One of the standard stories that gets wheeled out every time that some ahistorical fan of Galileo wishes to prove that the rejection of the heliocentric hypothesis at the beginning of the seventeenth century was purely based on dogmatic religious ignorance and had no objective basis in fact is the case of the professor of philosophy who refused to even look through Galileo’s telescope, rejecting his astronomical findings out of hand. Even if this story was true, as it stands in the simplistic version sketched above, it use in this context is questionable to say the least. Supporters of science contra pseudo-science, and they are the ones most likely to quote the story, have a mantra that in one version reads, “The plural of anecdote is not data”. They, quite rightly, reject the presentation of anecdotes as scientific evidence but are quite prepared to base their interpretation of the history of science on an anecdote; not exactly what one would call consistency. Even if twenty North Italian professors of philosophy had refused to look through Galileo’s telescope, rather than one, it would still tell us nothing about the epistemological status of the heliocentric hypothesis in 1610 or the grounds for its rejection by the majority of those qualified to judge. However the story has an even more interesting status as historical evidence because although true, it is, as usually related, a myth.
The standard version presents Galileo as the visionary apostle of modern science and the refusnik as a bigoted ignoramus. This picture is far from the truth; Galileo and his opponent in this case were best friends and the true story reveals several very important aspects of the early use of telescopes and the scientific problems that the first telescopic discoveries generated.
The professor in question was Cesare Cremonini (1550 – 1631) who was appointed to teach at the University of Padua shortly before Galileo and both of them belonged to the same clique of polymath, rebellious intellectuals in the Venetian State that include Paolo Sarpi amongst others. Cremonini was a hard-core supporter of the philosophy of Aristotle and thus Galileo’s natural opponent and the two indulged in good natured and usually humorous sparring matches, often for the entertainment of their mutual friends. Cremonini was also a permanent object of investigation of the Inquisition because he rejected the Church’s Thomist interpretation of Aristotle preferring his Peripatetic Philosophy pure. He was thought, following Aristotle, to believe in an eternal universe without creation and the mortality of the human soul, which did not endear him to the Church. Although radical in his views and highly argumentative he did not disparage his opponents, he wrote in his book on cosmology, De Caeolo (1613):
Disagreement about learned matters does not make enemies of honourable men, rather, it is a sign of great ignorance to dislike people who do not accept your opinion. [a dictum that many users of the Internet could take to heart]
In fact it was the writing of this book that led to the infamous telescopic rejection incident. A mutual friend, Gualdo, wrote to Galileo saying that Cremonini was planning on writing a book, De Caeolo, against him. Galileo replied feigning trepidation to which Cremonini responded that Galileo need not worry, as he wasn’t going to mention him or his discoveries in his book. It was within this exchange of friendly banter between three friends that Cremonini stated that he didn’t trust telescopes because when he looked through them they confused him and made him dizzy. He inferred that only people with quirky eyesight and unrestrained imagination could see what Galileo had claimed to see. It should be noted that it was well known that Galileo did indeed have ‘quirky’ eyesight.
Most authors retelling the story[1] completely ignore the context and even ignore the fact that Cremonini had actually looked through telescopes and those that mention his claim that it made him dizzy do so as if Cremonini was trying to ridicule the telescope and its users. There is another more rational explanation, Cremonini was simply telling the truth.
The early telescopes were to put it mildly very primitive. They suffered from spherical and chromatic aberration, had a very narrow field of view and the glass out of which the lenses were made was of very poor quality often leading to extreme distortion of the images viewed. One early user described the stars that he saw as rectangular in form, very blurred and fringed with colours. It is actually highly probable that Cremonini genuinely had negative experiences using telescopes.
In his exchanges with Galileo Cremonini had another much more serious reason for rejecting Galileo’s telescopic discoveries. He argued, quite correctly, that if the moon was really a large lump of rock as Galileo claimed then he, Galileo, would have to develop a new physics to explain why the moon didn’t fall on the earth. He Cremonini would wait until that new physics existed before accepting Galileo’s discoveries. Galileo was of course very much aware of this central problem in his cosmology and in fact devoted most of his scientific activity in trying to solve it. As I have commented on more than one occasion on this blog this was in fact the central reason why heliocentricity could not be accepted until the end of the seventeenth century; a century that was scientifically devoted to creating that necessary new physics.
I think that what this comparatively trivial story from the early stages of the acceptance of a heliocentric world view teaches us is that often repeated simplistic stories from the history of science often take on a completely different meaning when told in full and in context.
[1] My version is based on that recounted by John L. Heilbron in his Galileo, OUP, 2010
The Renaissance Mathematicus 
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I really enjoy reading your blog thanks for sharing your point of views.
Those simplistic stories, as far as I know, were mostly invented during the XIX, to serve a purpose of that century. Like in France, in the line of Positivism to show the superiority of the so called scientific method to any other form of knowledge and to help in the political fight against the omnipotent Catholic Church at a time where the political mantra was to separate State and Church. Political transition that started during the XIX to end up beginning of XX (if one considers that is a finished process in western Europe, it seems to be fairly finished in France). That brings us to the question: when will we really get out of the XIX century?
José, what you say is very correct. Most of the myths of science that are still current today were created/invented in the late eighteenth or in the nineteenth centuries.
What I find particularly annoying are the modern popular books that list the academic books and papers in their bibliographies of the last fifty to sixty years debunking those myths but still perpetuate those myths in their own texts.
Thony, This is great work, You exemplify what high quality science history is all about. Always a pleasure reading your blog.
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Very nice.
I sometimes wonder if these legends are still told because they allow
complex and difficult social negotiations to be conducted in a coded and safe way that avoids full on confrontation and dissent.
Peasant marriage negotiations are the classic (possibility of open violence if it all goes wrong) so its was conducted in terms of \”I hear you have a ship without a rudder\”, \”A ewe about to leave the fold\” etc.
When you mentioned the fact papers were read but myths are used. Reminded me of fieldwork I did on the evil eye. Found to my surprise that some folk expressing at length the belief that a member of the community could predict or cause death or misfortune were atheists and appeared to have little or often no belief in the supernatural.
It was an accepted and traditional way for them to discuss complex group relationships and assert social position in a dynamic and fluid social situation in an indirect way that avoids serious dispute.
If science \’myths\’ are playing this role exposing the history is great from a historical perspective but from a \’myth busting\’ one (I think I prefer the term ethnography here and understanding to busting) the important context is contemporary although it may have past historical form its not simply passive repetition.
p.s Getting somewhat spoiled at the moment with H.O.S blogging. I read a wonderful blog post on the republican rape issue at the Guardian, did not bother to name check but was surprised by how good it was; so was unaware until I read G.S. carnival who one half of the team was.
This was as pleasurable. Interesting times!
Tsk, tsk … once again making Life, the Universe and Everything complicated for those who just want a nice, neat, simple narrative that fits comfortably with their preexisting beliefs! Don’t you know that you are only supposed to do that to theists and creationists?
Not 42 it’s 43!
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It reminds me of Angevin hagiography and the issues of studying this subject, as it is only recently that attention is being given to some of the material. A number of important sources have been until recently more or less ignored leaving research woefully inadequate and only now being started.
The standard approach was to attempt to extract from the vitae evidence for the earlier periods the texts discussed. Historians would then get rather annoyed at the romance rather than history the scribes wrote and the seriously deficient historical nature of the writers of these “secondary sources” (many were using lost material and had access to important monastic libraries.
Move to look at these works firmly in context and to view them as part of the religious, cultural and political contexts in which they were actually written is the focus of recent attention.
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au contraire..
Cremonini presumed without evidence that Galileo’s telescope was as faulty as previous examples. If theory about heliocentricity was lacking, then Cremonini wasn’t about to let facts change anything. The anecdote lives.
“Cremonini presumed without evidence that Galileo’s telescope was as faulty as previous examples”
Which it was
On the other hand, as you have also remarked many times on this blog, the roots of this new physics go back at least to the 14th C. Oxford calculators, and also the 14th C. Buridan, and before them the 6th C. Philoponus.
Which is not to deny that the situation in the 16th C. was equivocal. Cremonini’s position was quite reasonable. But if the evidence wasn’t solidly on the side of a moving Earth, neither was it solidly on the other side.
Although, unfortunately, it is behind a paywall, the paper “Telescopes of Galileo” by V. Greco et al in Applied Optics Vol 32, No 31, pp6219-6226 (1993) does show interferograms of the actual lenses in Galileo’s telescope. The first paragraph of their conclusions states:
“A series of optical measurements has been carried out on the telescopes of Galileo. It has been found in particular that such instruments allow for nearly diffraction-limited imagery at a single wavelength. This high-quality feature resulted from Galileo selecting the best part of the objective lens with properly sized and shaped apertures. The assessment criterion is such that the residual imperfections are smaller than the chromatic aberration effects. The latter appear to be the real limit on the performance
of the telescopes of Galileo.”