A strange defence

This week saw the broadcast of the first episode of the remake of the legendary television series COSMOS, originally hosted by Carl Sagan and now being presented by Neil deGasse Tyson. Although I have now had the chance to view it thanks to the good offices of the man for all things Darwinian, Michael Barton (@darwinsbulldog), I’m not going to blog about it as Tim O’Neill, Renaissance Mathematicus reader and commentator, and fellow invincible warrior in the struggle against bad history of science,  is writing a guest post on the subject, which if all goes well will appear here on next Monday. However this post is directly concerned with one part of the show.

The centrepiece of the episode was an anime style carton on the life and thoughts of infamous Renaissance heretic Giordano Bruno. This immediately led to a raising chorus of voices on Twitter wondering what my views on this would be. Having in the mean time seen it I labelled it on Twitter an “Anime Draper-White for the Twenty-First Century”. For anybody who doesn’t know John William Draper (1811 – 1882) and Andrew Dickson White (1832 – 1918) are the two nineteenth century American academics who created the myth of a war (their term) between science and religion. A myth still unfortunately believed in by many a gnu atheist.  I’m not going to say anything more about this unfortunate piece of animated bollocks, as I’m sure that Tim will comment extensively in his guest post.

However the rest of the Intertubes has not remained silent on the issue and I can recommend the eminently sensible post on the subject by Meg Rosenburg (@trueanomalies) and the wonderfully provocative post by Becky Ferreira (@beckyferreira) “What ‘cosmos’ got wrong about Giordano Bruno, the heretic scientist, which contains the absolutely brilliant description of Bruno: “Bruno was a walking, talking shit storm, with a black belt in burning bridges”.  How I wish that I had coined that sentence!

The debate continued at Discovery Magazine with a blog post by Cory S. Powell, “Did “Cosmos” pick the wrong hero?”, in which Powell suggests that Thomas Digges would have made a better subject for the cartoon than Bruno. Personally I side with Meg Rosenburg who asks whether we need any heroes at all when discussing the history of science; a rhetorical question to which the answer is no.

Powell’s post finally provoked a response from the makers of “Cosmos” in the form of a post by Steven Soter, astrophysicist and co-writer of “Cosmos”, titled The Cosmos of Giordano Bruno (now with added response from Powell) and it is to this post that I now wish to reply, as it contains a number of very questionable statements.

In his second paragraph Soter writes the following:

Powell’s critique dwells on the well-known facts that Bruno was a mystic and an extremely difficult person. Well, so was Isaac Newton, who devoted as much time to alchemy and biblical numerology as to physics. But that has no bearing whatever on his good ideas.

I could write a whole post just about this one paragraph. First off Soter is putting Bruno a man who had one half correct cosmological idea during an intoxicating religious fantasy, that makes you wonder if he’d been hitting the magic mushrooms, with Isaac Newton who produced some of the most important new mathematics, astronomy, and mathematical physics in the history of mankind. That’s one hell of a lopsided analogy Mr Soter! Secondly as anybody knows, who is up to date on his Newton research, or who has simply read some of my blog posts on the man, Newton’s theology and his alchemy did have a massive bearing on his ‘good ideas’.

Soter then corrects Powell as to who first claimed that the universe was infinite, which to be fair Powell got wrong, although neither of them remarks that Lucretius, Bruno’s source, didn’t think of this himself but actually got the idea from the Greek atomists.

We now come to the core of the matter and the reason why Soter et al claim to have included the Bruno cartoon in their show:

Bruno’s originality lies elsewhere. He was indisputably the first person to grasp that the Sun is a star and the stars are other suns with their own planets. That is arguably the greatest idea in the history of astronomy. Before Bruno, none of the other Copernicans ever imagined it.

Leaving aside the hyperbole about ‘the greatest idea in the history of astronomy’, as he says the question is highly debateable, this paragraph still has several issues. Firstly the Greek philosopher Anaxagoras had already suggested that the sun and the stars were one and the same in the fifth century BCE, although he didn’t hypothesise the presence of other planets. Secondly if this was the real reason for including the Bruno cartoon in this episode, why was the main emphasis of the cartoon placed on the Church’s treatment of Bruno as a heretic even to the extent of presenting the Church officials as demons with red glowing eyes, I smell a rat.

If you think I’m misinterpreting the message of the cartoon I offer this comment from Meg Roserburg’s post, Albeit says:

No offense, but I think you’re missing the point here. The moral of the story, as stated in Cosmos, is: don’t let your beliefs stand in the path of reality. Bruno’s necessarily oversimplified story is just a warning about anti-science and dogmatic thinking.

Throughout the Internet you can find similar interpretations, so either the message of the cartoon was other than claimed by Soter or they really made a balls up of scripting it.

Soter than attacks Powell’s suggestion that Thomas Digges should have been featured rather than Bruno, after all he did suggest that the universe is infinite before Bruno. Soter’s argument is a little strange he writes:

But Digges regarded the stars as “the court of the celestial angels” not as the suns of other material earths. And that was a big step backwards. In contrast, Bruno wrote, “the composition of our own stars and world is the same as that as many other stars and worlds as we can see.” His profound intuition had to wait three centuries to be verified by the spectroscope.

First off Digges’ claim that the stars were the court of the celestial angels is just bog standard medieval cosmology, so in that sense is not a step backwards. Secondly Digges wrote and published earlier than Bruno, so in that sense it is also not a step backwards.

That the composition of everything in the cosmos was the same is neither new nor original to Bruno. The Stoics had believed this in antiquity and there had been a major revival in Stoic scientific philosophy in the sixteenth century making Bruno considerably less original on this count than Soter would like to see him.

Soter is also guilty here of quote mining, selecting those parts of Bruno’s fantasy that fit with our modern concepts and quietly ignoring those that don’t. This is a form of presentism known as searching for predecessors. One takes an accepted scientific idea and filters through history to see if somebody had the same idea earlier, then crying eureka and declaring the discovered thinker to be a genius ahead of his or her times. This activity can best be observed in popular histories of atomism where everybody who ever believed that matter consists of some sort of particles are all swept up into one glorious heap and declared to be predecessors of John Dalton. In Bruno’s case one has to ignore the rather inconvenient fact that he thought that the whole of space was filled with identical solar systems placed throughout space at equal intervals, a conception that doesn’t quite fit with our actually understanding of the universe.

Soter now attacks Powell for saying that neither Kepler nor Galileo thought much of Bruno. Soter mocks and ridicules Kepler for believing in a finite universe.  This is ironic given that Soter thinks it is irrelevant that Bruno produced fifty tons of shit including rejecting the use of mathematics in science because he produced one tiny little diamond of thought.

Soter then quote mines again making Kepler to a supporter of Bruno. He correctly quotes a passage from Kepler’s Dissertatio cum Nuncio Sidereo (1610) his response to Galileo’s telescopic discoveries.

What other conclusion shall we draw from this difference, Galileo, than that the fixed stars generate their lights from within, whereas the planets, being opaque, are illuminated from without; that is, to use Bruno’s terms, the former are suns, the latter, moons or planets?”

Here Kepler is referring to the difference in the images of planets and stars when viewed through the new invention the telescope. Kepler would here be appearing to support Bruno’s theory and that is the impression that Soter wisher the reader to have but this is actually an illusion. Kepler says let us use Bruno’s term, he doesn’t say let us adopt Bruno’s theory. You might think I’m splitting hairs and that by adopting Bruno’s term Kepler is of course adopting Bruno’s theory but this is very definitely not the case. How can I be so sure? Because Kepler himself tells us so, he does so by evoking what is now known as Olbers’ paradox.  Kepler argues, as did Heinrich Olbers, a German astronomer, in the nineteenth century, that if the heavens were filled with an infinity of suns equally distributed in all direction, as Bruno claimed, then there would never be a night, these suns lighting up the skies twenty-four hours a day. His, incorrect but rational solution, to the paradox was that the Sun and the stars are fundamentally different and thus Bruno was wrong. Far from being a tacit supporter of Bruno’s hypothesis, as Soter would have us believe, Kepler actually refuted it with a good solid, if incorrect, scientific argument. A further irony in this situation is that Kepler was not the first to realise that an infinity of suns would lead to Olbers’ paradox, thus seeming to invalidate Bruno’s hypothesis, Thomas Digges, who hypothesised an infinity of stars before Bruno, also explicitly recognised the problem.

Having abused Kepler Soter now moves on to Galileo accusing him of plagiarism and cowardice, in the process again making a false claim:

Galileo never once mentioned Bruno’s name. Of course in the land of the Inquisition he had good reasons. But in his “Dialogue on the Two Chief World Systems” (the book that got him into deep trouble), he discretely accepted Bruno’s greatest idea, writing that the fixed stars are other suns.

Don’t let anybody tell you that being a pedantic history of science blogger is an easy life. Although I possess two different translations of Galileo’s magnum opus I don’t know it off by heart and was not aware of Galileo “discretely accepting Bruno’s greatest idea”, so I spent about four hours yesterday evening going through every single reference to star, stars or sun listed in the index to the Drake translation comparing with the Finocchiaro translation and searching for further information in five volumes of secondary literature. The only consolation for all of this effort was that I found the passage to which Soter is probably referring. On The Second Day in a discussion on the movement of the heavenly bodies Salviati makes the following observation:

Now behold how nature, favoring our needs and wishes, presents us with two striking conditions no less different than motion and rest; they are lightness and darkness – that is, being brilliant by nature or being obscure and totally lacking in light. Therefore bodies shining with internal and external splendour are very different in nature from bodies deprived of all light. Now the earth is deprived of light; more splendid in itself is the sun, and the fixed stars are no less so. The six moving planets entirely lack light, like the earth; therefore their essence resembles the earth and differs from the sun and the fixed stars: Hence the earth moves and the sun and the stellar sphere are motionless.

This passage is, like the Kepler quote above, very clearly based on Galileo’s telescopic observations of the stars and planet and their respective telescopic images and is not borrowed from Bruno. It is also clear that here Galileo is only referring to the stars and the sun both being self-illuminating, his discussion only treats of one attribute, lightness or darkness, but he doesn’t take the next step of saying that therefore they are the same. He might possibly have thought so but then again he might not. It is also clear here that with his reference to the stellar sphere Galileo s still accepting a traditional bounded finite cosmos.

I now turn to the implicit argument that Galileo didn’t reference Bruno because of the Inquisition, either through caution or, as I provocatively said above, through cowardice. This argument is not unique to Soter but has been used by numerous commentators in the Internet in the last few days. In the Roman Inquisition had, like the FBI, had a Most Wanted list, then during the first part of Galileo’s life Numero Uno on that list would have, without any doubt, been the Servite monk Paolo Sarpi (1552 – 1623).  To quote John Heilbron’s Galileo biography, “…the Servite Sarpi, would present the Vatican with a graver threat than Bruno”. During his years in the Republic of Venice, as professor of mathematics at the University of Padua, Galileo’s best mate and intellectual sparing partner was Sarpi, a fact that was publically well known. Unlike Bruno, who they regarded as a nuisance, the Venetian authorities, who were very proud of their intellectual rebel, Sarpi, who was Venetian born and bred, refused to deliver him to the Roman Inquisitions. Making him even more of a thorn in the side of the Church. Galileo’s close friendship to Sarpi was far more dangerous to his relations with the Church than any casual scientific reference to Bruno would have been. Galileo did not quote Bruno because he didn’t want to, not because he was scared of the Inquisition.

It is worth noting in this context that when Galileo applied for and was granted the position of court philosophicus and mathematicus to the Medici in Florence his Sarpian friends in Venice warned him against leaving the comparatively safe haven of thr Republic, where he was free to think and say almost anything he liked, for the shark infested waters of court intrigue and religious orthodoxy of Florence and Rome. However fame, fortune and social status were more important to Galileo than freedom of thought and speech so he ignored his friends’ warnings with the well known historical consequences.

To close this already over long post I would like to address a historiographical point related to Soter’s deification of Bruno in the history of science. Wirkungsgeschichte is a German term that refers to the historical impact of a scientific theory, invention, or discovery. Some ideas make little or no impact and disappear from the historical stage requiring them to be rediscovered at a later date. A classic example of this is the correct explanation of the cause of the rainbow. Theodoric of Freiberg discovered the correct explanation through empirical experiments in the thirteenth century. However his discovery had almost no impact and got lost, meaning that it wasn’t until the seventeenth century, when Descartes rediscovered it, that the correct explanation of the rainbow became generally known. Bruno’s lucky guess that the stars are suns or that the sun is a star had almost no impact and was largely ignored and forgotten. This makes him in a historical sense a dubious figure to elevate to the status of a scientific hero, as Soter apparently wished to do with his very strange animation in the COSMOS broadcast.