stationary and that the sun, moon, planets and fixed stars really did revolve about it with various periods of approximately one day.

I am unaware of any instances in the scholarly literature where the Wittenberg interpretation is referred to as "a version of heliocentrism". I don't think it would be unreasonable to describe Copernicus's mathematical model as being "heliocentric", regardless of how it is interpreted, but to the best of my knowledge, the noun "heliocentrism" is only ever used to refer to theories in which the rotation of the earth on its axis and its revolution around the Sun are regarded as physically real. If you know of any exceptions, please cite them.

I am aware of at least one instance where the Wittenberg interpretation has been referred to as "this version of Copernicanism". But again, as far as I can tell, such usage only ever occurs when the Wittenberg interpretation is being specifically discussed. Otherwise, the term "Copernicanism" seems to be only ever used to refer to the standard version in which the motions of the earth are explicity considered to be physically real.

If anyone wants to add an accurate and properly sourced description of the Wittenberg interpretation to the article, along with a statement that the Catholic Church's censures did not apply to it, then I would have no objections, although I think the Galileo affair article would be a more appropriate place for it.

—David Wilson (talk · cont) 12:06, 29 November 2008 (UTC)

Simplicio="stupid"?

I have queried the attribution in the article of the meaning "stupid" to the name, "Simplicio", of the character in Galileo's Dialogue who supports Aristotelianism. While I can attest to having seen this attribution before, it has always been in tertiary sources of at least questionable reliability on such matters of detail (such as Galileo, Darwin, and Hawking, for example) and never accompanied by a citation to a more authoritative source. I have also never seen this attribution made in the scholarly secondary literature (or in the primary literature for that matter).

In the preface to the Dialogue Galileo claimed to be naming Simplicio after Simplicius of Cilicia, a 6th century philosopher and commentator on the works of Aristotle. Neither "Simplicio" nor "Simplicius" appear to be actual words in their respective languages of Italian or Latin. I could find neither of them in them in the comprehensive dictionaries of those languages I consulted (Zingarelli—but 2007, rather than 2009—for Italian, and the on-line Lewis and Short for Latin).

"Simplicio" has the cognates "semplice", "semplicione" and "sempliciotto", all of which can serve as either adjectives or nouns. As an adjective "semplice" has roughly the same range of meanings as the English word "simple". However, while it can mean "foolish" when applied to a person, it has acquired that meaning (according to Zingarelli, at least) by extension of its more usual senses of "sincere", "ingenuous", "artless" etc. As a noun, "semplice" means a person who is ingenuous, artless, or often naive and foolish. "Semplicione" has only the approbatory senses of "ingenuous, sincere and good-natured", or a person with those qualities, and "sempliciotto" has only the pejorative senses of "naive and credulous", or a person with those qualities.

In Latin, neither of the cognates of "Simplicius" I was able to find in Lewis and Short (namely "simplex" and "simplicitas") meant anything like "stupid", "fool", "foolishness", "stupidity", or similar.

In view of all this, I believe the claim that "Simplicio" means "stupid" requires support from a more credible source than any (such as the one I have linked to above, for instance) that I have so far been able to dig up
—David Wilson (talk · cont) 14:32, 23 November 2008 (UTC)

How about saying "simpleton" instead of "stupid"? Roger (talk) 22:39, 23 November 2008 (UTC)

Simply replacing "stupid" with another word with a slightly different meaning doesn't solve the problem. The issue is not which particular derogatory word is most appropriate, but whether "Simplicio" does in fact have any such derogatory meaning. As far as I have been able to determine, there is no evidence that it does.

Please also note also that I am not contesting the fact that Galileo portrayed Simplicio as a fool, which is easily documentable by any number of reliable sources.

—David Wilson (talk · cont) 15:53, 25 November 2008 (UTC)

So Galileo creates a simple-minded character, and calls him Simplicio. Is that just coincidence? Isn't it obvious that the name was intended to be descriptive? Roger (talk) 05:08, 26 November 2008 (UTC)

"Formal Heresy" of Sun's Immobility

I have removed tne following assertion:

the idea that the Sun is stationary was condemned as "formally heretical."^[87]

from the article as both original research and a non-neutral point of view.

The source cited in support of the assertion comprises two collections of translated extracts from the judgement and sentence from Galileo's trial. Both are misleading because they omit crucial context, in one case without even indicating that it has been omitted. A complete copy of the original judgement can be found here (in Italian), and Maurice Finocchario's complete English translation from his book The Galileo Affair can be found here.

When this document is read in its entirety, it is evident that the quotation where the immobility of the Sun is declared formally heretical appears as part of a general account of the events of 1615-1616, and is merely given as a description of part of the advice which theological consultors had given to the Pope and the Holy Office (aka the Inquisition) at that time. But that part of the consultors' advice was not adopted by the Pope (then Paul V) or the Holy Office as the Church's official view on the matter at that time, and there is no clear indication in the description of those events given in the judgement against Galileo that his judges had decided to adopt it as their own view either. Therefore, unless a reliable secondary source can be found to support the above-quoted assertion, its inclusion in the article is unwarranted.

Moreover, there are at least some eminent scholars^[1] who have argued that the Inquisition's judgement against Galileo did not in fact declare the immobility of the Sun, or any other part of Copernican doctrine, to be heretical, and there is at least one other that I know of (John Heilbron^[2]) who seems to think that the judgement wasn't sufficiently clearly written to determine whether or not it had actually declared any part of Copernican doctrine to be formally heretical. My impression (which may well be mistaken, however) is that this opinion is actually more common among scholars of the Galileo affair than the one I have removed from the article. But in any case, including only the opinion that the Inquisition's judgement against Galileo had declared the immobility of the Sun to be heretical would clearly not satisfy Wikipedia's requirements for a neutral point of view. If the article is to include citations to that opinion then it must also include ones to the contrary opinion.

Notes
1^ Annibale Fantoli, for instance, on pages 139–143 of the collection of essays The Church and Galileo, edited by Ernan McMullin.
2^ Heilbron's analysis is on pages 281–284 of The Church and Galileo.
—David Wilson (talk · cont) 16:30, 28 November 2008 (UTC)

Legacy

The same sentence occurs twice in the paragraph entitled "Legacy".
—Preceding unsigned comment added by 217.41.51.240 (talk) 20:40, December 2, 2008

Thanks for the tipoff. Iv'e now fixed it.

Please remember to sign your comments. It's very easy to do by simply typing four tildes at the end of the comment. There is also no point in not doing so, because anyone can easily find all the information that would be contained in the signature just by checking the history of the talk page.

—David Wilson (talk · cont) 13:26, 2 December 2008 (UTC)

Further vandalism

The moment that the article was unprotected, it was flooded with further vandalism. —Preceding unsigned comment added by 81.158.207.21 (talk) 10:39, 17 December 2008 (UTC)

Sloppy writing

The article says "In 1609, Galileo was among the first to use a refracting telescope as an instrument to observe stars, planets or moons." What does "...among the first..." mean? Was he the first, or was he not? If he was the first, then it should be made clear. If he was not, the name of the one who was the first, should be mentioned. 80.202.40.85 (talk) 19:18, 31 December 2008 (UTC)

It is very hard to ascertain exactly who was the first to try the obvious idea of turning the telescope on the sky. —Preceding unsigned comment added by 81.149.223.218 (talk) 16:28, 6 January 2009 (UTC)

Simon Marius and Thomas Harriot have been mentioned. —Preceding unsigned comment added by 81.158.207.21 (talk) 10:43, 8 January 2009 (UTC)

Was Galileo not the first to turn the telescope to the sky and record his findings though? Jdrewitt (talk) 10:46, 8 January 2009 (UTC)

Try making a statement, not asking questions. —Preceding unsigned comment added by 81.158.207.21 (talk) 10:09, 9 January 2009 (UTC)

Try being less rude, this is a talk page where we discuss the article, it is perfectly valid to ask questions here. Jdrewitt (talk) 13:06, 9 January 2009 (UTC)

Galileo's Cantilever Beam

Hi, I'm new to Wikipedia so sorry if I've overlooked something. I just thought I'd mention that I did not notice anything on Galileo's Cantilever Beam - his research and findings. Any reasons for this, or is it just it has been overlooked until now? --Dingodave1 (talk) 11:28, 7 January 2009 (UTC)

Do you mean his writings in The Little Balance (1586). This is mentioned in his writings section, possible expansion may be needed, if you have knowledge on this feel free to help out. However The Little Balance article would be a better place to discuss his findings in fine detail, the article does not yet exist but feel free to create it. Jdrewitt (talk) 18:12, 9 January 2009 (UTC)

I think it is not in that book as that book is about weighing materials in air and then liquids or something along those lines? I think it might have come from his writings 'Dialogues Concerning Two New Sciences' (1638), which is not mentioned in the article. I do not know a great amount about Galileo's Cantilever Beam only the very basic principles and that there were many inaccuracies in his work on it for example he did not take into account the flexability of the wooden beam into his theorem. Basically the experiment he conducted consisted of a wooden beam attached to a wall at one end and a boulder hanging from the other acting as a 'Cantilever Beam', Galileo investigated into the behaviour of the beam; how the forces were distributed, where along the beam it would break and why it would break at that point, most probably more questions aswell. The reasoning behind his investigation was to do with the failing of wooden ships and marble colums at the time.

Again i do not know a great amount about this but from what ive gathered one of the 'new sciences' from 'Dialogues Concerning Two New Sciences' by Galileo, layed down some of the basic principles of material science, regarding the strength of materials.--Dingodave1 (talk) 00:41, 10 January 2009 (UTC)

Yes, the Little Balance basically uses the archimede's principle. However it does include a 'beam' with a counter weight which is why I thought it might have been the cantilever beam you mentioned but evidently not. The article does mention the publication of Galileo's Discourses and Mathematical Demonstrations Relating to Two New Sciences but does not go on to discuss its contents - it might be prudent to add this was the ultimate publication of his work over the preceding 30 years. The Two New Sciences article currently makes no reference to the cantilever beam, but it needs extensive expansion. If you have sources feel free to add the information to the article. Jdrewitt (talk) 10:04, 10 January 2009 (UTC)

Not the first to map the Moon with a telescope

According to this Galileo was not the first to map the Moon with a telescope. Thomas Harriot was first. Bubba73 (talk), 22:24, 15 January 2009 (UTC)

galileo galileo

Galileo was born on February 15 1564 at Pisa and died on January 8, 1642 at Arcetri, near Florence. He was an Italian Mathematician, astronomer and physicist and is considered as the founder of the experimental method. —Preceding unsigned comment added by 76.238.158.116 (talk) 04:24, 23 January 2009 (UTC)

Protestant support for Copernican theory

In his book, Born to Rebel, Frank J. Sullivan, an MIT scientist (not a historian) believes, based on his data, that there was no more sympathy for Copernican theory at the time among Protestants (page 210). Of course, there was no opportunity nor venue to try him in a Protestant country. A bit ironic that has been one of the main Protestant complaints against Catholics! There doesn't seem to be any place for this data in the article. Student7 (talk) 00:52, 28 January 2009 (UTC)

Galileo and relativity

I would like a sentence in the opening paragraph mentioning Galileo as the first to formulate a principle of relativity. This is a far greater contribution to physics than the motion of accelerated bodies, and is recognized by today's physicists as one of the grand all-encompassing principles of physics. Except for the point that the speed of light is frame independent (which Galileo could not have possibly known with the technology of his time), Galileo's grasp of the principle is as deep as Einstein's.

Olaf3142 (talk) 23:33, 12 February 2009 (UTC)Olaf3142

Ok, we do have an article on Galilean relativity although it is not well referenced. Do you have a reliable source to back this up. If so, I think it would be useful to include in the lead section with a link to Galilean relativity in the sentence describing his contributions, leaving inclusion of the details of the theory to the appropriate article. Jdrewitt (talk) 16:29, 16 February 2009 (UTC)

Please also note, Galilean relativity is already linked in the Physics section but again lacks a citation. Jdrewitt (talk) 16:33, 16 February 2009 (UTC)

Galileo and Joshua 10:13

I don't see a work cited to show conclusively that Galileo openly questioned the Joshua 10:13 passage (where God miraculously causes the sun to stand still). In fact, if you look at his letter to the Grand Duchess Christina (http://www.galilean-library.org/manuscript.php?postid=43841), you'll see that he makes an argument that the miracle fits the Copernican (i.e. heliocentric) model better than the Ptolemaic (geocentric).

Feel free to email removed with questions. —Preceding unsigned comment added by 72.72.218.24 (talk) 04:00, 15 February 2009 (UTC)

I removed your email per wikipedia guidelines Jdrewitt (talk) 09:22, 15 February 2009 (UTC).

::What's your point, maybe Galileo still believed in miracles but so what? Since the apparant motion of the sun is caused by the earth spinning on its axis, what you propose would require a complete cessation of the earth's spin. This is in clear violation of Newton's law BTW, this is not a forum. Jdrewitt (talk) 09:33, 15 February 2009 (UTC)

The IP's point is that the statement "Galileo did, however, openly question the veracity of the Book of Joshua (10:13) ... " which currently appears in the article is not only not supported with a citation to a reliable source, it is in fact unsupportable because it's demonstrably false. More to the point, though, for Wikipedia's purposes, is that its inaccuracy can easlly be verified by consulting any number of reliable secondary sources. Correcting this passage is a task I have kept putting off for some time. I'll see if I can get around to doing it later tonight. BTW, I can see no evidence that the IP was using this talk page as a forum.

—David Wilson (talk · cont)

Sorry, I mis-interpreted what the IP was saying, thank you for clarifying this. Jdrewitt (talk) 11:07, 15 February 2009 (UTC) BTW, I probably shouldn't have accused the OP for starting a forum, I meant this had the potential for growing into a discussion not relevant to the article but that's probably my fault not the OP, sorry about that :)

Semibroken Link

{{editsemiprotected}} Done. I have removed the three wikilinks to non-existent sections in the Assayer article. —David Wilson (talk · cont) 02:14, 1 March 2009 (UTC)

In section 3.2, "Controversy over Comets and _The Assayer_", a link named "Discourse on the Comets" is supposed to link to a same-named section on the Wiki "The Assayer" page. The link just takes you to the top of "The Assayer" page, because evidently the "Discourse on the Comets" section is no longer on that page. When you disable the link, be sure to maintain the still viable "note" link, [44].

Paine Ellsworth (talk) 22:03, 28 February 2009 (UTC)

If you try to edit that section, and look at its coding, you'll see that it contains a comment that says, "This should eventually link to a section in the article on the Assayer." I interpret that to mean that the Assayer article never had a section on Discourse on the Comets. The guy who created that link just meant that he thought it should have a section on it, and he hoped that someone would add a section later. Maybe he meant to do it himself, and he just never got around to it. I checked the history, and note that the link was added by a user named David J Wilson on 22 September 2007. It appears that he's still an active contributor. You can ask him about it, if you want. - Shaheenjim (talk) 00:02, 1 March 2009 (UTC)

I'll remove the link. The article on The Assayer needs a thoroughgoing rewrite in my opinion, and at the time when I added the section on the controversy over comets I thought I would be able to do this fairly soon afterwards. Alas, Real Life has intervened, and I don't know when I will be able to find the time to do the planned rewrite.

—David Wilson (talk · cont) 01:03, 1 March 2009 (UTC)

Abjuration in the Basilica (Church) of Santa Maria sopra Minerva: location + date

I would find interesting to add three factual information to the article:

Where did Galileo abjured his scientific theses? Basilica of Santa Maria sopra Minerva, Rome.
Where the trial took place? In the adjoining monastery.
When exactly did the abjuration took place? On June 22, 1633

I would suggest to add something like one of the following, but other suggestions are welcome

Galileo Galilei read his recantation in the church of Santa Maria sopra Minerva on the 22 of June 1633 and received his sentence.

Ad-hoc citation:

Vatican Secret Archives, Proceedings Of The Trial Against Galileo Galilei (Rome, 1616, 1632-33), Holy See, retrieved 2009-03-15, After the condemnation of Galileo's scientific theses, there was (...) the abjuration pronounced by the famous native of Pisa in the Church of the Minerva on the 22nd June 1633..

Any remarks? Thanks

Alberto Fernandez Fernandez (talk) 15:39, 15 March 2009 (UTC)

editsemiprotected

Please Change "Galileo Galilei (15 February 1564[2] – 8 January 1642)^[1][3] was a Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution.(paragraph 1)" to "Galileo Galilei (15 February 1564[2] – 8 January 1642)^[1][3] was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution."

Thank you. —Preceding unsigned comment added by Mmiaosmiling (talk • contribs) 05:22, 30 March 2009 (UTC)

Done Thank you for spotting that, the change has been made. Jdrewitt (talk) 08:54, 30 March 2009 (UTC)

Changes to lead

Back in early 2007 I added some reliable sources as support for the statements then made in the lead about the religious controversy over heliocentrism. Various subsequent (unsourced) changes to the lead have rendered it incompatible with what is contained in those sources (or any other reliable sources that I know of). I have therefore now rewritten that part of the lead so that it is again properly supported by the sources given.
—David Wilson (talk · cont) 17:12, 25 April 2009 (UTC)

Galileo Galilei

He was the first person ever to discover Neptune. —Preceding unsigned comment added by 173.9.13.233 (talk) 13:59, 28 April 2009 (UTC)

If the following statement, currently made at the end of the section on his contributions to astronomy, is accurate, then it would appear to me to be something of an exaggeration to say that he "discovered Neptune".

"Galileo also observed the planet Neptune in 1612, but did not realize that it was a planet and took no particular notice of it. It appears in his notebooks as one of many unremarkable dim stars."

Do you have any specific proposal for amending this passage? If so, could you please provide some solid justification for doing so.

—David Wilson (talk · cont) 04:54, 2 May 2009 (UTC)

Removal of Galileo's Bible rebuttal

I have removed the line about Galileo questioning the veracity of Joshua 10:13, since no sources are cited to support this claim, and it appears to contradict other sources such as Galileo's letter to the Duchess Christina. Kata Markon (talk) 22:46, 8 May 2009 (UTC)Kata Markon

How about this source for the statement? The Essential Galileo
And a question for you: Was there a ^{[citation needed]} template placed after the claim for awhile before you removed it? ^.`^) Paine ^diss`cuss (^^`. 04:39, 9 May 2009 (UTC)

I can't see how any part of the text on pages 8-9 of The Essential Galileo can be read as supporting the statement: "Galileo, did, however, openly question the veracity of the Book of Joshua (10:13)...". What Galileo questioned in his Letter to Castelli, and again in his Letter to the Grand Duchess Christina, was the interpretation of that book by his philosophical opponents as contradicting Copernicanism. In both of the above mentioned letters, Galileo was careful to acknowledge that "the Holy Scripture can never lie or err" (as he puts it in his Letter to Castelli), and it is crystal clear from what he wrote that he fully believed that the miracle of Joshua did take place, essentially as described in the Bible. What he argued, as Finocchiaro indicates on page 9 of The Essential Galileo, was that if the passage from Joshua were to be interpreted absolutely literally, as his opponents maintained it had to be, then it would be inconsistent with the Ptolemaic system, and might very well be consistent with the Copernican.

There has been a previous discussion on this point back in February. While no {{fact}} template was placed on the passage at the time, Kata Markon, who seems to be well aware of the proper facts, could very reasonably have considered the occurrence of that discussion as sufficient grounds for removing the passage.

—David Wilson (talk · cont) 06:22, 9 May 2009 (UTC)

Gravity

There seems to be very little about his contributions to Gravity - some of which are fundamental, ie: the falling of differently weighted objects to the ground at the same rate etc. —Preceding unsigned comment added by 208.65.185.14 (talk) 06:14, 3 June 2009 (UTC)

Verbal stumble in Legacy's second paragraph

Done

The second paragraph of Legacy (last section before Notes) opens with "To coincide in part with Galileo's first recorded astronomical observations using a telescope, the United Nations has scheduled 2009 to be the International Year of Astronomy." I respectfully submit that the aim is to coincide with the fourth centenary of the observations in question ! Also, the usage of "in part" feels unnatural (as if a first author wrote the text without it and a later author added it as a minimal change to account for there being other factors). If the Galilean fourth centenary isn't the sole factor, perhaps: "The United Nations has scheduled 2009 as International Year of Astronomy, at least partly because it is the fourth centenary of Galileo's first recorded astronomical observations using a telescope." Giving the month and day of those observations (in so far as they are known) would clearly also be apt (the main article only gives August 29th, a demonstration of terrestrial telescopes). 84.215.6.188 (talk) 03:42, 6 June 2009 (UTC) Edward Welbourne, 2009/June/6th (the article is locked, so I cannot fix it myself).

Thank you for bring this to our attention. I have now fixed it.

—David Wilson (talk · cont) 06:11, 6 June 2009 (UTC)

Promotion of geoheliocentrism by phases of Venus

The article currently states:

"[Letters on Sunspots] also reported his 1610 telescopic confirmation of the full set of phases of Venus that refuted pure geocentrism and so promoted the 17th century conversion to geoheliocentrism.

with a citation to this web page as a supporting source. I could find nowhere on that web page (or its 2 successors) where it is stated that there even was such a thing as a "17th century conversion to geoheliocentrism", let alone that the discovery of the phases of Venus promoted it. I would have thought that that discovery would have been responsible for promoting heliocentrism just as much as geoheliocentrism, if not more so. but in any case, either claim needs to be properly sourced if it's to be included in the article.
—David Wilson (talk · cont) 17:53, 19 October 2008 (UTC)

Logicus comment:

It looks to me like this citation was not meant to justify the claim made in this sentence, but rather just to provide a link to some further online info about that book.

On the issue of actually justifying the claim made with references, I offer the following hopefully helpful discussion for consideration.

Here is a textual reference that claims the great majority of astronomers were geo-heliocentrists by 1632:

"But the title [of Galileo's 1632 Dialogo] was seriously misleading: by that time the Ptolemaic system had been largely abandoned by believers in a central Earth, and astronomers who could not accept the Sun-centred system - the great majority - were opting for the Tychonic or one of the other Earth-centred compromises on offer." p117, The Cambridge Concise History of Astronomy Michael Hoskin, CUP 1999

On empirical grounds it seems reasonable to suppose the majority conversion to geo-heliocentrism came soon after Galileo's 1613 publication of his 1610 discovery of the gibbous and full phases of Venus that refuted Ptolemaic pure geocentrism, coupled with Sizzi & others (including Galileo?) 1613 discovery of seasonally oscillating sunspot trajectories that refuted the Sun's daily orbit in favour of the Earth's daily rotation, and so most likely at the latest by 1622 when Longomontanus published his 'semi-Tychonic' model notably with a daily rotating Earth.

And here is a reference claiming that the Tychonic planetary model was still the prevailing planetary model in 1691 and also still in 1728 two years after the publication of the Principia's third edition and one year before Bradley's 1729 publication of his 1725 discovery of stellar aberration:

"In 1691 Ignace Gaston Pardies declared that the Tychonic was still the commonly accepted system, while Francesco Blanchinus reiterated this as late as 1728." The Tychonic and semi-Tychonic world systems Christine Schofield, p41 Taton & Wilson The General History of Astronomy 2A 1989

I suspect it would have been the semi-Tychonic model of Longomontanus with a daily rotating Earth that became the most popular geo-heliocentric model, with Capellan models as runner up.

Further evidence of the predominance of geo-heliocentric astronomy even in the early 18th century may be seen in the fact that such a leading scientist and astronomical observer as Ole Roemer died in 1710 still a Tychonic geocentrist.

And arguably the third 1726 edition of Newton's Principia provides further supporting evidence of the prevalence of the Tychonic model at that time inasmuch as the Phenomena of Book 3 still did not go beyond the factual assumption of the Tychonic geo-heliocentric model, most especially in its Phenomenon 3:

"The orbits of the five primary planets - Mercury, Venus, Mars, Jupiter, and Saturn - encircle the Sun." p799, Cohen & Whitman Principia 1999

as Imre Lakatos uniquely pointed out in his paper Newton's Effect on Scientific Standards, published in The Methodology of Scientific Research Programmes Eds Worrall & Currie, CUP 1978, p211.

It seems the majority conversion to pure heliocentrism most likely came after Bradley's 1729 publication of his 1725 discovery of stellar aberration that refuted all forms of geocentrism in explaining it on the twin hypotheses of the Earth's annual solar orbit and of the finite speed of light. Geocentrism had no explanation for this phenomenon. It should specifically be noted that this discovery was the result of an attempt to find stellar parallax in order to try and prove heliocentrism, but which failed to do so whilst accidentally discovering the confirmatory stellar aberration instead.

--Logicus (talk) 18:55, 13 January 2009 (UTC)

None of the sources you have cited addresses the issue of whether the discovery of the phases of Venus "promoted the 17th century conversion to geoheliocentrism". In fact, Christine Schofield, on p.41 of the The Tychonic and semi-Tychonic world systems now cited in the article in support of that statement, says "Apart from the astronomical problem of no parallax, the strongest pro-Tychonic arguments were religious." Nowhere that I can see does she give any hint that the discovery of the phases of Venus "promoted" geoheliocentrism any more than it did heliocentrism. Likewise, I could find nowhere in any of Hoskin's articles in The Cambridge Concise History of Astronomy where he does so either.

On the wider issue of whether there was any general 17th-century conversion to geoheliocentrism, not only do your sources not support it—on the contrary, they flatly contradict it. On p.123 of The Cambridge Concise History of Astronomy, Hoskin writes:

"From the publication of his [i.e. Descartes'] Principles of Philosophy in 1644, it was increasingly accepted that the Sun was one of innumerable starts in homogeneous and boundless space, and that the planets circulated about the Sun ... "

While he doesn't say precisely how rapidly Descartes' cosmology was accepted, he does say (on p.144) that by 1687, when Newton's Principia was published, it was "generally accepted".

Likewise Schofield, in the article referred to above, says (p.42) that the Tychonic system, "seemed to have little support in France", that Lutheran Germany "displayed little interest" in it, that Dutch writers hadn't "much time for it, although Huygens acknowledged its influence elsewhere", and (p.43) that in England it "never gained a strong hold". Further down on p.43 she writes:

"It is widely mentioned [N.B. she does not say "supported"] in printed books up to 1680, and there are scattered favourable references to it after that date; from 1700 onwards, however, it is normally mentioned only in order to refute it."

~~The only country where Schofield states explicitly that there was strong support for the Tychonic system is Belgium.~~ Schofield does say (p.42) that support for Tycho was "markedly stronger" in Catholic countries, "notably Italy and Belgium", but the only one she discusses in any detail at all is Belgium. Surprisingly, she doesn't say ~~much~~ anything about the other Catholic ~~countries~~ country, ~~Italy and~~ Spain, where other sources indicate that support for the Tychonic system remained strong well into the 18th century. Again, while she also says that the Jesuits "presented a united front in favour of Tycho" throughout the 17th century (p.42), she then immediately goes on to say that after 1670 many of them disguised "but thinly their preference for Copernicus."

Neither does Schofield anywhere indicate that the semi-Tychonic system received any more support than Tycho's own. On pp.38-39 she writes that Nicholaus Müller "seems to have regarded it as of equal status with the Ptolemaic and Copernican", she lists 4 English supporters of it, and says it was "referred to frequently" (N.B. not "supported" or "favourably referred to") until around 1680, "and even (scathingly) in 1717".

The Pardies and Blanchinus quotations are useless as support for the claim that there was a general 17th-century conversion to geoheliocentrism, if for no other reason than that the secondary source they have been plucked from (viz. Schofield's article) flatly contradicts them. But even if we ignore Schofield's opinions entirely, it's not difficult to find quotations from other scientists in the latter half of the 17th-century which claim that heliocentrism was the commonly accepted system at that time (Nicolaus Mercator, for example, who wrote in his Institutiones Astronomicae of 1676: "And that is why nowadays most astronomers appreciate the Copernican system as by far the most probable of all.") Such quotations cannot legitimately used on Wikipedia to support anything other than the fact that the persons so quoted have made them. Using them either as support for or opposition to a point of view (such as that there was a general 17th-century conversion to geoheliocentrism, for example) is explicity disallowed as original research by Wikipedia policy; unless, of course, a reliable secondary source cites them as evidence for that point of view—but, in this instance, that's not the case.

On the issue of Römer subscribing to geoheliocentrism, Schofield appears to be mistaken. In an article (Copernicanism in Denmark and Norway) in The Reception of Copernicus's Heliocentric Theory (Jerzy Dobrzycki ed., p.141), the author, Kristian Moesgaard, states that Römer was a Copernican, and cites a letter from him to Leibniz in which he says he was convinced that the fixed stars displayed parallactic displacements, and that he might soon be able to publish his results on that subject. Given that Schofield cites no evidence whatever for her claim that Römer subscribed to geoheliocentrism, I would tend to discount it until I have seen something more solid to support it.

Finally, in the same Wilson and Taton volume that contains Schofield's article, Albert van Helden writes (p.103):

"... by the middle of the 17th century, the Copernican issue hardly raised an eyebrow in Protestant regions. The overwhelming majority of Protestant astronomers, or at least the creative Protestant astronomers, were now Copernicans."

In view of all this, the weight of scholarly opinion would appear to me to be overwhelmingly against the assertions currently made in the article that there was a 17th-century conversion to geoheliocentrism. I therefore plan to amend those assertions over the next few days.

—David Wilson (talk · cont) 15:25, 3 May 2009 (UTC)

I have now made the appropriate changes. I did manage to find a reliable source to support the claim that the discovery of the phases of Venus promoted the adoption of geoheliocentrism in the early part of the 17th century, in the period following Galileo's discovery of them. I have taken this into account in the wording of my amendments.

—David Wilson (talk · cont) 22:50, 4 May 2009 (UTC)

Logicus to David Wilson: Thanks for these detailed critical commentaries that I have only just seen. However, unfortunately they are largely invalid, for the following reasons, thus justifying the restoration of my original texts as I recall it.

On the first issue that is the subject of this section, that of finding a justifying source for the claim that the discovery of the phases of Venus promoted the 17th century conversion to geoheliocentrism, you yourself conclude above “I did manage to find a reliable source to support the claim that the discovery of the phases of Venus promoted the adoption of geoheliocentrism in the early part of the 17th century, in the period following Galileo's discovery of them.”

So would you please kindly reveal that source to include in the article ? And I take it this means the claim can be restored with your approval ?

On the wider issue you raise here of whether there even was any general 17th-century conversion to geoheliocentrism, I suggest this issue deserves a separate new section, to which I shall copy your comments here for their further discussion, hopefully with your approval.

--Logicus (talk) 17:00, 8 July 2009 (UTC)

Is Thoren really reliable ?

Judging from Wilson’s consequential editing of the relevant passage in the article, it would seem that the reference he regards as a reliable source for the claim that Galileo’s discovery of the full phases of Venus promoted an early 17th century conversion to geo-heliocentrism is the following passage from Victor Thoren 1989 (in Taton & Wilson 1989):

“During the 17th century, therefore, after the telescopic discovery of the phases of Venus and Mars(sic!) rendered Ptolemaic cosmology untenable, professional favour tended to shift either to Tycho’s scheme or to the so called semi-Tychonic version of his disciple Longomontanus (1562-1647) and others involving a rotating Earth (see Chapter 3).”

But the citation of Mars here is surely an error. For it was surely only the telescopic discovery that Venus shows gibbous and full phases that refuted full geocentrism. But if any other planetary phases did, then it would surely be those of Mercury rather than of Mars, whose gibbous and full phases are also predicted by full geocentrism.

Such as Newton’s attempt in Phenomenon 3 of Book 3 of ‘’Principia’’ to represent the perceived phases of Mars as proof that it also orbits the Sun is surely also invalid.

On a second issue, what geoheliocentric planetary models is Thoren saying professional astronomers converted to ? Is it either to the Tychonic model, or else to Tychonic and Capellan models with a daily rotating Earth. But why include the Tychonic model without a rotating Earth on the one hand, but on the other hand exclude Capellan models without such. But moreover, in fact if Thoren really thought the phases of Mars showed it orbited the Sun, he should have excluded the simple Capellan model in favour of Riccioli’s extended Capellan model that had Mars also orbiting the Sun along with Mercury and Venus.

Of course the phases of Venus and Mars/Mercury have nothing to do with the rotating Earth issue. Rather it seems it was Sizzi’s 1613 observations of the seasonal variation in sunspot trajectories that provided the first evidential proof of the Earth’s daily rotation.

So maybe Thoren should have said:

‘During the 17th century, therefore, after the telescopic discovery of the phases of Venus and Mercury rendered Ptolemaic cosmology untenable, the great majority of astronomers converted to one of the various geo-heliocentric models – Tychonic, Capellan and Extended Capellan - that all posited at least Venus and Mercury orbited the Sun. And after Sizzi’s 1613 discovery of seasonal variation in sunspot trajectories that proved the Earth’s daily rotation, they preferred the daily rotating Earth variants of these models.’ ?

But this still raises the question of whether and when gibbous and full phases of Mercury were first observed. Presumably phases of Venus do not also prove Mercury orbits the Sun as well as Venus.

Whaddyuthink ?

Logicus did not cite this potentislly supportive source due to its apparent confusion. But maybe Wilson is right that it should be cited, once corrected ?

--Logicus (talk) 21:31, 9 July 2009 (UTC)

Revised by Logicus --Logicus (talk) 18:21, 10 July 2009 (UTC)

Thoren's inclusion of the phases of Mars as one of the phenomena which made Ptolemaic heliocentrism untenable is a bit of a puzzle. I'm embarrassed to have to admit that I didn't even notice it.

Logicus wrote:

"So maybe Thoren should have said:

‘During the 17th century, therefore, after the telescopic discovery of the phases of Venus and Mercury rendered Ptolemaic cosmology untenable, ... ' "

The problem with this is that the phases of Mercury weren't observed until 1639 (by Giovanni Zupi), when Galileo was already blind, and the Ptolemaic system had long been abandoned. I think it's more likely that Thoren was thinking of Galileo's possible detection of a phase of Mars in 1610.

In the Ptolemaic system, the maximum possible percentage of the disc of Mars that could be covered in darkness when viewed from the Earth would be about 4%, which would almost certainly have been impossible for Galileo to detect with the telescopes he had. On the other hand, in the Copernican system the percentage covered in darkness rises to more than 12% near quadrature, which might possibly have been detectable.

The problem with this explanation is that:

Galileo's observations were so ambiguous that he wasn't even sure whether they really did indicate a phase of Mars, or simply that it was not quite spherical;
Neither Galileo nor anyone else at the time, as far as I am aware, cited observations of the phases of Mars as a reason for rejecting the Ptolemaic system.

In a remark since revised Logicus wrote:

" ... it was the telescopic discovery that Venus and ‘’Mercury’’ have gibbous and full phases, but not Mars, that refuted pure geocentrism. ... . For Ptolemaic pure geocentrism predicts just the same set of phases of Mars as heliocentrism does."

No, the last sentence is incorrect, as I have already indicated above. And if it is true that observations of the phases of Venus refute Ptolemaic geocentrism, then it is also true that observations of the phases of Mars could (at least in theory) also have refuted it.

The crucial issue is exactly what one means by "Ptolemaic geocentrism". A very good case can be made out, as Kepler did in an appendix to his Hyperaspistes, that the Ptolemaic system need not have been required to use to the traditional system of rigid spheres and shells which supposedly moved the planets around, and that without that requirement it was just as capable of explaining the observed phases of all the planets, including Venus and Mercury, as all the other astronomical systems then on offer. Thus, if one takes this view, even the observations of the full set of phases of Venus did not, in fact, refute "Ptolemaic geocentrism".

It is true that if one insists that the "Ptolemaic system" must strictly adhere to the rule of embedding the planets in rigid spheres that carry them round their main epicycles, and embedding those in turn in rigid spherical shells which carry them around their deferents, then, but only then, are Venus and Mercury prevented from going around the Sun. But if one does insist on that condition, then it also forces limitations on the range of phases that can be displayed by the outer planets, and these are quite a bit smaller than those predicted by the Copernican system. So if one does actually observe the full range of phases of an outer planet that are predicted by the Copernican system, then that would refute this strict version of Ptolemaic geocentrism just as much as observations of the full set of phases of Venus does.

—David Wilson (talk · cont) 17:21, 11 July 2009 (UTC)

"Stephen Hawking says"

In the intro, he says ... But he also says that Karl Popper is one of the best proponents of logical positivism, while he in fact is its most important detractors. Hawking is a physicist and an astronomer, neither a philosopher nor a science historician. I propose the stmt is put somewhere far below the intro, deep in the text. ... said: Rursus (bork²) 12:10, 15 June 2009 (UTC)

Church controversy POVvinesses

IMHO the section Church controversy is not quite eligible for POV-check, since a neutral message can be perceived when the ear filters are fully running, but the tone seems to take the Papal opinion as an emotional axiom, such as:

To add insult to injury, Galileo put the..

and:

nor the blatant bias,

add "according to papal view" cut away the "blatant" and replace with "clearly apparent". The text is generally acceptable, but there are a few POVvy formulation fixes to be done here and there. IMHO. ... said: Rursus (bork²) 13:23, 15 June 2009 (UTC)

I wonder how Bruno would have felt about this. ^.`^) Paine Ellsworth ^diss`cuss (^^`. 11:46, 13 July 2009 (UTC)

Relevance of link?

In the third paragraph of the legacy section, there's a link to a "21st century drama on his life" apparently by a Robert Lalonde, added back in February by Neojacob. Either the author is significant enough for the author's name to be mentioned in the main text (unlikely, considering the author isn't even notable enough for a Wikipedia entry), or the drama in question isn't significant enough to merit mentioning in an article about Galileo. (I don't have an account, or I'd just "be bold" and delete the sentence in question) 86.22.74.23 (talk) 19:28, 27 June 2009 (UTC)

Sometimes redlinks are added by someone who is either planning or hoping for an article on the redlinked subject. IOW, the absence of an article does not necessarily mean that the subject is not notable. ^.`^) Paine Ellsworth ^diss`cuss (^^`. 11:49, 13 July 2009 (UTC)

Was 17th century astronomy never geo-heliocentrist ?

There seem to be two issues raised by the previous discussion immediately above of the currency of geo-heliocentrism in the 17th century, namely (1) Was there a (great) majority conversion of astronomers (or of some other constituency) from pure geocentrism to geo-heliocentrism in the 17th century and if so when was it ?, and (2) if so, when did the subsequent (great) majority or unanimous conversion from geo-heliocentrism to pure heliocentrism occur ?

The issue of two competing models here of the structure of the heliocentric revolution as a great majority or unanimity conversion of the scientific community from pure geocentrism to pure heliocentrism is that of whether this was a one-stage process, or a two-stage process with an intermediate first stage of conversion to geo-heliocentrism from pure geocentrism before a second stage conversion from geoheliocentrism to pure heliocentrism. Such as Hoskin (and others) clearly favour the 2 stage model. The key question here about this model is when the first conversion occurred, and how long it lasted before the final conversion to heliocentrism.

But Wilson’s view of scholars’ opinion based on his research presented above is that “the weight of scholarly opinion would appear to me to be overwhelmingly against the assertions currently made in the article that there was a 17th-century conversion to geoheliocentrism.” So Wilson concludes scholarly opinion is overwhelmingly against the two-stage model, and thus, contra Hoskin, that there was no period in which the great majority of the scientific community were geoheliocentrists. But Wilson’s conclusion is logically invalid, as demonstrated by the following emboldened critical commentary on his comments in square brackets.

“On the wider issue of whether there was any general 17th-century conversion to geoheliocentrism, not only do your sources not support it, on the contrary, they flatly contradict it. On p.123 of The Cambridge Concise History of Astronomy, Hoskin writes:

“From the publication of his [i.e. Descartes'] Principles of Philosophy in 1644, it was increasingly accepted that the Sun was one of innumerable starts in homogeneous and boundless space, and that the planets circulated about the Sun ... “

[FALSE. This quote does not contradict the claim that there was a 17th century conversion to geoheliocentrism in any way, and as Hoskin says as quoted above: “...by that time [i.e. 1632] the Ptolemaic system had been largely abandoned by believers in a central Earth, and astronomers who could not accept the Sun-centred system - the great majority - were opting for the Tychonic or one of the other Earth-centred compromises on offer." p117, The Cambridge Concise History of Astronomy Michael Hoskin, CUP 1999. So Hoskin clearly claims there was a 17th century conversion to geo-heliocentrism, albeit he does not date when it was first achieved. (I reckon by 1620 at the latest.) Nor does he give any clue as to how long geo-heliocentrism lasted before there was then a conversion to pure heliocentrism. His claim of an increasing acceptance of heliocentrism after 1644 is perfectly compatible with a great majority or unanimous conversion to it not being achieved before 1730, for example.]

While he doesn’t say precisely how rapidly Descartes' cosmology was accepted, he does say (on p.144) that by 1687, when Newton's Principia was published, it was "generally accepted". [No, he does not say Descartes' cosmology nor heliocentrism were generally accepted by 1687 on p144, nor anywhere else. Rather he says: "Newton's Principia appeared in 1687. [Its title Mathematical Principles of Natural Philosophy] ...was a clear challenge to the generally accepted view of nature, as embodied in Descartes' systematic textbook Principles of Philosophy." But Descartes' 'view of nature' surely refers to his mechanist philosophy of nature here, rather than his cosmology and/or heliocentrism. Thus it was surely Descartes' mechanistic philosophy of nature he claims was accepted by 1687, rather than his cosmology and specifically heliocentric planetary model in particular. ]

[It should be noted re Wilson’s following reportage of Schofield comments on support for the Tychonic model that the issue here is rather support for geo-heliocentrism in general, which had 4 different models, namely Tychonic, semi-Tychonic, Capellan (Bacon) and Extended Capellan (Riccioli), and not just for the Tychonic model as Wilson invalidly presumes. None of the following Schofield negative claims about support for the Tychonic system contradict the claim that there was a period of geoheliocentrism, and however brief.]

Likewise Schofield, in the article referred to above, says (p.42) that the Tychonic system, seemed to have little support in France, that Lutheran Germany displayed little interest in it, that Dutch writers hadn’t ìmuch time for it, although Huygens acknowledged its influence elsewhere, and (p.43) that in England it never gained a strong hold. [But what about support for geo-heliocentrism ? The Englishman Francis Bacon was a Capellan geo-heliocentrist, for example.]

Further down on p.43 she writes:

It is widely mentioned [N.B. she does not say supported] in printed books up to 1680, and there are scattered favourable references to it after that date] from 1700 onwards, however, it is normally mentioned only in order to refute it.”

~~The only country where Schofield states explicitly that there was strong support for the Tychonic system is Belgium.~~ Schofield does say (p.42) that support for Tycho was "markedly stronger" in Catholic countries, "notably Italy and Belgium", but the only one she discusses in any detail at all is Belgium. Surprisingly, she doesn't say ~~much~~ anything about the other Catholic ~~countries~~ country, ~~Italy and~~ Spain, where other sources indicate that support for the Tychonic system remained strong well into the 18th century. Again, while she also says that the Jesuits "presented a united front in favour of Tycho" throughout the 17th century (p.42), she then immediately goes on to say that after 1670 many of them disguised "but thinly their preference for Copernicus."

Neither does Schofield anywhere indicate that the semi-Tychonic system received any more support than Tycho's own. On pp.38-39 she writes that Nicholaus Muller "seems to have regarded it as of equal status with the Ptolemaic and Copernican", she lists 4 English supporters of it, and says it was "referred to frequently" (N.B. not "supported" or "favourably referred to") until around 1680, "and even (scathingly) in 1717".

The Pardies and Blanchinus quotations are useless as support for the claim that there was a general 17th-century conversion to geoheliocentrism, if for no other reason than that the secondary source they have been plucked from (viz. Schofield's article) flatly contradicts them. [FALSE. Schofield never says there was never a 17th century period of conversion to geoheliocentrism. So no contradiction there.]

But even if we ignore Schofield's opinions entirely, it ís not difficult to find quotations from other scientists in the latter half of the 17th-century which claim that heliocentrism was the commonly accepted system at that time (Nicolaus Mercator, for example, who wrote in his Institutiones Astronomicae of 1676: "And that is why nowadays most astronomers appreciate the Copernican system as by far the most probable of all.î) Such quotations cannot legitimately used on Wikipedia to support anything other than the fact that the persons so quoted have made them. Using them either as support for or opposition to a point of view (such as that there was a general 17th-century conversion to geoheliocentrism, for example) is explicity disallowed as original research by Wikipedia policy; unless, of course, a reliable secondary source cites them as evidence for that point of view, but, in this instance, that ís not the case. [But WikiPolicy aside, the relevant elementary logical point here is that neither Mercator’s nor anybody else’s testimony that the commonly accepted system in the latter half of the 17th century was heliocentrism entail there was never any geoheliocentric period, which is the point at issue Wilson is dealing with. They are perfectly compatible with geoheliocentrism having reigned from 1614 to 1644, for hypothetical example. ]

On the issue of Roemer subscribing to geoheliocentrism, Schofield appears to be mistaken. In an article (Copernicanism in Denmark and Norway) in The Reception of Copernicus's Heliocentric Theory (Jerzy Dobrzycki ed., p.141), the author,

Kristian Moesgaard, states that Roemer was a Copernican, and cites a letter from him to Leibniz in which he says he was convinced that the fixed stars displayed parallactic displacements, and that he might soon be able to publish his results on that subject. Given that Schofield cites no evidence whatever for her claim that Roemer subscribed to geoheliocentrism, I would tend to discount it until I have seen something more solid to support it. [But from when does Moesgaard say Roemer became a heliocentrist ? Or does she claim he always was one ? What did Herebow say on this issue, if anything ? But most specifically, note that it seems Moesgaard does not also relate whether Roemer did observationally establish parallactic displacment, and nor whether he published any such results., and thus whether he might have converted from geoheliocentrism as a result. Thus this letter seems to be indeterminate evidence of Roemer becoming a heliocentrist. But almost certainly he was never a Copernican, for he did not believe in the celestial spheres, a core tenet of Copernican astronomy.]

Finally, in the same Wilson and Taton volume that contains Schofield's article, Albert van Helden writes (p.103):

"... by the middle of the 17th century, the Copernican issue hardly raised an eyebrow in Protestant regions. The overwhelming majority of Protestant astronomers, or at least the creative Protestant astronomers, were now Copernicans." [But so what ? van Helden is as equivocally clear as mud here. What is a creative Protestant astronomer and who were they and how many of them, such that an overwhelming majority were heliocentrists by 1650 ? But it seems Helden is not prepared to claim that also an overwhelming majority of Protestant astronomers, both creative and non-creative, were heliocentrists, and even less that an overwhelming majority of astronomers were, including both non-Protestants and non-creatives. So van Helden is inconclusive on what the great majority view of astronomers was c1650. But of course most saliently to the point at issue here, again what the overwhelming majority of whatever population believed by 1650 does not entail the overwhelming majority had not previously become geoheliocentrists in the 17th century before then. ]

In view of all this, the weight of scholarly opinion would appear to me to be overwhelmingly against the assertions currently made in the article that there was a 17th-century conversion to geoheliocentrism. [A grossly invalid conclusion !]

I therefore plan to amend those assertions over the next few days.

—David Wilson (talk · cont) 15:25, 3 May 2009 (UTC)"

--Logicus (talk) 17:04, 8 July 2009 (UTC)

Logicus has clearly misunderstood my above response to his original remarks. By "general 17th century conversion to geoheliocentrism" I meant a conversion which persisted as the majority view until the end of the century, as Logicus was apparently claiming in his original comments. I apologise for not making that clearer. I agree that the sources cited do support the assertion that there was a conversion to geoheliocentrism in the early 17th century. But the article already acknowledges this in the following words:

"Galileo's observations of the phases of Venus therefore decisively disproved the Ptolemaic version of geocentrism. They did not, however provide conclusive evidence for Copernicus's theory, because they were equally compatible with various other theories, such as the geoheliocentric system of Tycho Brahe and the semi-Tychonic system proposed by Longomontanus, Nicolaus Reimers ("Ursus") and ~~Helisæus Röslin~~ David Origanus. Thus, in the early 17th century, following Galileo's telescopic discoveries, the majority of professional astronomers tended to favour one or other of these geoheliocentric alternatives, rather than the heliocentric system of Copernicus."

with an appropriate citation to Victor Thoren's article on Tycho Brahe in Vol 2A of the Wilson and Taton books.

I stand by my assertion that the cited references flaty contradict the claim that this conversion to geoheliocentrism lasted until the end of the 17th century. I am frankly gobsmacked that anyone could possibly read them as supporting that claim, and I would certainly strenuously object to its being added to the article. Since I never intended to deny that the majority of professional astronomers subscribed to geoheliocentrism during the early part of the 17th century, I will here only respond to Logicus's attempts to argue that this conversion lasted much longer than that.

Logicus wrote above:

[Quoting me] "While he doesn’t say precisely how rapidly Descartes' cosmology was accepted, he does say (on p.144) that by 1687, when Newton's Principia was published, it was "generally accepted".

[No, he does not say Descartes' cosmology nor heliocentrism were generally accepted by 1687 on p144, nor anywhere else. Rather he says: "Newton's Principia appeared in 1687. [Its title Mathematical Principles of Natural Philosophy] ...was a clear challenge to the generally accepted view of nature, as embodied in Descartes' systematic textbook Principles of Philosophy." But Descartes' 'view of nature' surely refers to his mechanist philosophy of nature here, rather than his cosmology and/or heliocentrism. Thus it was surely Descartes' mechanistic philosophy of nature he claims was accepted by 1687, rather than his cosmology and specifically heliocentric planetary model in particular. ]

No, not "surely" at all. The views enunciated in Descartes' Principles of Philosophy included his heliocentric cosmology. I see no reason to assume that when Hoskin wrote "the generally accepted view of nature, as embodied in Descartes' systematic textbook Principles of Philosophy" he intended to exclude Descarte's cosmology from what he was referring to. If he had so intended, he ought to have mentioned it specifically, especially in view of his earlier statement that: “From the publication of his Principles of Philosophy in 1644, it was increasingly accepted that the Sun was one of innumerable stars in homogeneous and boundless space, and that the planets circulated about the Sun ... “. In my opinion the apparent claim that Hoskin did not mean to include Descartes' heliocentric cosmology in his "view of nature" constitutes completely unjustified special pleading.

[Quoting me again] "The Pardies and Blanchinus quotations are useless as support for the claim that there was a general 17th-century conversion to geoheliocentrism, if for no other reason than that the secondary source they have been plucked from (viz. Schofield's article) flatly contradicts them.

[FALSE. Schofield never says there was never a 17th century period of conversion to geoheliocentrism. So no contradiction there.]

Poppycock. Read it again. The pronoun "them" at the end of my sentence clearly refers to "Pardies and Blanchinus quotations", so the claim here is that Schofield contradicted the assertions of Pardies and Blanchinus, not that she denied the occurrence of any conversion to geoheliocentrism. Here is what Schofield wrote about Pardies and Blanchinus (as already quoted by you above):

"In 1691 Ignace Gaston Pardies declared that the Tychonic [emphasis mine] was still the commonly accepted system, while Francesco Blanchinus reiterated this as late as 1728."

Note that Schofield here writes specifically "Tychonic", not "geoheliocentric". But later, on p.43, she writes:

"Thus this third system [i.e. the Tychonic] played a major part in the seventeenth century discussions of the cosmos. It is widely mentioned in books up to 1680, and there are scattered favourable references to it after that date [emphasis mine]: from 1700 onwards, however, it is normally mentioned only to refute it."

Would you please explain how a system for which there were only "scattered favourable references" after 1680 could have been the "commonly accepted system" in 1691, or how one which is "normally only mentioned to refute it" after 1700 could have been the "commonly accepted system" in 1728. Until you can do that satisfactorily, I shall continue to stand by my assertion that Schofield's article (specifically, her remarks on p.43) flatly contradicts the Pardies and Blanchinus claims, as reported by Schofield herself.

"[It should be noted re Wilson’s following reportage of Schofield comments on support for the Tychonic model that the issue here is rather support for geo-heliocentrism in general, which had 4 different models, namely Tychonic, semi-Tychonic, Capellan (Bacon) and Extended Capellan (Riccioli), and not just for the Tychonic model as Wilson invalidly presumes. ... ]"

No. Wilson made no such presumption. As I have already pointed out, Schofield says (on p. 39) much the same thing about the semi-Tychonic system as she later says about the Tychonic:

"The semi-Tychonic system is referred to frequently until around 1680, and even (scathingly) in 1717".

with the obvious implication that it was no longer referred to frequently after about 1680. I'm afraid I can't see how a system which was not frequently referred to after 1680 could have been a commonly accepted system after that date. This system also suffers from the problem that it was just as unacceptable to the Catholic Church as the heliocentric system, so it is unlikely to have enjoyed much support in countries where the Vatican's views on the matter remained prevalent.

That leaves the various systems in which some planets circle the Earth rather than the Sun. I will concede that Schofield's account nowhere explicity negates the possibility that support for one or more of those systems together might have more than made up for the dwindling support for the Tychonic and semi-Tychonic systems in the latter half of the 17th century. However, neither does she anywhere indicate that any of those systems were advocated by any more than the handful of supporters she mentions on page 38 of her article, and I know of no other reliable source which does so either. So if Logicus wants to try and take advantage of the wiggle room left by this loophole he will still need to find a reference which actually supports his position.

[Quoting me] " ... Kristian Moesgaard, states that Roemer was a Copernican, and cites a letter from him to Leibniz in which he says he was convinced that the fixed stars displayed parallactic displacements, and that he might soon be able to publish his results on that subject. Given that Schofield cites no evidence whatever for her claim that Roemer subscribed to geoheliocentrism, I would tend to discount it until I have seen something more solid to support it. [But from when does Moesgaard say Roemer became a heliocentrist ? Or does she claim he always was one ? ... "

I believe "Kristian" is a male name. Since the relevant pages of the reference are available on line at Google books, you can read them for yourself.

" ... What did Herebow say on this issue, if anything ? "

Herebow? Do you mean Horrebow? If so, see the reference already cited.

" ... But most specifically, note that it seems Moesgaard does not also relate whether Roemer did observationally establish parallactic displacment, and nor whether he published any such results ... "

Of course Roemer didn't observe stellar parallax. The closest star to Earth, Proxima Centauri, has a parallax of less than a second of arc. It simply wouldn't have been possible for Roemer to observe displacements that small with the instruments available to him. I've no idea why it "seems" to you that Moesgaard doesn't mention this (he does), or say whether Roemer published his results. In fact, Moesgaard says explicitly that Roemer didn't publish his results. Horrebow, however, later found an essay explaining the observations amongst Roemer's papers and published it in his Basis Astronomiae of 1735.

—David Wilson (talk · cont) 18:44, 9 July 2009 (UTC)

Logicus to Wilson: Resolutory edit proposal:

Thanks for your welcome clarification that you accept there was a period of geo-heliocentrism after the discovery of the phases of Venus. May I constructively suggest we shelve the thorny issue of just how long it lasted before the conversion to full heliocentrism? Thus I propose the following text:

'Galileo's telescopic observations of the gibbous and full phases of Venus therefore decisively disproved the total geocentrism of the Ptolemaic planetary model. Thus in the early 17th century as a result of his discovery the great majority of astronomers converted to one of the various geo-heliocentric planetary models<ref]Thoren (1989), p8, Hoskin (1999) p117. But Thoren is mistaken in claiming the phases of Mars also refuted Ptolemaic full geocentrism, which in fact predicts them.</ref], such as the Tychonic, Capellan and Extended Capellan models<ref]In the Capellan model only Mercury and Venus orbit the Sun, whlist in its extended version Mars also orbits the Sun, but the orbits of Jupiter and Saturn are centred on the Earth</ref], each either with or without a daily rotating Earth. These all had the virtue of explaining the phases of Venus without the vice of the refutation of full heliocentrism’s prediction of stellar parallax.'

This omits van Helden’s indecisive claim that by the mid 17th century the overwhelming majority of creative Protestant astronomers were Copernicans, since this is perfectly compatible with the great majority of astronomers still being geo-heliocentrists. I presume there were even fewer creative Protestant astronomers than there were leading Protestant astronomers.--Logicus (talk) 13:42, 11 July 2009 (UTC)

What appears to be overlooked here is the influence of the Church on the astronomers of that era. While a "silent" majority may or may not have begun a transition to heliocentrism during Galileo's time, they would have kept their mouths shut so as not to suffer his fate. And the vast majority of the population continued to believe that the Earth was the unmoving center of the Universe until more than 100 years after Galileo's discovery. Heliocentrism didn't begin to take firm hold on science until the 18th century. ^.`^) Paine Ellsworth ^diss`cuss (^^`. 11:42, 13 July 2009 (UTC)

(edit conflict)

I strongly disagree with a couple of aspects of Logicus's edit.

Logicus wrote:

"But Thoren is mistaken in claiming the phases of Mars also refuted Ptolemaic full geocentrism, which in fact predicts them."

As I have already pointed out above, this is incorrect. "Ptolemaic geocentrism"—at least, of the form that can be refuted by observations of the phases of Venus—predicts that the fraction of the disc of Mars covered by darkness, as viewed from the earth, should never be more than 4%. Thus, observation of a phase of Mars in which a clearly greater fraction than 4% of its disc were covered in darkness would refute that version of Ptolemaic geocentrism. Thoren's actual statement, " ... after telescopic discovery of the phases of Venus and Mars rendered Ptolemaic cosmology untenable ... " could therefore very well be sound. In any case, Wikipedia editors should not take it upon themselves to dispute statements made by apparently reliable sources unless they have something more to go on than their own possibly misconceived notions.

As far as I can tell, Thoren's article satisfies Wikipedia's criteria for reliable sources, and since Logicus's grounds for claiming he is mistaken are fallacious, I have removed the claim from the article.

Next:

"Galileo's telescopic observations of the gibbous and full phases of Venus therefore decisively disproved the total geocentrism of the Ptolemaic planetary model."

This is also incorrect. Ptolemy had no strong reason for preferring to place the orbits of Mercury and Venus on the near rather than the far side of the Sun, and he was well aware that he could just as easily have made the opposite choice. His physical model was therefore quite consistent with orbits of those planets which lay entirely on the far side of the Sun. In such an orbit Venus would also exhibit gibbous and full phases, and if those had been the only phases observed, it would have been a very strong indication that its orbit did in fact lie entirely on the far side of the Sun. To disprove the strict form of Ptolemy's geocentrism it was therefore necessary to observe the crescent as well as the gibbous or full phases. I have now amended the article accordingly.

—David Wilson (talk · cont) 14:02, 13 July 2009 (UTC)

In addition, when one studies geocentrism one finds no difference in the Platonic and the Ptolemaic geocentrism theories regarding the lack of motion of the Earth. Therefore, the "motionless" comment will be preserved, with an added qualification of "at least outwardly".

– ^.`^) Paine Ellsworth ^diss`cuss (^^`. 05:38, 18 July 2009 (UTC)

I am not completely satisfied with this explanation. Yes, the observed phases of Venus are contrary to the Ptolemy model. But it is not just because Venus is on a shell inside the Sun. It is also because Venus never gets too far from the Sun. Venus would be gibbous if Venus and the Sun were on opposite sides of the Earth, but that never happens. So perhaps that should be explained.

You also mentioned the possibility of modifying Ptolemy to put Venus outside the Sun. As you note, that also has problems. But if you are going to mention that possibility, then there is also the possibility that Venus alternated from being inside and outside the Sun. It seems to me that such a modification to Ptolemy would solve the Venus phase problem. I don't know whether anyone proposed this in the time of Galileo. But still I think that it overstates the case to say that gibbous phases of Venus made Ptolemy untenable. Roger (talk) 23:12, 13 July 2009 (UTC)

17th century geocentrism

Quoth the editor Logicus:

“

Have read Talk, Paine Ellsworth wrong, at that time likely most geocentrists believed in Earth's daily rotation, thus Earth not motionless

”

This is Logicus' logic as to why an edit war is justified. "Likely" is not good enough to counter WP:Preserve, is it? Let's see a source or two rather than to continue a senseless battle of editing! And I think we should keep in mind that the Catholic Church was "in charge" of science back then, and it is my assertion that the Church of that time both believed and practiced Ptolemaic geocentrism, and during the 17th century gradually came to accept the Tychonic system of Tycho, BOTH of which included a motionless Earth (and please note the cited reference sources in the "Tychonic system" article).
— ^.`^) Paine Ellsworth ^diss`cuss (^^`. 19:26, 23 July 2009 (UTC)