Hi, first time here and English-Is-Not-My-Native_Language^TM , so please go easy on me...
I found myself on the Wikipedia article on Aristarchus of Samos, and the section about heliocentrism deeply puzzled me:
(BTW, does anybody know how to quote Wikipedia easily?)
Aristarchus suspected the stars were other suns^[3] that are very far away, and that in consequence there was no observable parallax, that is, a movement of the stars relative to each other as the Earth moves around the Sun. The stars are much farther away than was generally assumed in ancient times; and since stellar parallax is only detectable with telescopes, his speculation although accurate was unprovable at the time.
The geocentric model was consistent with planetary parallax and was assumed to be the reason why no stellar parallax was observed. As known, Ptolemy later preferred the geocentric model which was held for true during the Middle Age.
A demonstration of Aristarchus' heliocentric model was given by Seleucus of Seleucia, a Hellenistic astronomer who lived a century after Aristarchus.^[4] The fact that Pliny the Elder^[5] and Seneca^[6] still referred to planets' retrograde motion as an apparent phenomenon, suggests that heliocentrism was an accepted theory still by their times.
It is a common idea that the heliocentric view was rejected by the contemporaries of Aristarchus. This is due to Gilles Ménage's translation of a passage from Plutarch's On the Apparent Face in the Orb of the Moon. Plutarch reported that Cleanthes (a contemporary of Aristarchus and head of the Stoics) as a worshipper of the Sun and opponent to the heliocentric model, was jokingly told by Aristarchus that he should be charged of impiety. Gilles Ménage, shortly after the trials of Galileo and Giordano Bruno, amended an accusative with a nominative, and vice versa, so that the impiety accusation fell over the heliocentric sustainer. The resulting conception of an isolated and persecuted Aristarchus is still transmitted today.^[7]
The heliocentric theory was successfully revived by Copernicus, after which Johannes Kepler described planetary motions with greater accuracy, with Kepler's laws, and Isaac Newton gave a theoretical explanation based on laws of gravitational attraction and dynamics.
[3] Louis Strous. "Who discovered that the Sun was a star?". solar-center.stanford.edu. Retrieved 2014-07-13.
[4] Plutarch, Platonicae quaestiones, VIII, i
[5] Naturalis historia, II, 70
[6] Naturales quaestiones, VII, xxv, 6–7
[7] Lucio Russo, Silvio M. Medaglia, Sulla presunta accusa di empietà ad Aristarco di Samo, in "Quaderni urbinati di cultura classica", n.s. 53 (82) (1996), pp. 113–121
I have the the following questions about its History:
The "A demonstration of Aristarchus' heliocentric model was given by Seleucus of Seleucia" period sounds to me bollocks. At best, from what I get Plutarch might have told us that he thought he had given one, which is completely different. I am studying physics, and from my readings about the History of Science it is quite clear to me that the Greeks had just no way to prove heliocentrism, the main problems being lack of parallax and the impossibility with their instruments of explaining the lack of dynamical effects from the supposed Earth's non-inertial reference frame (using a modern language). Is it right?
PARTIALLY OT - I once read somewhere that the some Greek had already anticipated the "Stars would be too big" counter-argument from Tycho to "They might be just too far for parallax", but I don't remember where and I have no source, does anybody know if it is true or am I just imagining things?
The article gives the impression that heliocentrism was actually some sort of a standard model of cosmology in ancient times, until those bad, bad Dark Ages came. To my inexpert knowledge, this is false and would have been simply bizarre, since geomobility solved no problem (cinematically speaking everything was equivalent) and introduced many (again, parallax and dynamics, and it helps that no mention of the rationale for Ptolemy's choice is done in the article). Am I wrong?
It gives such impression by arguing on primary sources by Pliny the Elder and Seneca (something that as far as I know should be prohibited as hell on W) which I don't know much about, can anybody expand on them?
Saying that Aristarchus theory was "revived" by Copernicus looks to me quite a stretch, but this is just nitpicking.
The first of the few secondary sources used by the article, and the only one in the summary, is the infamous "History of the Conflict Between Religion and Science" by Draper. This actually explains much.
My experience with Wikipedia is pretty much limited to having myself kicked out of my language's version after a series of heated discussions with an administrator on Giordano Bruno, Galileo and Tycho (with it's salient points being him adding to some articles a whole lot of arguing on primary sources to prove that Galileo knew that stars were point like, ignoring my peer review sources and substituting my sources on Giordano Bruno unscientific approach from Jole Shackelford, Ronald L. Numbers, Angelo Mercati, Frances Yales and Richard Olson with... a quote by Stephen Hawking), my knowledge on the subject is limited and I might be not the best diplomat, so I think I won't do anything about it.
However, I believe such inaccuracies are deeply worrisome. Wikipedia is, sadly, the main source of "knowledge" for a lot of people, and as far as I know such articles only contribute to the propagating of myths.
The "A demonstration of Aristarchus' heliocentric model was given by Seleucus of Seleucia" period sounds to me bollocks. At best, from what I get Plutarch might have told us that he thought he had given one , which is completely different.
You're exactly right. The following passage from Neugebauer's History of Ancient Mathematical Astronomy (1975) will probably help clear things up. Page 697:
Much discussion has been caused by another remark of Plutarch^27 which Heath renders as follows^(28): "...the earth... was not represented as being... at rest, but turning and revolving, as Aristarchus and Seleucus^29 afterwards maintained (apedeiknusan) that it did, the former stating this only as a hypothesis, the latter as a definite opinion (apophainomenos)." The last verb has a wide range of meanings, from "declare", "proclaim", to "prove". Van der Waerden insists that only the strictest meaning, i.e. "to prove", should be accepted^30 and he even suggested that this implies that Seleucus (or an otherwise unknown pupil of his) computed heliocentric planetary tables.^31
^27 Plutarch, Plat. Quaest. 1006 C (ed. Hubert, Moralia VI, 1, p. 129, 21-25).
^28 Heath, Aristarchus, p. 305.
^29 On Seleucus (ca. 170 B.C.) cf. above p. 610f.
^30 Van der Waerden [1970, 1], p. 6, p. 11. Ironically he mixed up the two verbs in question: he says that apodeiknumi must mean here "to prove" but he himself renders it by "sich vorstellen" whereas the crucial term is apophainomai about which he has nothing to say.
^31 Van der Waerden [1970, 1], p. 7, p. 51. Needless to say such tables would be useless for a terrestrial observer.
Neugebauer goes on to mention a fragment of Seleucus' work found in an Arabic text dating to ca. 900 CE which shows that Seleucus' method was not empirical or mathematical, but entirely driven by philosophical assumptions. So he certainly didn't "prove" or "demonstrate" anything. He did however develop a lunar theory of tides, and observed the relative regularity of the tides at the equinoxes (see Strabo 3.5.9) and linked this to Aristarchus' theory, arguing that both the sun and moon contributed to the tides. He was no idiot, but he certainly wasn't a scientist.
Aristarchus may not have been such a great observer himself. One snippet preserved about his treatise On the sizes and distances of the sun and moon tells us that he measured the sun's apparent diameter as 2 degrees of arc, whereas in fact it's half a degree. Criticising him for this might be a bit harsh though. -- retracted: see follow-up post.
I once read somewhere that the some Greek had already anticipated the "Stars would be too big" counter-argument from Tycho[3] to "They might be just too far for parallax", but I don't remember where and I have no source
That was Aristarchus. The source for this is Archimedes, whose Sand-reckoner mentions that in Aristarchus' theory the size of the earth's orbit around the sun was negligible compared to the size of the sphere of fixed stars.
The article gives the impression that heliocentrism was actually some sort of a standard model of cosmology in ancient times, until those bad, bad Dark Ages came. To my inexpert knowledge, this is false and would have been simply bizarre,
Again right. Seleucus is the only named astronomer/astrologer we know of who adopted Aristarchus' theory. There were others -- Sextus Empiricus Against the mathematikoi 10.174 refers to "Aristarchos and his supporters" -- but Seleucus is the only other real heliocentrist whose name survives. Other astronomers didn't exactly ridicule the theory (except for one Cleanthes, who wrote a vitriolic tract against him), but they did reject it because of its gross predictive inadequacies, which were caused by Aristarchus' assuming circular planetary orbits (and of course Copernicus wasn't immune to this fault either).
It gives such impression by arguing on primary sources by Pliny the Elder and Seneca (something that as far as I know should be prohibited as hell on W)
I don't know what W is, and there's too much Pliny and Seneca to guess which passages these might be. If you can give the references in Pliny and Seneca it'd be possible to look them up -- though I don't for a moment imagine there's nothing to see there.
Saying that Aristarchus theory was "revived" by Copernicus looks to me quite a stretch, but this is just nitpicking.
Copernicus did credit Aristarchus with the theory in his manuscript of De revolutionibus, but he reportedly removed the passage in the printed version. He originally wrote
Credibile est hisce similibusque causis Philolaum mobilitatem terrae sensisse, quod etiam nonnulli Aristarchum Samium ferunt in eadem fuisse sententia...
It is plausible that for similar reasons to these Philolaus perceived the motion of the earth, since some say that Aristarchus of Samos was of the same opinion...
(I'm having to take the source in my link, above, at its word: I can't find any passage corresponding to this in the printed edition of De revolutionibus. The only mention of Philolaus is in Book 1 ch. 5, page 3b. The book linked above goes on to suggest that Copernicus might have had access to a manuscript of Aristarchus' Archimedes' Sand-reckoner, which gives the fullest account of Aristarchus' theory; it wasn't published in print until 1544, a year after De revolutionibus and Copernicus' death.)
(Philolaus also believed that the earth moved, but he wasn't a heliocentrist: he was a Pythagorean who believed that the entire universe, including the sun, rotated around something that called "the central fire", which appears to be something more closer to the elements imagined by the pre-Socratics than to anything physical.)
The first of the few secondary sources used by the article, and the only one in the summary, is the infamous "History of the Conflict Between Religion and Science" by Draper. This actually explains much.
I'd agree with that. Go read Neugebauer instead!