Wikipedia:Featured article candidates/Johannes Kepler


 * The following is an archived discussion of a featured article nomination. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article review. No further edits should be made to this page.

The article was promoted 20:59, 20 March 2007.

Johannes Kepler
Well-written article, rich of great relevant pictures, which is currently the article of the week on the Mathematics Portal. Tomer T 12:18, 8 March 2007 (UTC)
 * Support This article is well written and well cited. The images are used very well. I corrected a couple minor formatting errors (wikiling complete dates, adding &amp;nbsp; between the number and unit of a measurement) that you may want to double check. Very nice work. Jay32183 19:00, 8 March 2007 (UTC)
 * I'm retracting my support because it appears the experts on the subject do not feel the article is comprehensive yet. If I misunderstood those comments, please inform me. Jay32183 03:07, 14 March 2007 (UTC)
 * Restoring my support now that other Wikipedians' concerns have been addressed. Jay32183 22:24, 18 March 2007 (UTC)
 * Support &mdash; Yes it's a nice piece of work. There's a few minor fixes needed and quite a number of red links, but I do think this is FA quality. &mdash; RJH (talk) 20:54, 9 March 2007 (UTC)
 * Question The bit about his marriage, her father Jobst initially opposed a marriage despite Kepler's nobility. - Kepler was a noble? When did that happen? Sabine's Sunbird talk 21:22, 9 March 2007 (UTC)
 * Comments A few other niggles. Firstly the introduction's last paragraph seems to be about Kepler's personal theology and philosophy, a subject treated throghout the prose but not really all collected together to create one whole idea of who the man was. I'm sure I read somewhere that he felt that people should be allowed to believe whatever they wanted (or something to that effect)- quite a revolutionary idea for its time. Any chance of including that? Also the last section, named in Kepler's honour, is a laundry list, and would benefit from being turned to text and maybe incorporated with the oddly named The acceptance of Kepler's astronomy (surely impact of kepler's research would be better, or maybe Kepler's legacy) into one section abouyt the impact he had. I think the article is good overall (he's one of my personal heroes), but it doesn't quite punch hard enough on the areas that made the man so ahead of his time and unique. Sabine's Sunbird talk 04:03, 10 March 2007 (UTC)
 * I've done my best to address these issues. The expanded acceptance section is now called "Reception of Kepler's astronomy", and it is followed by a more broad ranging new section, "Kepler's historical and cultural legacy".  I think the "named in Kepler's honor" part is better left as a laundry list, although I've moved it to a more appropriate location (in the See also section).  The "ahead of his time" bit is really a complicated sort of thing, and probably an inherently philosophically-loaded issue as well, but I tried to address it as part of his cultural legacy.--ragesoss 08:42, 18 March 2007 (UTC)


 * Oppose The writing is good but I think the layout can be improved. As it stands this article is pretty much just one big biography section.  His life and work should really be separated. Cf. articles like Tycho Brahe and Galileo Galilei. --Idda 05:35, 10 March 2007 (UTC)
 * I Second Idda comments about the layout - 19:45, 10 March 2007 (UTC)
 * I agree. I'm slowly going through this article.  I removed the section heading 'Biography', which I think is one of the most useless of all headings.  I changed 'Childhood and education' to 'Early years' and you immediately get a better sense of what's going on in the article.  The content seems pretty good so far.  I'll report back later.-BillDeanCarter 17:03, 11 March 2007 (UTC)
 * I'm happy with the way you've broken it out of a "Biography" supersection. As for separating life from work, I'm am very strongly opposed to that.  The Galileo and Brahe articles are not examples that anyone should be following; I set about redoing the Kepler article with the express intent of avoiding the sort of thing that happened on Galileo, where it reads like a series of random essays on why Galileo is great.  Despite the official status, Galileo is a long way from the 2007 version of FA quality.--ragesoss 08:42, 18 March 2007 (UTC)


 * Support Very good article. The only improvement that I can think of is more evenly spacing the pictures.
 * Comment I think this is an excellent article and I applaud the editors for their efforts to describe Kepler within his own historical context rather than to write about him as a modern scientist. I think that the images are well-placed and that the writing is generally quite good. The article is almost complete. I have a list of little things that I feel can quickly be taken care of. This is a very high-quality article and I am almost ready to vote support.
 * I wonder about listing his "residence" as "Germany" and his nationality as "German" in the infobox. There was no German nation in the sixteenth and seventeenth centuries, just all those little principalities. Which one did Kepler live in most of the time and which one did he identify with? Even into the nineteenth century, for example, people thought of themselves as "Bavarian" rather than "German."
 * I've changed his residences to reflect the German and Austrian states in which he lived. As for nationality, I nixed it altogether; it's rather too complicated for an infobox.  Based on Caspar's biography, it seems that his religious identity was much more important than his political citizenship, but he was often eager to get back to Baden-Württemberg, where his family remained and where he had gone to school.--ragesoss 04:43, 14 March 2007 (UTC)
 * He is best known for his laws of planetary motion, based on his works Astronomia nova, Harmonice Mundi, and Epitome of Copernican Astronomy. - are the laws really based on the works? the wording seems a bit odd - how about "found in"?
 * "Based on" for the first two is more accurate, while "found in" might pass muster for Epitome; the phrase is meant to suggest that "Kepler's laws" are the product of later astronomers, since Kepler never actually laid them out together in that form. It takes some work to "find" Kepler's laws in Kepler's own work.--ragesoss 04:43, 14 March 2007 (UTC)
 * Ah, I see. Is there some way to make that clearer?
 * Fixed. Or at least, added an extra few words.--ragesoss 21:22, 15 March 2007 (UTC)
 * After Kepler, astronomers shifted their attention from orbs to orbits—paths that could be represented mathematically as an ellipse. - why are "orbs" and "orbits" italicized? also, the construction "could be represented" is odd - it indicates that perhaps they could also be represented as something else - I was under the impression that the ellipse bit was a huge breakthrough - orbits ARE ellipses - this sentence does not convey that
 * Orbs and orbits are italicized to emphasize that they are used here as (etymologically related but conceptually distinct) technical terms. "Orbits", in the most basic meaning, are paths through space, but not necessarily ellipses.  (In fact, they are generally not ellipses, except in non-relativistic two-body systems.)  Kepler and other later astronomers recognized that ellipses were a mathematically best-fit of orbits, not (necessarily) the platonic essence of orbits.--ragesoss 04:43, 14 March 2007 (UTC)
 * During his career Kepler was a mathematics teacher at a Graz seminary school (later the University of Graz, Austria) - is it really important to say in the lead that the school later became this university?
 * It will probably be of interest to some readers.--ragesoss 21:22, 15 March 2007 (UTC)
 * Kepler lived in an era when there was no clear distinction between astronomy and astrology, while there was a strong division between astronomy (a branch of mathematics within the liberal arts) and physics (a branch of the more prestigious discipline of philosophy); Kepler also incorporated religious arguments and reasoning into his work, motivated by the religious conviction that God had created the world according to an intelligible plan which was accessible through the natural light of reason. - awkward - perhaps break up the sentence? also, the "while" doesn't quite work - the connection is not clear between the two clauses
 * Fixed.--ragesoss 06:47, 14 March 2007 (UTC)
 * He was believed to have died in the war in the Netherlands. - what war?
 * Fixed: The Eighty Years' War.--ragesoss 04:43, 14 March 2007 (UTC)
 * Despite his ill health, he was precociously brilliant. - this is odd - what does health have to do with brilliance (e.g. Stephen Hawking)?
 * The idea was to contrast physical weakness with mental strength. However, I grant that it could be put better.  I think I've fixed it with a rephrase.--ragesoss 21:22, 15 March 2007 (UTC)
 * I'm a little nervous that all of the citations for the "Early life" section come from the same source. Do no other sources discuss Kepler's early life in any detail? Let me just pause and say something about citations here. I wonder a bit about your citations. For other articles that have been approved for FA, reviewers have been demanding many more than you have. For example, in the second paragraph of "Mysterium Cosmographicum" you reference "Barker and Goldstein, "Theological Foundations of Kepler's Astronomy," pp 88-113." That seems a little disingenuous. Also, you have whole paragraphs without any citations at all. I am simply trying to retain some consistency here.
 * Fixed. That overly broad Barker and Goldstein cite was a placeholder until I went back and figured out precisely where in the reference the info could be found.  The uncited paragraphs were mostly a matter of reapportioning citations that covered more than one paragraph.  Regarding his early life, there basically is only one main source that treats it in detail, plus a few others that are mostly derived from that source (I've added references for one of the others that contains a little bit of different analysis).  It's probably the least controversial part of his life, historically speaking, and Caspar is the only person who has really tackled Kepler's whole life, as opposed to a smaller part of his work.--ragesoss 06:47, 14 March 2007 (UTC)
 * Fair enough on the Caspar.
 * He was introduced to astronomy/astrology at an early age - pick a word or rephrase - that's just ugly
 * Fixed.--ragesoss 04:43, 14 March 2007 (UTC)
 * earned a reputation as a skillful astrologer - what does this mean? is it explained by the following sentences? if so, that is not clear
 * It means he wrote horoscopes for other students and did other astrology work, and he developed a reputation for being good at it. It is not explained in the following sentences; it merits mention, but probably isn't significant enough for an extended discussion.--ragesoss 04:43, 14 March 2007 (UTC)
 * Perhaps a sentence or phrase?
 * Fixed.--ragesoss 21:22, 15 March 2007 (UTC)
 * Kepler's first major astronomical work, Mysterium Cosmographicum (The Sacred Mystery of the Cosmos), was also the first published defense of the Copernican system. - I get what you're saying with the "also" but it is awkward - try to reword
 * Fixed'. Removed "also".--ragesoss 04:43, 14 March 2007 (UTC)
 * her father Jobst initially opposed a marriage despite Kepler's nobility - earlier you said his father was a mercernary and his mother was an inn-keeper's daughter - please clarify
 * Fixed. His grandfather Sebald Kepler was "Lord Mayor", a position of nobility.  Essentially, Kepler had a title but none of the other blessings of nobility (e.g., money).--ragesoss 04:43, 14 March 2007 (UTC)
 * However, church officials pressured the Müllers to honor their agreement - does anyone know why?
 * A combination of things: church/school officials had had a hand in setting up the match, and Kepler had friends among the church officials. There was some sort of formal betrothal that the church either had to enforce or dissolve, and it seems that the outcome was up in the air for a little while.  Caspar is the main source for Kepler's personal life, and he is doesn't give much more detail than that.--ragesoss 04:43, 14 March 2007 (UTC)
 * Perhaps you could add in a sentence to this effect.
 * Fixed. I added a phrase indicating that the church officials helped set up the match.  Any more detailed explanation will be too convoluted to be worth it.--ragesoss 21:22, 15 March 2007 (UTC)
 * Agreed. Awadewit 10:33, 18 March 2007 (UTC)
 * Could you add stub pages for the red-links or de-link them?
 * I had planned to do that before I nominated the article for FA, but since the gun has been jumped... I'm working on it.--ragesoss 04:43, 14 March 2007 (UTC)
 * Done.--ragesoss 21:15, 18 March 2007 (UTC)
 * Through most of 1601, he was supported directly by Tycho, analyzing planetary observations and writing a tract against Tycho's (now deceased) rival Ursus. - this is awkward - was he supported because he was doing these things?
 * Fixed. I added "who assigned him to" after "Tycho".--ragesoss 04:43, 14 March 2007 (UTC)
 * In addition to horoscopes for allies and foreign leaders, the emperor sought Kepler's advice in times of political trouble—though Kepler's recommendations were based more on common sense than the stars. - dash doesn't work (by the way, certainly a statement such as this needs to have a citation!)
 * Changed. I won't say "fixed", because I think it was a valid use of the long dash.  On the other hand, it's not a big deal one way or the other, and you're the ABD Englishist.--ragesoss 21:22, 15 March 2007 (UTC)
 * further undermining the doctrine of the immutability of the heavens - you have to put this in context for the reader.
 * Fixed, with a parenthetical description of the concept. A slightly shady alternative would be to link immutability of the heavens and redirect it to celestial spheres.--ragesoss 21:15, 18 March 2007 (UTC)
 * In an appendix, Kepler also discussed the recent chronology work of Laurentius Suslyga; he calculated that, if Suslyga was correct that accepted timelines were four years behind, then the Star of Bethlehem—analogous to the present new star—would have coincided with the first great conjunction of the earlier 800-year cycle. - not clear why this is significant
 * If that astrological event (associated with the birth of Christ) was precisely marked by the appearance of the Star of Bethlehem, it made the new star that much more important; it would set a precedent of associating a new star with the beginning of the fiery trigon (along with all the other things it was supposed to mean). It's not especially important, it was just part of Kepler's argument about the significance of the new star (and, hence, his work on it) and illustrates the breadth of Kepler's scholarly interest.--ragesoss 21:22, 15 March 2007 (UTC)
 * Ah. Perhaps you could add a phrase at the beginning of the sentence to that effect: "Kepler's scholarly interests were widespread; he also.." or some such thing.
 * That would make it seem more like a digression. The main reason that information is there is that it is part of Kepler's case for the significance and interpretation of the supernova.--ragesoss 21:31, 18 March 2007 (UTC)
 * Perhaps you could make that explicitly clear? Awadewit 21:49, 18 March 2007 (UTC)
 * Kepler calculated and recalculated various approximations of Mars' orbit using an equant - what is an "equant"?
 * Fixed. I didn't quite define it, but I linked it and added a parenthetical note that gives sufficient context.--ragesoss 21:22, 15 March 2007 (UTC)
 * I like it.
 * in early 1605 he at last hit upon the idea of an ellipse, which he had previously assumed to be too simple a solution for earlier astronomers to have overlooked - I thought that he also thought it couldn't be possible because God would not use an imperfect shape?
 * Sort of. Just before using the ellipse, he had been trying a slew of more complicated ovoids, so he had already given up the idea that God would only use circles (and even then, it's not clear that he ever thought that exactly; his Mysterium model included a parameter, the thickness of the spherical shells within which planets moved or were embedded, that allowed the same sorts of deviations from circular paths that all contemporary astronomers used).  I think it was more that he expanded his notion of perfect shapes, but it's tough to pinpoint changes in his theological reasoning.--ragesoss 21:22, 15 March 2007 (UTC)
 * I feel betrayed by Carl Sagan. :) Awadewit 10:33, 18 March 2007 (UTC)
 * in the years following the completion of Astronomia Nova, most of Kepler's research was focused on preparations for the Rudolphine Tables and a comprehensive set of ephemerides based on the table (though neither would be completed for many years). - briefly define "ephemerides" so that the reader doesn't have to click (how many readers will, anyway?)
 * Fixed. (All the ones who more than a brief and sketchy parenthetical definition.)--ragesoss 21:22, 15 March 2007 (UTC)
 * (By the way, I assume you meant "don't want more than..") and teaching is good. Draw them in with your compelling story of Kepler, and maybe they will become a historian or a scientist or donate money to their local science museum. One can only hope. Awadewit 10:33, 18 March 2007 (UTC)
 * In his first years there, he enjoyed financial security and religious freedom relative to Prague - awkward - perhaps "relative to his time in Prague"?
 * Fixed. "relative to his life in Prague".--ragesoss 21:22, 15 March 2007 (UTC)
 * the fifth of eleven matches he had considered following Barbara's death - confusing - he considered eleven women and then went back to the fifth one?
 * Fixed. Yes.  I reworked this section, adding a bit of detail and clarifying this issue.--ragesoss 21:22, 15 March 2007 (UTC)
 * Three more survived: Cordula in 1621; Fridmar in 1623; and Hildebert in 1625. - they survived into these years? they were born in these years? very confusing
 * Fixed.--ragesoss 21:22, 15 March 2007 (UTC)
 * She was released in October 1621, thanks in part to the extensive legal defense drawn up by Kepler; the accusers had no stronger evidence than rumors and (a distorted, second-hand version of) Kepler's Somnium story—in which a woman mixes potions and enlists the aid of a demon. - awkwardly worded
 * Fixed, I think.--ragesoss 21:22, 15 March 2007 (UTC)
 * Many people were condemned of witchcraft on much thinner evidence than this, though, so to say "the accusers had no stronger evidence than..." is rather misleading in my opinion, but if that is how the biographers present it, so be it. During the Salem witch trials, women were condemned on the testimony of a single "witness." A book (however distorted) is a major step up in a witchcraft trial. This is just something to think about. It would seem to me that the reason Kepler took his mother's defense so seriously was because she was in real danger. Am I wrong about this? Awadewit 10:33, 18 March 2007 (UTC)
 * Your interpretation here is pretty much right on. The main thing working in her favor, which maybe isn't spelled out clearly enough but that I tried to get across, is that she had the intelligent and (perhaps more important) respectable Johannes Kepler running her legal defense.  From Kepler's perspective it was thin evidence, but obviously it was a serious danger (and understood as such by the Keplers), as it ended in territio verbalis.  This actually isn't treated with very much sophistication in any of the sources I've seen, though.--ragesoss 20:41, 18 March 2007 (UTC)

Nice work - I learned a lot. Awadewit 12:30, 12 March 2007 (UTC)
 * However, Katharina was subjected to territio verbalis, a graphic description of the torture awaiting her as a witch, in a final attempt to make her confess, and she died soon after. - you imply that she died because of this - is that supportable?
 * Fixed. It was not meant to imply that, so I just removed the mention of her death, which is not very relevent.--ragesoss 21:22, 15 March 2007 (UTC)
 * I think that the "acceptance of Kepler" needs to be expanded. It needs to include information on when Kepler's laws were fully accepted - when his planetary laws were fully proved.
 * Expanded. Now it goes up to Newton, plus a section on "Kepler's historical and cultural legacy" after that.--ragesoss 08:45, 18 March 2007 (UTC)
 * Why do you mention Rene Descartes as one of the people who ignored Kepler? He is known as a mathematician but not a scientist; in fact, he is much more famous as a philosopher. Why is it notable that he ignored Kepler? He was not studying what Kepler was studying like Galileo was. You might want to make some sort of argument about that.
 * Actually, Descartes was doing the same sorts of things as Galileo in particular (though without experiments); Descartes created a rival system of physics (which Newton's work is partially a response to).  He created a widely circulated system of cosmology, and was known primarily as a natural philosopher in his own time and in the 18th century.  For quite a while after Newton, Descartes' physics reigned in France; that is the main context, for example, of Voltaire and du Chatelet's adaptations and translations of Newton in the mid-1700s, well after Newton's physics (if not mathematics) was accepted in the English- and German-speaking worlds.  See also Pierre Louis Maupertuis (second paragraph of the biography section) for another aspect of the Newton-Descartes issue.  I don't think the Kepler article is really the place to go into this, although the Descartes article is rather awful when it comes to his natural philosophy.--ragesoss 21:01, 18 March 2007 (UTC)
 * Didn't know that - much more familiar with his philosophy (mind-body dualism, etc.) Awadewit 21:49, 18 March 2007 (UTC)
 * In the "Writings" section, I don't think there is a need to link years, that seems to be generally frowned upon.
 * Fixed.--ragesoss 21:22, 15 March 2007 (UTC)
 * I am personally not a fan of culture sections like "Kepler in Fiction." What do they really add?
 * Nothing. The single entry is part of the new Legacy section.--ragesoss 08:42, 18 March 2007 (UTC)
 * I would also prefer the "bibliography" and the "further reading" to be combined so that if someone is coming to this page primarily for citations, they can easily find them all.
 * Done.--ragesoss 08:42, 18 March 2007 (UTC)
 * Comments. I think this nomination is a little premature.  SteveMcCluskey and I have been putting in a lot of work for this article, which has been on hiatus lately as real life intervened for us.  But I think there is still some work we want to do, especially dealing the reception of his work in a broader context and with his legacy for the history and philosophy of science, which I hope to get to in the near future.  Awadewit, thank you very much for your concrete suggestions, which will be helpful.  --ragesoss 02:54, 14 March 2007 (UTC)


 * More comments Some more tiny things and then I will be ready to enthusiastically support.
 * I love your use of eponymous, but I'm not sure that that is a very commonly used word. What do you think about linking it to wiktionary?
 * Fixed. No need for wiktionary, we have Wikipedia article eponym.--ragesoss 20:41, 18 March 2007 (UTC)
 * I think "precociously brilliant" sounds a little redundant.
 * Fixed.--ragesoss 20:41, 18 March 2007 (UTC)
 * Also in that year, Barbara Kepler contracted Hungarian spotted fever, then began having epileptic seizures. - one does not have epileptic seizures unless one has epilepsy - one can have seizures, though, with a lot of different diseases - I am guessing that Barbara had the seizures because of the fever (high fevers bring on seizures) and not because she had epilepsy? - a small but crucial distinction - if she had epilepsy, that should be made clear (the sentence currently connects the seizures to the fever)
 * Fixed. The Connor source says "epileptic seizures", but I think he was just being sloppy; I removed "epileptic".--ragesoss 20:41, 18 March 2007 (UTC)
 * I noticed almost all of your citations contain page ranges rather than specific pages. That is fair enough, I suppose (I may start doing that myself to save time), but when you have a quotation in the text, you should immediately give the source for that. Here are two I found:
 * At age five, he observed the Comet of 1577, writing that he "was taken by [his] mother to a high place to look at it."
 * Fixed.--ragesoss 20:41, 18 March 2007 (UTC)
 * He eventually returned to Reuttinger (the fifth match) who, he wrote, "won me over with love, humble loyalty, economy of household, diligence, and the love she gave the stepchildren."
 * Fixed.--ragesoss 20:41, 18 March 2007 (UTC)


 * This culminated in Isaac Newton's Principia Mathematica (1687), in which Newton derived Kepler's laws of planetary motion from his force-based theory of universal gravitation. - in this sentence "his" is ambiguous; it looks like it is referring back to Kepler, meaning "Kepler's force-based theory of universal gravitation"
 * Fixed, by replacing "his" with "a".--ragesoss 20:41, 18 March 2007 (UTC)
 * William Whewell, in his influential History of the Inductive Sciences of 1837, found Kepler to be the archetype of the inductive scientific genius, and in his Philosophy of the Inductive Sciences of 1840, an exemplar of the most advanced forms of scientific method. - awkward, particularly last part - how can a person be an example of the "most advanced form of the scientific method"?
 * Fixed. Put a semi-colon in the middle, rephrased from "example" to "embodiment".--ragesoss 20:41, 18 March 2007 (UTC)
 * examples of incommensurability, analogical reasoning, falsification, and many other philosophical concepts have been found in Kepler's life - do you mean his "work"?
 * Fixed. Yes.--ragesoss 20:41, 18 March 2007 (UTC)
 * It is traditional to list bibliographies alphabetically by the author's or editor's last name. I am wondering if there was some error in a wikipedia template that caused this to happen because the editors' summary of the historiography of Kepler leads me to believe they already know this. :)
 * Are you pointing out a problem, being witty, or both? In any case, I don't follow. --ragesoss 20:41, 18 March 2007 (UTC)
 * "Witty" is perhaps too kind. The bibliography should be alphabatized by the author's last name, no? Not all of your sources are listed that way. Awadewit 20:53, 18 March 2007 (UTC)
 * I think I fixed it. I found one outright error and one (the Great Books of the Western World one) that was previously listed at the end, which I moved to join the rest of the Kepler stuff (since that's the only author from it that is relevant to the article).
 * I mean not "John Lear" but "Lear, John." Awadewit 21:42, 18 March 2007 (UTC)
 * Ah. I see.  Fixed.--ragesoss 21:54, 18 March 2007 (UTC)

I thought that the "cultural legacy" section was excellent. Never have I seen pop culture references worked in so seamlessly. Awadewit 10:33, 18 March 2007 (UTC)

Support This article is well-written (one of the few that has really "compelling prose"), well-sourced and comprehensive. I am particularly impressed with its ability to integrate information into a cohesive article. My only remaining quibble is the bibliography (see above). This article was a pleasure to review. Awadewit 21:49, 18 March 2007 (UTC)


 * Support. Thank you very much for all the insightful feedback.  I'm finally ready to put my own support behind this article.--ragesoss 21:54, 18 March 2007 (UTC)


 * Support. Thanks to Ragesoss for bringing this article from controversy to featured status.--SteveMcCluskey 01:37, 19 March 2007 (UTC)
 * The above discussion is preserved as an archive. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article review. No further edits should be made to this page.