The Copernican Revolution: Planetary Astronomy in the Development of Western Thought

by Thomas S. Kuhn

For scientist and layman alike this book provides vivid evidence that the Copernican Revolution has by no means lost its significance today. Few episodes in the development of scientific theory show so clearly how the solution to a highly technical problem can alter our basic thought processes and attitudes. Understanding the processes which underlay the Revolution gives us a perspective, in this scientific age, from which to evaluate our own beliefs more intelligently. With a constant keen awareness of the inseparable mixture of its technical, philosophical, and humanistic elements, Mr. Kuhn displays the full scope of the Copernican Revolution as simultaneously an episode in the internal development of astronomy, a critical turning point in the evolution of scientific thought, and a crisis in Western man's concept of his relation to the universe and to God. The book begins with a description of the first scientific cosmology developed by the Greeks. Mr. Kuhn thus prepares the way for a continuing analysis of the relation between theory and observation and belief. He describes the many functions--astronomical, scientific, and nonscientific--of the Greek concept of the universe, concentrating especially on the religious implications. He then treats the intellectual, social, and economic developments which nurtured Copernicus' break with traditional astronomy. Although many of these developments, including scholastic criticism of Aristotle's theory of motion and the Renaissance revival of Neoplatonism, lie entirely outside of astronomy, they increased the flexibility of the astronomer's imagination. That new flexibility is apparent in the work of Copernicus, whose DE REVOLUTIONIBUS ORBIUM CAELESTIUM is discussed in detail both for its own significance and as a representative scientific innovation. With a final analysis of Copernicus' life work--its reception and its contribution to a new scientific concept of the universe--Mr. Kuhn illuminates both the researches that finally made the heliocentric arrangement work, and the achievements in physics and metaphysics that made the planetary earth an integral part of Newtonian science. These are the developments that once again provided man with a coherent and self-consistent conception of the universe and of his own place in it. This is a book for any reader interested in the evolution of ideas and, in particular, in the curious interplay of hypothesis and experiment which is the essence of modern science. Says James Bryant Conant in his "Professor Kuhn's handling of the subject merits attention, for... he points the way to the road which must be followed if science is to be assimilated into the culture of our times."

Genres: Science, History, Philosophy, Nonfiction, History Of Science, Astronomy, Physics

318 pages, Paperback

First published January 1, 1957

About the author

American historian and philosopher of science, a leading contributor to the change of focus in the philosophy and sociology of science in the 1960s. Thomas Samuel Kuhn was born in Cincinnati, Ohio. He received a doctorate in theoretical physics from Harvard University in 1949. But he later shifted his interest to the history and philosophy of science, which he taught at Harvard, the University of California at Berkeley, Princeton University, and Massachusetts Institute of Technology (MIT).

In 1962, Kuhn published The Structure of Scientific Revolutions, which depicted the development of the basic natural sciences in an innovative way. According to Kuhn, the sciences do not uniformly progress strictly by scientific method. Rather, there are two fundamentally different phases of scientific development in the sciences. In the first phase, scientists work within a paradigm (set of accepted beliefs). When the foundation of the paradigm weakens and new theories and scientific methods begin to replace it, the next phase of scientific discovery takes place. Kuhn believes that scientific progress—that is, progress from one paradigm to another—has no logical reasoning. Kuhn's theory has triggered widespread, controversial discussion across many scientific disciplines.

Reviews

[Roy Lotz · Rating 5 out of 5]

There are few phrases more annoying or more effective than “I told you so.”

This is my second encounter with Thomas Kuhn, and again I emerge deeply impressed. To do justice to an event so multifaceted as the Copernican Revolution a scholar must have a flexible mind; and Kuhn is fully equal to the task. He moves seamlessly from scientific data, to philosophical analysis, to historical context, and then back again. The result is a book that serves as an admirable introduction to the basics of astronomy and a thorough overview of the Copernican Revolution, while raising intriguing questions about the nature of scientific progress.

Kuhn first makes an essential point: that the conceptual schemes of science serve both a logical and a psychological function. Their logical function is to economically organize the data (in this case, the position and movement of heavenly objects); their psychological function is to make people feel at home in the universe. Belief is only necessary for this second function. A scientist can use a conceptual scheme perfectly well without believing that it represents how the universe ‘truly is’; but people have an obvious and, apparently, near-universal need to understand their place in, and relation to, the cosmos. Thus, scientists throughout history have insisted on the truth of their systems, despite the history science being littered with the refuse of abandoned theories (to use Kuhn’s expression). Even if this belief cannot be justified philosophically, however, it does provide a powerful emotional impetus to scientific activity.

Another question Kuhn raises is when and why scientists decide that an old paradigm is unsustainable and a new one is required. For centuries astronomers in the Muslim and Western worlds worked within the basic approach laid down by Ptolemy, hoping that small adjustments could finally remove the slight errors inherent in the system. During this time, the flexibility of the Ptolemaic approach—allowing for fine-tuning in deferents, equants, and epicycles—was seen as one of its strengths. Besides, the Ptolemaic astronomy was fully integrated within the wider Aristotelian science of the age; and this science blended perfectly with common everyday notions. The fact that the Ptolemaic science broke down is attributable as much, or more, to factors external to the science as to those internal to it. Specifically, with the Renaissance came the rediscovery of Neoplatonism, with its emphasis on mathematical harmonies—something absent from Aristotelianism—as well as its strain of sun-worship.

Copernicus was one of those affected by the new current of Neoplatonism; and it is this, Kuhn argues, that ultimately made him dissatisfied with the Ptolemaic system and apt to place the sun at the center of his system. We often hear of science progressing as a result of new experiments and empirical discoveries; but no such novel observation played a role in Copernicus’s innovation. Rather, the source of Copernicus’s rejection of an earth-centered universe was its inability to explain why the planets’ orbits are related to the sun’s. His system answered that question. But this was only an aesthetic improvement. It did not lead to more accurate predictions—the essential task of astronomy—and, indeed, it did not even lead to more efficient calculations. The oft-reproduced image of the Copernican universe, consisting of seven concentric circles, is a simplification; his actual system used dozens of circles and was cumbersome and difficult to use.

But the most puzzling feature of Copernicus’s innovation is that it achieves qualitative simplification at the expense of rendering it completely incompatible with the wider worldview. Aristotelian physics cannot explain why a person would not fly off of a moving earth. And, indeed, the entire cosmological picture, such as that painted so convincingly by Dante, ceases to make sense in a Copernican universe. For centuries people had understood the earth as a midpoint between the fires of hell and the perfect heavens above. Now, hell was only metaphorically “below” and heaven only metaphorically “above.” Besides that, the universe had to be expanded to mystifying proportions; the earth became only a small and unimportant speck in an unimaginably vast space. Strangely, however, Copernicus seemed blind to most of these consequences of his innovation. A specialist concerned only with creating a harmonious system, his attempt to render it physically plausible or theologically palatable is, at best, half-hearted.

This leads to the irony that one of the greatest intellectual revolutions in history started with a man concerned with technical minutiae inaccessible to the vast majority of the public, who had access to no fundamentally new data, whose system was neither more accurate nor more efficient than its predecessor, and whose main concern was qualitative harmoniousness. Copernicus was no radical and had no notion of upsetting the established authority; he himself would likely have been appalled at the Newtonian universe that was the end result of this process.

Yet this simple innovation, once proposed, had ripple effects. Though the earth’s motion was near universally rejected as a fact, its use in a serious astronomical work kept it alive as an option. And this new option could not be laughed away when, in the next generation under Tycho Brahe, better observations and novel phenomena upset the Ptolemaic world order. The heavens could no longer be seen as perfect and unchanging when Brahe proved that supernovae and comets do not exhibit a parallax (as in, they do not to change location when the observer moves), and thus could not be atmospheric phenomena. Further, Brahe’s unprecedentedly accurate observations of the planets were incompatible with any Ptolemaic system. This seems to be one of many cases in the history of science when novel observations followed, rather than preceded, a theoretical innovation.

Granted, this incongruence led Brahe to propose his own earth-centered system, the Tychonic, rather than adopt a sun-centered universe. But this new system used Copernican mathematics, and embodied the Copernican harmonies. In any case it is hard to see how the Tychonic system could ever have been anything but a stopgap, since the jump from Ptolemy to Brahe was scarcely easier than the jump from Ptolemy to Copernicus. Besides, it struck many as dynamically implausible that everything in the universe would orbit the sun except the earth and the moon.

Kepler and Galileo were among those unconvinced by the Tychonic system. The two very different men were both of an independent turn of mind, and their work finally made the Copernican universe unequivocally superior. Kepler particularly made the decisive step with his three laws: that planets orbit in ellipses with the sun at a foci, that they sweep out equal areas in equal times, and that they orbit the sun in a ratio of the 3/2 power (the orbital axis to the orbital time). But in Kepler we find further ironies. Far from the dispassionate lover of truth, Kepler was a Neoplatonic mystic, bursting with occult hypotheses. Many parts of his work strike the modern reader as scarcely more rational than the ravings of a conspiracy theorist. Yet the hard core of Kepler’s astronomical work lifted Copernicanism into a league of its own for accuracy of prediction and efficiency of calculation. If the orbits of the planets were related to the sun in such simple, elegant ways, it was difficult to see how earth could be at the center of it all.

This is my best attempt at summarizing the most salient points of the book. But of course there is far more in here, most of it worthwhile. I particularly enjoyed Kuhn’s chapter on the oft-ignored medieval research into physics, such as the impetus theory in the work of Nicole Oresme. The only weak point of the book was the rather brief epilogue to Copernicus. In particular, I would have appreciated an entire chapter devoted to Newton, since it was his Principia that was, in Kuhn’s phrase, the “capstone” of the revolution. But on the whole I think this is a superlative book, serious yet accessible, informative while brief. Kuhn captures the reality of scientific progress, which is far less neat that we may like to believe. Most striking is how a revolution which was guided by many extra-logical considerations—the Neoplatonic belief in celestial harmonies, the desire for mathematical elegance, the weakening of the religious worldview, the need to feel at home in the universe—fueled a process which, taken as a whole, resulted in a science definitively better than the Ptolemaic system it replaced.

Kuhn makes no mistake about this. Here is what the reputed relativist has to say:

The last two and one-half centuries have proved that the conception of the universe which emerged from the Revolution was a far more powerful intellectual tool than the universe of Aristotle and Ptolemy. The scientific cosmology evolved by seventeenth-century scientists and the concepts of space, force, and matter that underlay it, accounted for both celestial and terrestrial motions with a precision undreamed of in antiquity. In addition, they guided many novel and immensely fruitful research programs, disclosing a host of previously unsuspected natural phenomena and revealing order in fields of experience that had been intractable to men governed by the ancient world view.

[Ted · Rating 5 out of 5]

Probably a 4.5, made up of a 5 when I first read it (almost 40 years ago) and a 4 when I reread it much more recently. I don't think the book changed, but there is evidence that I did.

Kuhn is one of the thinkers of the History and Philosophy of Science that has written very famous books in both branches of that discipline. This is his contribution to the historical branch, while The Structure of Scientific Revolutions is his very influential (and thus also controversial) contribution to the philosophical branch.

This is a book definitely worth reading from the "history of ideas" shelf of your mental library.


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[Graeme Rodaughan · Rating 5 out of 5]

An extremely accessible book on the Copernican revolution.

From Wiki: https://en.wikipedia.org/wiki/Coperni...

"Copernicus removed Earth from the center of the universe, set the heavenly bodies in rotation around the Sun, and introduced Earth's daily rotation on its axis."

And, that certainly set the cat amongst the pigeons. I still think that many in our modern civilization hanker for a world in which humanity, and each one of us is - at the center of the universe. (The lust for significance is strong within our modern culture.)

This paradigm shift was only equaled by Darwin and Einstein.

This book has had a profound impact on my own thinking about how any culture evolves (or stagnates) over time. This book is indispensable if you want to understand human culture and society.

[Katie · Rating 5 out of 5]

Oh man, this book is wonderful. I'm a bit biased: it manages to touch on pretty much everything that I like and weave them together in a way that's fascinating and compelling. While I'm not a scientist myself - a pretty intense aversion to math when I was in high school turned me away from that - I absolutely love science and think it's fascinating, so anytime I come across a history of science book I always feel like I'm in a for a bit of a treat. Unfortunately, it can occasionally be difficult to find books that manage to be both good science books and good history books. This one does.

Kuhn is probably most famous for The Structure of Scientific Revolutions, a book I may have to go back and look at again. I remember reading it and thinking that he had a really good idea, but squandered a bit of it by making his work much more impenetrable than it needed to be. Now I'm thinking that may have been on me, though, because this work is beautifully written and persistently clear in its narrative. Kuhn takes a look at the Copernican Revolution and asks two main questions: why did it take so long to occur? And why did it ever occur at all? Kuhn provides an answer that I found really convincing and compelling, drawing on not only the traditional scientific developments leading up the 15th century but also the wider cultural changes that were occurring, from the Protestant Reformation to the resurgence of Neoplatonism.

Also, as if he needed to win my heart over even more, Kuhn manages to offer a fair and sensitive assessment of medieval science and its role leading up to Copernicus. Yay!

[Andrew]

Whereas The Structure of Scientific Revolutions is a book of bold claims about the very nature of science itself, The Copernican Revolution is a much humbler effort-- the account of one revolution, and how it came to pass, and how the ideas of Copernicus, Tycho Brahe, Kepler, Galileo, and Newton all intersected in early modern Europe. While his follow-up to The Copernican Revolution attempted to rephrase philosophical terms, this is a more of a straightforward piece of scientific nonfiction. Great storytelling, great history, interesting analysis of the role metaphor took (and continues to take) in the scientific endeavor.

[Xander · Rating 4 out of 5]

This book is by far the most accessible and enlightening book I have ever read on this subject. It is hard to pin this book down on one topic though. It is an introduction to astronomy (ancient and modern), it is a story about the building and destruction of world views, it is an informative account of the scientific revolution and its implications for mankind. And to top it off: it is written in a very clear and concise style.

Read 265 pages and you're fully informed. Not much else to say about it.

[Barbaros Sulakoglu · Rating 5 out of 5]

Copernicus ile başlayan Newton'la sonuçlanan ve inançtan bilime, felsefeden politikaya bir çok disiplini etkileyen, insanlığı bugüne taşıyan muazzam bir devrimi okudum. . .

[the_deepest_black]

Kopalnia wiedzy, niemniej nie zadowala do końca podział osiągnięć starożytnej astronomii między Eudoksosa z Knidos, Apoloniusza z Pergi i Klaudiusza Ptolemeusza.

### CYTATY ###

Grecja / początek.
Bardzo elegancja koncepcja dwusferycznego wszechświata. "Począwszy od IV stulecia [p.n.e.] większość greckich astronomów i filozofów była zdania, że Ziemia jest niewielką kulą, nieruchomo zawieszoną w geometrycznym centrum o wiele większej obracającej się sfery, unoszącej gwiazdy. Słońce porusza się w pustej przestrzeni między Ziemią a sferą gwiazd. Poza obszarem tej zewnętrznej sfery nie istnieje nic - ani przestrzeń, ani materia" (47-48).

Argument oparty na symetrii. "Tak np. centralne położenie Ziemi utrzymywać ją miało nieruchomo w środku kulistego wszechświata. W jakim bowiem kierunku spadać może ciało znajdujące się w centrum kuli? Względem tego punktu nie istnieje kierunek 'w dół'; każdy kierunek prowadzi w takim samym stopniu 'do góry'. Toteż wiecznie nieruchoma Ziemia musi znajdować się w centrum obracającego się wokół niej wszechświata" (50).

"Już w V stuleciu p.n.e. greccy atomiści Leukipp[os] i Demokryt przedstawiali wszechświat jako nieskończoną pustą przestrzeń, w której we wszystkich kierunkach porusza się nieskończona ilość maleńskich i niepodzielnych cząstek - atomów. W tym wszechświecie Ziemia miała być tylko jedną z wielu zasadniczo do siebie podobnych ciał niebieskich, powstałych wskutek przypadkowego połączenia się atomów. Nie była szczególnie wyróżnionym ciałem niebieskim, ani nie znajdowała się w centrum wszechświata, ani też nie była nieruchoma" (64).

"Pod koniec IV w. p.n.e pusty świat dwusferyczny został wypełniony. Później ulec miał przepełnieniu" (74). Na podstawie rozwiniętego dwusferycznego modelu można było wytłumaczyć, a niekiedy nawet przewidzieć niektóre zjawiska, np. zaćmienia, a nawet określić niektóre wymiary astronomiczne (77).

Pitagorejski Ołtarz Zeusa.

"Sto lat później Heraklejdes z Pontu (IV w. p.n.e.) [Kopernik twierdził, że również Filolaos] sugerował, że dziennego obrotu dokonuje Ziemia, nie zaś ogromna sfera gwiezdna, i że skutkiem jej obrotu jest pozorny ruch niebios. Zburzył on również symetrię dwusferycznego modelu wszechświata, twierdząc, że planety Merkury i Wenus obracają się po okręgach wokół ruchomego Słońca, a nie po orbitach kołowych wokół centralnie położonej Ziemi" (64).

Eudoksos
"[...] wadę, która spowodowała, że już w starożytności szybko z niej zrezygnowano. Wobec tego, że teoria Eudoksosa umieszcza planety na sferze współśrodkowej z Ziemią, odległość między Ziemią a planetą powinna pozostawać stała. W istocie zaś planety w okresie sfego ruchu wstecznego świecą jaśniej, a więc wydaje się, że powinny wówczas znajdować się bliżej Ziemi. System sfer współśrodkowych krytykowano w starożytności właśnie za to, że nie potrafił on wyjaśnić zmiennej jasności planet, i większość astronomów porzuciła go, skoro tylko podano bardziej dokładne wyjaśnienie obserwowanych zjawisk" (81-82).

"Nawet dzieła Kopernika obarczone są w poważnym stopniu reliktami tej koncepcji. W tytule więlkiego dzieła Kopernika [...] słowo 'orbes' nie oznacza samych planet , lecz raczej współśrodkowe kuliste powłoki, w któych miały być osadzone planety i gwiazdy" (82).

"Planety i sfery, w których miały być one osadzone, zbudowane być miały z doskonałej substancji niebieskiej, do natury której należał wieczny ruch obrotowy wokół centrum wszechświata" (277).

Arystoteles.
"Zdaniem Arystotelesa cały wszechświat zawarty jest wewnątrz sfery gwiezdnej albo ściślej: ograniczony jest zewnętrzną warstwą tej sfery. W każdym punkcie wewnątrz niej istnieje jakiś rodzaj materii - wszechświat Arystotelesowy nie zna próżni. Na zewnątrz sfery gwiezdnej nie istnieje w ogóle nic - ani materia, ani przestrzeń. Wedle teorii Arystotelesa materia i przestrzeń są nierozłączne, są dwoma aspektami tego samego zjawiska. Pojęcie próżni jest już samo przez się absurdalne. W ten właśnie sposób Arystoteles dowodził skończoności i jedyności wszechświata" Dalej cytaty z Arystotelesa (103).

"Arystoteles nie tylko twierdził, że w świecie ziemskim rzeczywiście istnieje próżnia, lecz że próżnia w ogóle nie może istnieć nigdzie we wszechświecie. Samo istnienie próżni było dla niego czymś logicznie sprzecznym. [...] Przestrzeń nie może istnieć bez materii" (113).

"Niemożliwość istnienia próżni stanowi uzasadnienie skończoności wszechświata. Poza sferą gwiezdną nie istnieje ani materia, ani przestrzeń - nic w ogóle. Bez koncepcji nierozerwalnego związku materii i przestrzeni zwolennicy arystotelizmu uznać by musieli nieskończoność świta. [...] Świat nieskończony nie mógłby być światem Arystotelesowym z dówch chociażby względów. Nieskończona przestrzeń nie ma środka: każdy punkt jest równie odległy od punktów peryferyjnych. Jeśli zaś nie ma środka, to nie istnieje wyróżniony punkt, w którym skupiałby się ważki pierwiastek Ziemi, nie istnieje też kierunek 'ku górze' i 'w dół', który określałby naturalny tuch pierwiastka powracającego do swego miejsca naturalnego. [...] Jeśli przestrzeń jest nieskończona i nie istnieje punkt centralny , to nie widać uzasadnienia, dlaczego cała Ziemia, woda, ogień i powietrze we wszechświecie miałyby skupiać się w jednym i tylko jednym punkcie. [...] Zarówno w starożytności, jak i w średniowieczu większość filozofów uznających - jak atomiści - nieskończoność wszechświata czuła się zmuszona uznać istnienie próżni, a także istnienie wielu światów. Jednakże aż do XVI stulecia nikomu, kto uznawał takie koncepcje, nie udało się stworzyć teorii kosmologicznej, która mogłaby w wyjaśnianiu codziennych zjawisk ziemskich i niebieskich konkurować z konmologią Arystotelesową. Nieskończoność wszechświata może być dzisiaj koncepcją potocznego rozsądku, po to jednak, by tak się stało, zdrowy rozsądek musiał ulec reedukacji. [...] Ruch Zemi [...] nie wymaga ani istnienia próżni, ani nieskończonego wszechświata. Nie jest jednak przypadkiem, że obydwa te poglądy zdobyły uznanie wkrótce po zwycięstwie teorii kopernikańskiej" (114-115).

"Wznajemne oddziaływanie między materią a przestrzenią wyznacza ruch i spoczynek ciał. [...] Zapewne tylko w drodze koincydencji pojęcie przestrzeni występujące w ogólnej teorii względności Einsteina jest, pod wieloma względami, bliższe Arystotelesowemu niż Newtonowskiemu. Wszechświat Einsteina zaś, podobnie zaś do Arystotelesowego, a w odróżnieniu od wszechświata Newtona, może być skończony" (124).

"WIerzył on, że istnieje dokładnie pięćdziesiąt pięć rzeczywistych powłok krystalicznych i że te eteryczne powłoki tworzą mechanizm fizyczny zgodny z matematyczym systemem sfer współśrodkowych, stworzonych przez Eudoksowa i jego następcę Kallipposa. [...] w czasach od Ptolemeusza do Kopernika większość ludzi wykształconych, nie wyłączając astronomów, uznawała, jak sie wydaje, przynajmniej jakąś zwulgaryzowaną wersję sfer Arystotelesowych" (104).

"Arystotelesowy wszechświat zbudowany być może z trzech czy pięciu pierwiastków ziemskich równie dobrze, jak z czterech; może opierać się na koncepcji epicykli lub koncepcji sfer współśrodkowych; nie da się jednak włączyć do niego poglądu, że Ziemia jest planetą. [...] Koncepcja nieruchomej i centralnie położonej Ziemi była jednym z tych niewielu pojęć, które składają się na zwarty i spójny obraz świata" (108).

"Autorytet pism Stagiryty wyrasta częściowo z genialności jego własnych oryginalnych pomysłów, częściowo zaś z ich wielkiego porządku i logicznej koherencji, które dziś wywołują nie mniejsze wrażenie niż ongiś" (121).

Apolloniusz i Hipparch.
"W ciągu siedemnastu stuleci dzielących Hipparcha od Kopernika najbardziej twórczy astronomowie zajmujący się problemami technicznymi usiłowali wymyślać kolejne drone modyfikacje geometryczne, które sprawiłyby, że metoda jednego epicyklu i jednego deferentu zdawać będzie dokładnie sprawę z obserwowanego ruchu planet" (89).

"[...] pozorny konflikt między sferami kosmologii Arystotelesowej a epicyklami i deferentami astronomi Ptolemeusza. Chociaż poprzednio nie zwróciliśmy na to uwagi, teorie te były charakterystycznym wytworem różnych starożytnych cywilizacji, helleńskiej i hellenistycznej. [...] Kosmologiczne ramy starożytnej astronomii są przede wszystkim wytworem tradycji helleńskiej, która znalazła ukoronowanie w twórczości Arystotelesa. Astronomia matematycza Hipparcha i Ptolemeusza należy do tradycji hellenistycznej, która rozkwitła dopiero w dwa wieku po śmierci Stagiryty, lub nawet jeszcze później. [...] Zajmując się [...] matematycznym przewidywanie ruchu planet astronomowie hellenistyczni nie troszczyli się zbytnio o możliwość zbudowania mechanistycznego odpowiednika ich geometrycznych konstrukcji. Fizyczna realność sfer niebieskich i mechanizm wprawiający w ruch utrzymujące się na niebie planety były dla nich zagadnieniami raczej drugorzędnymi. Krótko mówiąc, hellenistyczni uczeni milcząco godzili się na częściowe oddzielenie astronomi od kosmologi; zadowalającą metodę przewidywania ruchu planet stawiali zazwyczaj wyżej niż wymóg kosmologicznej spójności. [...] dotychczasowa niespójność teorii astronomicznej z fizyczną koncepcją poruszających się epicykli i sfer niebieskich [...] traktowali Arystotelesa i Ptolemeusza tak, jakby obaj Ci ludzie żyli w różnej epoce [...] a różnice między ich systemami traktowali niemal jako niespójności tej samej doktryny" (129-130).

Ptolemeusz.
"Sam Ptolemeusz nigdy nie twierdził, że wszystkie okręgi, z których koszysta w Almageście do obliczania położeń planet, są realne fizycznie; były to dogodne narzędzia matematyczne i nie miały być niczym więcej" (218).

Brak teorii impetusu.
"Do czasu reedukacji zdrowy rozsądek mówi nam, że gdyby Ziemia była w ruchu, to powietrze, chmury, ptaki oraz inne obiekty niezwiązane sztywno z Ziemią musiałyby przesuwać się do tyłu" (66).

"Jeśli Ziemia porusza się w trakcie ruchu kamienia lub strzały, to ten czy ta nie mogą dokonyuwać tego ruchu wraz z nią i wobec tego nie mogą spaść w tym punkcie, z którego zostały wyrzucone. [...] impetus [...] kamień będzie podążał za ruchem Ziemi nawet po utracie kontakcu z wyrzutnią. Teoria impetusu pozwala na to, by ruchoma Ziemia nadawała ciałom ziemskim pewną wewnętrzną siłę napędową, która umożliwia im podążanie w ślad za ruchem Ziemi. [...] Teoria impetusu leży u podstaw większości argumentów [...] na rzecz pododzenia ruchu Ziemi z faktem, że rzucony kamień spada w to samo miejsce, z którego został wyrzucony" (147).

Paralaksa.
"Wobec tego, że linie łączące gwiazdę z dwoma przeciwstawnymi punktami orbity ziemskiej nie są do siebie zupełnie równoległe, pozorne położenie kątowe gwiazdy obserwowanej z Ziemi w dwóch różnych porach roku nie jest takie samo" (193).

Planety.
Pierwszy, który wysunął problem planet był Platon (78).
"Planety przesuwają się zazwyczaj poprzez konstelacje w kierunku wschodnim; jest to tak zwany 'ruch normalny'. Średnio czas obiegu zodiaku przez Merkurego i Wenus wynosi rok; cykl Marsa trwa przeciętnie 687 dni, Jowisza - 12 lat, a Saturna - 29 lat. Jednak we wszystkich tych przypadkach czas poszczególnego obiegu różnić się może znacznie od wartości średniej. Nawet wówczas, gdy planety przesuwają się względem gwiazd w kierunku wschodnim, prędność ich ruchu nie jest jednostajna. [...] Normalny ruch [...] w kierunku wschodnim, z wyjątkiem księżyca i Słońca, bywa od czasu do czasu przerywany przez krótkie okresy ruchu w kierunku zachodnim, czyli 'ruchu wstecznego'. [...] Merkury zwraca swój bieg względem gwiazd w kierunku zachodnim raz na 116 dni, a wenus raz na 584 dni. Dla Marsa, Jowisza i Saturna okresy te wynoszą odpowiednio 780, 399, 378 dni" (69-70).

Kepler.
"Kierując się stale swą neoplatońską postawą wobec Słońca, Kepler wprowadził siły emanujące ze Słońca i planet. W ten sposób chciał on uzyskać przyczynowe wyjaśnienie ruchu planet. W jego pracach wszechświat po raz pierwszy przedstawiony został jako ziemski układ mechaniczny" (279).

Faktyczna nicość rewolucji jako takiej.
"Wszechświat kopernikański sam jest produktem szeregu badań, które umożliwiły powstanie koncepcji świata dwusferycznego; koncepcja Ziemi jako ruchomej planety jest najbardziej skrajnym przykładem skuteczności wskazuwek, jakch dostarczała nauce - nie dająca się z tamtą pogodzić - teoria przedstawiająca Ziemię jako nieruchomą i centralnie położoną. [...] Wszechświat dwusferyczny jest ojcem wszechświata kopernikańskiego, żaden bowiem schemat teoretyczny nie rodzi się bowiem z niczego" (63).

"[...] astronom, uznający [...] dwusferyczny model wszechświata, będzie starał się wykryć w przyrodzie zjawiska czy własności dotąd jeszcze niezaobserwowane, lecz przewidziane na podstawie schematu pojęciowego. Dla niego teoria wykraczać będzie poza granice tego, co znane, stając się przede wszystkim potężnym środkiem przewidywania i badania tego, co jeszcze nieznane. Wpłynie ona zarówno na przyszłość nauki, jak i na jej przeszłość" (62).

"Astronomowie europejscy, jak Brahe, czy Kepler, którzy w okresie późnego Odrodzenia nadali systemowi kopernikańskiemu kształt niewiele już różniący się od współczesnego, korzystali z finansowania i intelektualnego poparcia dlatego, że sądzono, iż potrafią stawiać najlepsze horoskopy. [...] Znamienne jest także, iż Kopernik, twórca teorii pozbawiającej ostatecznie niebiosa ich szczególnej mocy, należał do tych nielicznych astronomów Odrodzenia, którzy nie stawiali horoskopów" (118-119).

"Znaczenie De Revolutionibus polega zatem w mniejszym stopniu na tym, co dzieło samo mówi, niż na tym, co dzięki niemu powiedzieli inni. Jest to tekst raczej rowoluzjonizujący niż rewolucyjny. [...] Tekst rewolucjonizujący stanowi zarówno kulminacyjny punkt rozwoju starej tradycji, jak i źródło przyszłej nowej. [...] Jest to dzieło zarazem starożytne i nowożytne, zarazem konserwatywne i radykalne" (162-163).

"[...] ciągła zależność od Arystotelesowych i scholastycznych koncepcji i praw wskazuje, w jak niewielkim stopniu we wszystkich innych dziedzinach poza swą specjalnością zdolny był Kopernik - nawet on - wyjść poza ramy swego wykształcenia i swoich czasów" (172).

"Pod pewnymi względami jest on nawet bardziej arystotelesowski niż wszechświat przedstawiany przez wielu jego poprzedników i współczesnych. Kopernik nie chciał np. zgodzić się na odstąpienie od koncepcji jednostajnego i symetrycznego ruchu sfer, związanej implicite z pojęciem ekwantów" (176).

"Wobec tego, że Kopernik zbudował pierwszy kompletny system astronomiczny oparty na koncepcji ruchomej Ziemi, nazywa się go często pierwszym nowożytnym astronomem. Jak wskazuje jednak tekst ' De Revolutionibus', z równym powodzeniem nazywać go jednak można ostatnim wielkim astronomem ptolemeuszowym. Astronomi Ptolemeusza to coś o wiele więcej niż system oparty na założeniu nieruchomości Ziemi, a Kopernik zerwał z tradycją ptolemeuszową tylko pod tym jednym względem" (212-213).

"Należał on do odrodzonej tradycji hellenistycznej astronomii matematycznej, która kosztem problemów kosmologicznych kładła nacisk na matematyczne zagadnienie ruchu planet. Dla jego hellenistycznych poprzedników fizyczna paradoksalność epicykli nie stanowiła zasadniczego mankamentu systemu Ptolemeusza i Kopernik okazywał podobną obojętność wobec szczegółów kosmologicznych, kiedy nie udawało mu się wspólnie powiązać koncepcji ruchomej Ziemi z tradycyjnym schematem wszechświata" (214-215).

"W systemie Kopernika główne nieregularności ruchu planet mają charakter tylko pozorny. Regularny ruch planet obserwowany z ruchomej Ziemi [tylko] wydaje się nieregularny. Z tego względu, sądził Kopernik, powinniśmy uznać orbitalny ruch Ziemi" (178).

"Jest to schemat pojęciowy, który pozwalał na przejście od geocentryzmu do heliocentryzmu, nie zrywając przy tym z Arystotelesowską koncepcją wszechświata. [...] Kopernikowi nie udało się przedstawić odpowiedniej fizycznej teorii ruchu. [...] konsekwencje jego reformy astronomicznej wykraczają poza problematykę z której się ona zrodziła [...] autor reformy [w niewielkim stopniu] zdolny był pojąć przewrót, któremu dało początek jego własne dzieło. Wszechświat Kopernikański jest jeszcze skończony, a koncentryczne sfery nadal porusząją planety, choć samym tym sferom nie nadaje ruchu sfera zewnętrzna, która znajduje się w spoczynku" (184).

"Kopernik przypisał Ziemi trzy jednoczesne ruchy kołowe: dzienny obrót wokół własnej osi, roczny obrót po orbicie okołosłonecznej i roczny ruch precesyjny osi ziemskiej" (185).

"W istocie jego zdaniem znajdować się ona [Ziemia] musi względnie blisko środka, i tak długo, jak znajduje się blisko niego, może się wokół niego poruszać, nie naruszając zarazem pozornego ruchu gwiazd. [...] Kopernik był zmuszony znacznie powiększyć wymiary sfery gwiezdnej i tym samym uczynić pierwszy krok ku koncepcji wszechświata nieskończonego opracowanej później przez jego następców" (187).

"Jego zdaniem Ziemia jest planetą, którą wokół Słońca unosi taka sama sfera, jaka poprzednio unosić miała Słońce wokół centralnie położonej Ziemi" (195).

"Tak np. system Kopernika nie był w gruncie rzeczy systemem ściśle heliocentrycznym" (200).

"Przedmowa do 'De revolutionibus' zaczyna się od oskarżenia atronomii Prolemeusza o brak precyzji, skomplikowany charakter i niespójność; nim jednak Kopernik zdołał dokończyć swoje dzieło, obarczył je tymi samymi wadami. System kopernika nie jest ani prostszy, ani bardziej dokładny od Prolemeuszowego. [...] Te cechy starożytnej tradycj, które doprowadziły Kopernika do próby radykalnej reformy, nie zostały przez tę reformę wyeliminowane. [...] Jakiś nowy Kopernik mógłby skierować te same argumenty przeciwko niemu" (202).

"System ten tłumaczy zasadnicze jakościowe cechy ruchu olanet nie odwołując się do epicykli. [...] Jednakże tylko atronom, który ceni wyżej jakościowy ład od ilościowej dokładności [...] uznać to może za przekonywający argument w zestawieniu ze skomplikowanym systemem epicykli i ekscentryków przedstawionym w 'De revolutionibus'" (203).

"Sam Kopernik korzystał przecież ze sfer dla wytłumaczenia ruchu planet" (239).

Filozoficzne skutki rewolucji.
"Ludzie przekonani, że Ziemia, na kórej żyją, jest tylko jedną z planet ślepo obracających sie wokół jednej z nieskończonej ilości gwiazd, oceniać będą swe miejsce we wszechświecie zgoła odmiennie niż ich przodkowie, którzy mniemli, że Ziemia jest wyróżnionym i centralnym obiektem boskiego stworzenia. Dlatego też przewrót kopernikański oznaczał zarazem zmianę systemu wartości uznawanych przez człowieka" (20).

"Jeśli pominąć ewentualnie Arystarcha, Kopernik był pierwszym, który zdał sobie sprawę, że ruch Ziemi rozwiązać może istniejący problem astronomiczny, a w gruncie rzeczy wszelki problem naukowy. Nawet jeśli uwzględnimy Arystarcha, to Kopernik był pierwszym, który przedstawił szczegółowy opis konsekwencji ruchu Ziemi" (171-172).

Koniec miejsca.

[zakariah · Rating 2 out of 5]

“development of western thought” ok but homie u didn’t have to be THAT racist ???

[Ari · Rating 4 out of 5]

This book is one of the most inspiring -- and most humbling -- books that I've read in quite some time.

I've been interested in astronomy since I was a kid, so the story of Copernicus and Kepler is one I thought I knew. But Kuhn brings out several aspects I hadn't understood before. Kuhn draws attention to something that's often overlooked: Ptolemaic astronomy isn't actually quite compatible with Aristotelian cosmology. The inconsistency wasn't noticed because mathematical astronomy at the time was a very narrow technical field, whose practitioners weren't interested in pushing on physics and who in turn escaped notice from the mainstream of natural philosophy.

Kuhn also points out something else that should be better known: the Church condemned heliocentrism very late. Copernicus's book is published in 1546. By the time it was condemned in the 1620s, a huge pile of evidence had been discovered in favor of it, and professional opinion was swinging decisively behind it.

[Elizabeth · Rating 4 out of 5]

I'm not sure I understood any of the science and math but this book was fabulous in laying out the intellectual history of the time. I really loved reading those sections.

[reoccurrence]

Putting this down after reaching page 133. I wanted a book that featured a short but detailed history of astronomy up to Ptolemy and this book is exactly that. I will be picking this back up when it’s time for me to visit Copernicus and his influence on Astronomy.

[Laura L. Van Dam · Rating 3 out of 5]

Que me perdone Kuhn pero es muy repetitivo el libro. Y repite casi párrafos enteros de otros libros que he leído, me interesa el tema pero la verdad se me dificultó terminarlo. No sé si aporta mucho pero tiene algunas secciones interesantes sobre como pasa de Ptolomeo al heliocentrismo ( no es tan lineal como parece)

[Matthias · Rating 5 out of 5]

The most riveting intellectual history I have read since Lovejoy's "Great Chain of Being," this is a book replete with historical empathy, copious, starkly beautiful diagrams, and a keen sense of the ironies of history.

[Ivana Olson · Rating 1 out of 5]

So ridiculously boring. Out of date and hard to follow.

[Catherine · Rating 5 out of 5]

I was not expecting to like this, because science. I loved it, because SCIENCE!

[A YOGAM · Rating 4 out of 5]

Die kopernikanische Revolution: Eine wissenschaftstheoretische Fundamentalanalyse
Thomas S. Kuhns Werk „Die kopernikanische Revolution“ (1957) besitzt herausragende wissenschaftstheoretische Bedeutung, da es die historische Fallstudie darstellt, auf deren Grundlage er wenige Jahre später die zentralen Konzepte seines epochalen Hauptwerks „Die Struktur wissenschaftlicher Revolutionen“ (1962) entwickelte. Das Buch ist daher weit mehr als Wissenschaftsgeschichte: Es ist Wissenschaftstheorie in historischer Anwendung.
Das Paradigma der Normalwissenschaft
Kuhn präsentiert das ptolemäische System, das die Erde ins Zentrum des Universums stellte, als exemplarisches wissenschaftliches Paradigma.
Fundamentale Einheit: Das geozentrische Weltbild verband Himmelsmechanik, aristotelische Physik und christliche Theologie zu einer geschlossenen, in sich stimmigen Kosmologie.
Rätsellösung (Puzzle-Solving): Die Astronomen der Normalwissenschaft beschäftigten sich nicht mit der Falsifikation des Paradigmas, sondern mit der Bewältigung von Anomalien. Sie suchten durch die Anhäufung geometrischer Zusatzstrukturen – Epizykel, Exzentriker, Äquanten – die wachsenden Beobachtungsprobleme zu lösen. Für Kuhn ist diese zunehmende Komplexität ein Zeichen dogmatischer Erstarrung, nicht echten Fortschritts.
Akkumulation von Anomalien und Krise
Kuhn zeigt, dass die kopernikanische Wende nicht durch eine einzelne zwingende Beobachtung ausgelöst wurde (im Gegensatz zu Poppers Ideal der Falsifikation), sondern durch eine Krise, die aus der ästhetischen, mathematischen und konzeptuellen Überfrachtung des geozentrischen Modells entstand.
Das ptolemäische System war so mit Ad-hoc-Hilfskonstruktionen gesättigt, dass es unhandlich, unübersichtlich und zunehmend inkonsistent wurde. Dieser strukturelle Verschleiß unterminierte das Vertrauen in das Paradigma selbst – die Voraussetzung jeder wissenschaftlichen Revolution.
Revolution und Inkommensurabilität
Der Übergang zum heliozentrischen System illustriert Kuhns Grundthese exemplarisch:
Nicht-kumulativer Bruch: Kopernikus’ Modell war bei seiner Veröffentlichung dem ptolemäischen nicht sofort empirisch überlegen. Seine Attraktivität lag in der konzeptuellen Einfachheit und der harmonischen Erklärung zentraler Phänomene (etwa der retrograden Planetenbewegung). Der Paradigmenwechsel vollzog sich als Gestaltwandel im Weltbild, nicht als schlichte Verbesserung innerhalb desselben Rahmens.
Inkommensurabilität in Aktion: Die anfänglichen Akzeptanzprobleme – insbesondere die Frage nach der Erdbewegung, die der damaligen Physik widersprach – illustrieren die Inkommensurabilität alter und neuer Paradigmen. Erst die neuen theoretischen Grundlagen bei Kepler, Galilei und Newton machten das heliozentrische Weltbild rational verbindlich.
Wissenschaftstheoretisches Fazit
„Die kopernikanische Revolution“ ist die historische Blaupause für Kuhns Theorie: Wissenschaftlicher Fortschritt verläuft nicht linear und kumulativ, sondern episodisch und revolutionär. Normalwissenschaft ist eine Phase des stabilen Dogmas; wissenschaftliche Revolutionen entstehen, wenn ein Paradigma aufgrund wachsender Anomalien zerbricht und durch ein inkommensurables ersetzt wird – oft aus Gründen, die ästhetische Eleganz ebenso einschließen wie empirische Bewährung.
Das Werk bleibt eine unverzichtbare Lektüre für alle, die die Entstehung der historischen Schule der Wissenschaftstheorie in ihrem methodischen Kern verstehen wollen.

[Crito · Rating 5 out of 5]

It would be wrong to approach this as a case study for The Structure of Scientific Revolutions, or at least prove a dull exercise in it. Instead this book should be understood foremost as a fantastic work of scholarship, which manages to be accessible without sacrificing rigor of technical exposition, and which has a wide breadth while remaining economical and focused. While Kuhn doesn't refrain from commentary, what he succeeds in doing is to underline the implications and importance of the key question of the Copernican Revolution given the facts: what reason would a scientist (or philosopher) have for preferring the Copernican model over the Ptolemaic? With access to the same dataset Copernicus offered a rough geometric equivalent of the Ptolemaic system which, despite dispatching aspects of Ptolemaic astronomy which Copernicus thought superfluous and ugly, was ultimately not more simple or accurate in respect to the data. Why prefer one and dispatch the other? Often we arrive at better models by simply pushing the rigor of our current ones. As Chomsky put it in Syntactic Structures, "By pushing a precise but inadequate formulation to an unacceptable conclusion, we can often expose the exact source of this inadequacy and, consequently, gain a deeper understanding of the ... data." In contrast, Copernicus's innovation was not so directly iterative, and as Kuhn points out, was as much flavored by ideological (Neoplatonic) underpinnings as the scholastic understanding of the Ptolemaic model (Aristotelian). It then becomes the legwork of scientists and philosophers to make sense of this, and while you can see how this prefigures Kuhn's SSR, he isn't pushing that angle as much as you would expect if you took this as a case study for that book. Instead it outlines the history (scientific, philosophical, and sociological) which is relevant to the question. And in the meantime you learn a lot about astronomy and the development of science in the process. Strong Recommendation.

[Juanjo Galvez · Rating 5 out of 5]

📖 La revolución copernicana - Thomas S. Kuhn

🌟🌟🌟🌟🌟

El famoso "La revolución copernicana" de Thomas S. Kuhn se sumerge en el profundo cambio paradigmático que introdujo Copérnico en nuestra comprensión del cosmos. Kuhn, conocido por sus teorías sobre los cambios científicos y las estructuras de las revoluciones científicas, presenta aquí una obra maestra que ilumina cómo se llevó a cabo este cambio monumental y qué significó para el progreso científico.

🔭 Resumen:
En este libro, Kuhn traza el desarrollo del modelo heliocéntrico de Copérnico y cómo desafió el modelo geocéntrico previamente aceptado. Más allá del mero hecho histórico, Kuhn examina las resistencias, implicaciones y las profundas transformaciones que este cambio trajo para la ciencia y la sociedad.

📚 Pros:

✅ Kuhn proporciona un análisis profundo, no solo del cambio científico, sino también de la resistencia cultural y las implicaciones filosóficas de la revolución copernicana.
✅ La prosa es clara y articulada, haciendo que un tema complejo sea accesible para una amplia audiencia.
✅ Ofrece perspectivas sobre la naturaleza de la ciencia y cómo las ideas revolucionarias pueden alterar radicalmente las creencias establecidas.
🚫 Contras:

❌ Aunque el libro es detallado, su nivel de profundidad podría ser un desafío para aquellos no familiarizados con la historia de la ciencia o la filosofía de la ciencia.
❌ Algunos podrían encontrar la discusión sobre paradigmas y resistencias a nuevas ideas un poco repetitiva.
📌 Conclusión:
"La revolución copernicana" es una lectura esencial para cualquiera interesado en la historia de la ciencia, la filosofía de la ciencia, o simplemente en cómo las ideas revolucionarias pueden transformar la comprensión del mundo. Kuhn, con su meticuloso análisis, brinda valiosas lecciones no solo sobre el pasado, sino también sobre cómo las revoluciones científicas pueden formarse y ser aceptadas en el futuro. Una obra profundamente enriquecedora que se merece su estatus icónico.

[Justine Cheng · Rating 5 out of 5]

Really great book. I skipped a lot of the technical explanations due to time constraints, but he really does an incredible job of contextualizing Copernicus within ancient and medieval astronomy while also showing how Copernicus' developments internal to astronomy reached beyond the field. Telling the story of how the heavens became subject to terrestrial physics from Copernicus to Galileo to Descartes to Newton is really effective. Rigorous and thorough as far as I can tell. Extremely useful for contextualizing the stakes of Kant and Freud's invocation of the copernican turn, Lacan's interest in the ellipse of copernican thought and Sylvia Wynter's critique of the Copernican turn. Really really helpful for understanding the discourse that Wynter is speaking into.

Lacan also offers a fundamental critique of Kuhn's orientation of science towards belief in the world/at-homeness. Is it belief or doubt which motivates Copernicus's discovery?

I also recently finished Jameson's Geopolitical aesthetics recently and I can't help but find his argument for the periodization of postmodernity to be pretty thin. I don't really see how material or even epistemic shifts account for the emergence of the narrative forms he describes. They seem to have much more to do with Copernicus' planterization of the earth and Newton's emptying of space. The shift from earth as center to, per Kuhn's etymology, planet meaning 'wanderer' is reflected in the drifting narratives that Jameson exams. The narrative logic of conspiracy is reflected in the corpuscularism of Descartes in which cause is at once plentiful and contingent. The pluralization and relativization of the world seems reflective of how the positing of a planetary earth presented the idea of numerous other life bearing earths. The opening scene of Bela Tarr's Werckmeister harmony makes the connection between the Copernican universe and postmodern narrative pretty explicit. https://www.youtube.com/watch?v=_d5X2...

[Carlos · Rating 2 out of 5]

Having thoroughly enjoyed “The Structure of Scientific Revolutions” by Kuhn, I was excited to read this book. However, while there certainly was an interesting argument in this book but it was a bit overwhelmed by the force with which Kuhn wanted to reader to understand its astronomical foundations. These started out simple enough with discussions about solar dials and basic astronomical observations, however they progressively increased to the point that Kuhn himself decided to make a technical appendix to deal with them. Given that, it surprised me that Kuhn still felt compelled to include ever more complex discussions of Ptolemaic epicycles and the like in the main body of the text instead of relegating them to the appendix where the interested reader might peruse them at length. Similarly, Kuhn drowned his main argument for the development of the Copernican Revolution by trying to link it through succeeding generations of scientist to Newton’s work, increasing yet again the discussions of evolving mathematical techniques. I found all of this distracting because his main argument could be readily understood without such mathematical emphasis. His discussions of the evolving intellectual climate prior to Copernicus’ work, the innovations as well as limitations of Copernicus own work as well as the subsequent work by Tycho Brahe and Johannes Kepler were simply amazing. It is this aspect of the book that kept me reading. Kuhn really fleshes out the intellectual world that permeated Copernicus’ thought and strives to explain why the Copernican revolution happened when it did or happened at all. It honestly felt as if this work needs a good editor to make an abridged edition to make it shine.

[Brook · Rating 4 out of 5]

This book brought the clarity I needed to fully appreciate Kuhn's main thesis he would develop throughout his lifetime in Structure and beyond. What I felt was lacking from Structure was a fully developed, concrete example where I could see his ideas of paradigm shift in progress in an actual historical moment. It's clear from reading this book that this was his original case study, and the transformation he generalized to speak about other scientific revolutions.

For anyone interested in Kuhn's ideas, I would definitely recommend reading this _before_ reading Structure. Structure is basically just an abstraction of what is studied in this text.

I also think this book does a great job and complicating the simple narrative that opposition to Copernican science was simply conservative Church dogma. Aristotelianism, the main scientific influence on Church thought, was a totalizing system explaining everything from the motion of rocks to the germinating of seeds and ever star in the heavens. Each piece of the system depended on all the others, and one could not take down one without destabilizing the others. It also becomes clear as you read that in different epochs, different flavors of explanations are permitted or not permitted. The best example being that Newton believed he had failed to explain gravity, for just positing that particles attracted each other as a matter of their nature was considered "Aristotelian" but was clearly afterward accepted as a valid scientific explanation.

[Justin · Rating 5 out of 5]

Among the infinite conceptions of the universe, science favors those that are most unified with experience and with each other. In its drive towards oneness, science is a sort of mysticism. New conceptions are often originally conceived by those seeking order despite the lack of experience that shows that it’s actually there. It’s a guess, or a hope, or an ideal that derives coherence in the world and makes sense to the thinker. This was the case for Copernicus, and Aristotle before him. In the early days of modern western thought, it was also the case for those who made progress that revealed Copernicanism to be a better fit with experience than previous conceptions. Of course, anyone doing work towards what has not yet been demonstrated appears a fool to all of whom are not on board with the starry-eyed new view. And dogma will perpetuate potentially false views, whether they have any sort of demonstration or not. Kuhn makes the example of the Copernican Revolution particularly accessible by his thorough description of astronomical observations with which thinkers grappled. The interplay of observation, philosophy, religion, and science across history is fascinating. It’s an illumination of how ideas work. Technology played an important role in the Copernican Revolution, particularly as a catalyst, but was not required. The story that Kuhn presents is one of the clearest cases of thought revolution, and perhaps it is a macrocosm of the churn of ideas in society, or in oneself.

[Ethan Hammons · Rating 5 out of 5]

I decided to read this after hearing about Kuhn's magnum opus, The Structure of Scientific Revolutions. Since middle school I had gotten very small tidbits about the Copernican Revolution, usually condensed into half a single lecture at the beginning of the year. But in light of Kuhn's analysis of how thought systems evolve, I was curious how significant this point in history was. Kuhn does a great job of showing it.

The book has a very thoughtful structure consisting of the technical breakdown of the old astronomical system, the cultural atmosphere that system was embedded in, the weaknesses in it that Copernicus sparked the future solutions for, the resistance to his ideas, and their ultimate assimilation. The book is filled with beautiful diagrams that make understanding the concepts much easier. I was blown away by the beauty of the old astronomical model, which though false were quite good at making predictions.

I think someone who is more familiar with Platonic or Neoplatonic philosophy will get more out of this book than most. Much of the frameworks that informed the Copernican Revolution (and the Renaissance) came from the reintroduction of these Neoplatonic texts that has been lost since the early Middle Ages. A lot of this is explored in the book, and while I don't think it's required to know it beforehand to enjoy it, you will definitely get more out of it. Check out Proclus!

Overall, I thoroughly enjoyed it. I don't enjoy history books much but this was right up my alley. I look forward to finally reading his masterwork.

[Farid Medleg · Rating 3 out of 5]

3.5/5

A thoughtful review of the evolution of scientific thought, particularly in Europe, in the 16th and 17th centuries.

Kuhn does an admirable job of infusing his historical review with technical analysis.

Somewhat expected, though nevertheless disappointing, was his hand-waving of how much Western thought was dependent upon Eastern and Islamic progress. At times, the inception of critical ideas by primarily Islamic scientists is given only a cursory mention before heaping all praise on "Renaissance" scientists. In other instances, discoveries and scientific achievement are incorrectly attributed to Western scientists when they were actually due to Islamic/Eastern scientists centuries earlier.

While this phenomenon is in part due to discoveries made after the publication of this book, a bias towards "Western" thought still permeates this work.

More recent publications present a far more balanced picture:
-George Saliba — Islamic Science and the Making of the European Renaissance (2007)
-A. I. Sabra — The Optics of Ibn al-Haytham
-David A. King — In Synchrony with the Heavens (2004)
-F. Jamil Ragep — Nasir al-Din al-Tusi’s Memoir on Astronomy
-George Saliba — A History of Arabic Astronomy (1994)
-Nilüfer Akçay & Robert Morrison — works on Ottoman astronomy
-Toby Huff — The Rise of Early Modern Science
-The Cambridge History of Science, Volume 2

[Dan · Rating 5 out of 5]

A solid addition to the literature of science history and intellectual history. Kuhn sets out the interesting ways by which the astronomical system of Copurnicus generated the revolution named for him.

The book is interesting in detail and breadth and is fairly easily reading not compromised by philosophical obfuscation. I do not sense that Kuhn is out of his depth at any point. He exaggerates his viewpoint only somewhat. I believe it will interest any non-scientist as well as any scientist not already familiar both with the historical details presented and with their significance in a historical view reaching back to Aristotle and forward to Newton. There are some simple diagrams which require attention, but few of them need to be studied so long as the reader understands from the text their meaning. Similarly, no math is needed. Any layman who believes science is mostly a collection of facts must read this in order to have a sense of a type of process that science is truly about.

Importantly, the Copernican (sun-centered) astronomy, says Kuhn, resulted in no obvious overall simplification over the Ptolemaic system (with epicycles, which are moving circles within orbits and had been adopted along with other unrealities in order to describe the apparent motions of the heavens around the earth). Copernicus did not, for example, eliminate most of the epicycles. While he did simplify some matters, he rendered others more complicated. For example, in order to make his system correspond to observation, he had to add some (unreal) motion not present in Ptolemy. The primary task for Copernicus was to prove mathematically that his system was observationally consistent with Ptolemy, since the received Ptolemaic system was as accurate as current observations allowed and was, as shown by Kuhn, accurate generally to a degree which the Copernican description did not exceed. The superiority his new system was not at all clear.

(It was a problem with the calendar that likely motivated Copernicus to look for a better system. Ironically, It was a church authority who asked him whether he could resolve the problem. Furthermore, his formulation did not finally result in a solution to it.)

Why and how then did the Copernican revolution result? While its influence tends to be considered in terms of its theological and philosophical implications, the answer to the question lies elsewhere, since this was fundamentally a scientific revolution.

This question presents to the historian a challenge which Kuhn masters in this book. He shows that some of the answer lies in the historical significance of modest ad hoc evolutionary accretions made to Ptolemaic astronomy before Copernicus. (More, below.)

Much else lies in the incremental recognition by post-Copernican astronomers of various advantages of this system, quite small advantages early on. These advantages could not be seen until later (initially in large part because of improvements made in the accuracy of astronomical observations after he died). They accumulated and supported one another, along with successive theoretical modifications over time, to the extent that his system largely has been replaced. Today it can as easily be seen as more nearly Ptolemaic than as Newtonian or Einsteinian.

But similar as the views of Ptolemy and Copernicus were, the revolution would not have arisen from a Ptolemaic view, because the evolution of that view would have continued the same way it always had since the time of Ptolemy, by adding additional epicycles and other unrealities whenever necessary in order to fit new data, as indeed Ptolemy had done to the Aristotelian cosmology in order to arrive at his own. Copernicus proved that an abrupt disruption in this kind of evolutionary procession, by moving the center of the universe from earth to sun rather than adding more epicycles, could result in an equally acceptable astronomy. The change in the process itself, this fundamental difference in procedure only, became a leap more important than any immedate astronomical consequences of the new theory.

But this change could not be appreciated at first. In the larger scientific community of the decades after his death, even the sun-centered nature of the theory was largely ignored, as it contradicted the senses, tradition and religious authority. It became preferentially taught because it clearly set out in one elegant treatise the means of making mathematical calculations describing celestial observations. (The Ptolemaic formulation had passed through the centuries in often second-hand accounts and varying translations and re-translations, additions and other editing.) Only as increasingly accurate astronomical data more strongly matched the Copernican universe did the teaching of his system to other scientists become securely established.

Only later as the remaining Ptolemaic elements fell away due to more sophisticated data collection and more ingenious mathematical treatment did the best mathematicians begin to appreciate more fully the scientific value of the new and evolving system. Since the Copernican leap in process had already been proved by him to lead to a defensible scientific result, and the conception was proving even more useful over time, mathematicians were now at liberty to attempt further procedural leaps of imagination in search of better answers. Importantly, they could find increasingly general formulations (like universal gravity) in order to explain and simplify elegantly a greater number of observations, rather than further complicate matters as would result by piling on more epicycles. The revolution is named for Copernicus because he afforded this new liberty of scientific imagination which eventually proved so fruitful.

Only after the newer formulations proved their power could the wider scientific community and then the educated public begin fully to accept the revolution and attempt reasonably to assess what broader implications might be implied by this revolutionary theory.

[David · Rating 5 out of 5]

A very, very good book for science and history buffs. I read Kuhn's classic book: The Structure of Scientific Revolutions, some years ago but found it too philosophical or esoteric for my tastes. The Copernican Revolution offers a much more accessible account of a scientific revolution unfolding through the centuries.

The common-sense, earth-centered Ptolemaic universe inherited by Copernicus was more than just a mental model of how the world was structured in a physical sense. It was a worldview steeped with religious overtones about Man's place on Earth in relation to the perfect heavens above. Beyond the outermost sphere of the stars was God in Heaven who had set that sphere in motion. In turn, that motion set the other planetary spheres in motion above the solid, immobile Earth.

But those perfect circular orbits were not what Ptolemy and many other astronomers through the centuries actually observed. There were inconsistencies in the planets' orbits which didn't fit the worldview. Ptolemy and others added circles (epicycles) to circles to try to account for the irregular motions, adding more and more complexity to the music of the spheres.

Copernicus sought to simplify matters by moving the Sun to the center of the universe, and by moving the now-rotating Earth into orbit around the Sun along with the other planets. He still kept some aspects of the Ptolemaic system, such as the crystalline spheres and some epicycles, but the Copernican system was a bit simpler and a lot more "aesthetic". There was a "new neatness and coherence in the sun-centered astronomy of Copernicus." (Page 171.)

It took the work of other astronomers to fully flesh out the Copernican revolution. Tycho Brahe, Kepler and Galileo added further insights and more accurate observations to further explain a world which was becoming much more interesting and surprising than the old world of spheres within spheres.

Before Galileo, Copernicus' theory was simply a mathematical model used only by technically trained astronomers. But things changed when Galileo pointed his telescope to the night sky and observed the new moons of Jupiter, the phases of Venus, and the cratered face of our Moon:

With the advent of the telescope Copernicanism ceased to be esoteric. It was no longer primarily the concern of highly trained mathematical astronomers. Therefore it became more disquieting and, to some, more dangerous....After Galileo had announced his observations in 1610, Copernicanism could not be dismissed as a mere mathematical device, useful but without physical import. Nor could even the most optimistic still regard the concept of the earth's motion as a temporary lunacy likely to vanish naturally if left to itself. The telescopic discoveries therefore provided a natural and appropriate focus for much of the continuing opposition to Copernicus' proposal. They showed the real cosmological issues at stake more quickly and more clearly than pages of mathematics. (Page 226.)

And it was more than learned men who were looking at the new world unfolding above them:

The telescope became a popular toy. Men who had never before shown interest in astronomy or in any science bought or borrowed the new instrument and eagerly scanned the heavens on clear nights. The amateur observer became a well-known figure, a subject for both emulation and parody. With him came a new literature. The beginnings of popular science and science fiction are to be discovered in the seventeenth century, and at the start the telescope and its discoveries were the most prominent subjects. That is the greatest importance of Galileo's astronomical work: it popularized astronomy, and the astronomy that it popularized was Copernican. (Page 225.)

Official opposition to Copernicanism began in earnest after Galilleo's discoveries which offered evidence supporting the Copernican view of the universe. This opposition grew out of a

subconscious reluctance to assent in the destruction of a cosmology that for centuries had been the basis of everyday practical and spiritual life. The conceptual reorientation that, after Kepler and Galileo, meant economy to scientists frequently meant a loss of conceptual coherence to men like Donne and Milton whose primary concerns were in other fields, and some men whose first interests were religious, moral, or aesthetic continued to oppose Copernicanism bitterly for a very long time. (Page 226.)

But denying the true nature of the world and how the universe works can only continue for so long:

old conceptual schemes do fade away...During the century and a half following Galileo's death in 1642, a belief in the earth-centered universe was gradually transformed from an essential sign of sanity to an index, first, of inflexible conservatism, then of excessive parochialism, and finally of complete fanaticism. By the middle of seventeenth century it is difficult to find an important astronomer who is not Copernican; by the end of the century it is impossible. Elementary astronomy responded more slowly, but during the closing decades of the century Copernican, Ptolemaic, and Tychonic astronomy were taught side by side in many prominent Protestant universities, and during the eighteenth century lectures on the last two systems were gradually dropped. Popular cosmology felt the impact of Copernicanism most slowly of all; most of the eighteenth century was required to endow the populace and its teachers with a new common sense and to make the Copernican universe the common property of Western man. The triumph of Copernicanism was a gradual process, and its rate varied greatly with social status, professional affiliation, and religious belief. But for all its difficulties and vagaries it was an inevitable process. (Page 227.)

[Elia Mantovani · Rating 3 out of 5]

"La rivoluzione copernicana" rappresenta uno dei casi-studio le cui tendenze si rtiroveranno poi nella "Struttura". Kuhn esamina la storia della rivoluzione copernicana prendendola molto larga e sottolineando le continuità nella ricerca scientifica dalle cosmologie presocratiche sino al telescopio di Galileo. L'approccio filosofico è puramente kuhniano e cerca infatti di abbraccia un'idea di scienza molto più larga rispetto alle evidenze o alle prove sperimentali. Penso che i passaggi più interessanti possano essere quelli che riguardano la nozione di paradigma (qua ancora "schema concettuale") in quanto già preludenti una prospettiva molto più astratta che troverà concretizzazione nella Struttura. Di fatto la maggior parte del testo è incredibilmente tecnico, a volte addirittura inaccessibile senza nozioni scientifiche radicate.

[El Bibliófilo · Rating 5 out of 5]

My comments in video: https://youtu.be/hsB8HyeAmYE

Mis críticas al gran historiador y filósofo de la ciencia
Luego de mis comentarios sobre la carta a Cristina de Lorena de Galileo Galilei, y sobre las revoluciones de Copérnico, era inevitable y lógico continuar con la lectura de esta obra, del científico, historiador y filósofo de la ciencia norteamericano. Aprovecho los impulsos y la motivación de las lecturas que están tan íntimamente relacionadas para dejarme llevar por el impulso.
Acá les presento los pensamientos y reflexiones de esta maravillosa lectura, y los animo a realizarla, pues complementa las anteriores y abre nuevas perspectivas.
Al final, les comparto un argumento que inicialmente pensé que apoyaba a Irene Vallejo en "el infinito en un junco", pero que me animó a pensar profundamente.
Espero sus comentarios.

[Fernando Pestana da Costa · Rating 5 out of 5]

A wonderful work about the Copernican revolution in which this landmark event in the history of Science (and of Ideas) is put into perspective by a masterful presentation of previous worldviews (the two spheres universe, the Ptolomaic system, the Aristotelian universe and its scholastic critiques) and of the Copernic system, with its immense physical and philosophical consequences. The opposition to Copernicism (at times of a rabid violence) as well as its progressive acceptance and the scientific inquires originated by the attempts to reconcile it with the physics (attained, only much latter, by Newton) is masterfully narrated in this classic of the History of Science that can still be read with much pleasure and profit more than fifty years after its first edition, in English, in 1957.