Looking twice at the history of science

Wednesday, March 6, 2013

13 things Gopnik got right about Galileo

Since you are reading this, you have probably read Adam Gopnik's recent essay-review about Galileo Galilei in The New Yorker. You might also have seen some reactions from unimpressed historians, one of whom calls the article “extremely pernicious.” I think that some of Gopnik's errors have been exaggerated, and that most of his felicities have gone unnoticed. The moral is that us historians should be as alert to what popular writers get right as we are to what they get wrong. After all, we can hardly criticise Gopnik for imbalance in his treatment of Galileo if we are imbalanced in our treatment of Gopnik. Expand post.


  1. Moreover, Gopnik suggests that he went wrong about the tides precisely because of the skepticism that makes him seem modern (shades of Paul Feyerabend?).

    In this point I think Gopnik is seriously wrong. There was, as Galileo well knew, very solid empirical evidence for a luna tide theory and even more solid empirical evidence that refuted his own mechanical dynamic tide theory.

    He didn't reject the luna tide theory through scepticism but because his own tide theory was the only 'proof' that he had for heliocentricity. This 'proof' was the central point of his book and in fact the book was supposed to be titled Theory of the Tides until the Vatical told him not to.

    If he had abandoned his theory for the much more rational luna influence theory then he might as well have abandoned his book and never written it.

    1. Hi thonyc, and thanks for your comment.

      Are you saying that Galileo was entirely insincere in putting forward the tidal theory as proof of heliocentricity? If he placed so much weight on the theory, and held it for so long (Heilbron suggests that it sealed his commitment to Copernicanism as early as 1595) surely he thought it had at least something in its favour? And isn't it reasonable to take Galileo at his word when he wrote near the end of DTWS that Kepler "lent his ear and his assent to the moon's dominion over the waters, to occult properties, and to such peurilities"?

      Perhaps "skepticism" is too general a term. What Gopnik meant, I think, is that Galileo rejected the "moon's dominion over the waters" in the same spirit as today's self-described skeptics reject things like extra-sensory perception--namely that there is no known, transparent mechanism by which these phenomena could occur. My point in the above post was that Gopnik seemed perfectly aware of the irony that this insistence on intelligible causes, though it seems very modern, led Galileo astray.

      But suppose you are right, and Galileo stuck with the tidal theory out of sheer dogmatism or self-preservation, and that his complaint about "occult properties" was a bluff. That means that Gopnik has overstated the Feyerabendian thesis that apparently rational methods (like insisting on intelligible causes) can lead to wrong results. But historians of science usually consider this quite a radical, sophisticated thesis that many popular writers have not grasped yet. So we should be pleased that a popular writer has not only grasped a radical point, but pushed it even further than the evidence allows!

    2. I'd like to echo Michael Bycroft's question, do you believe that Galileo was insincere? I've always felt that a combination of wishful thinking and unclear physics lead to Galileo's solid belief in the theory.

  2. Three things struck me unfavorably in Gopnik's article:

    (1) His early statement:

    And the best argument, often the only argument, for all these beliefs was that Aristotle had said so, and who were you to say otherwise?

    This sums up a paragraph that sets up a black-hat/white-hat, pigheaded-old-fogies vs. innovative-new-thinkers opposition, one which (as I understand it) is a serious misreading of the intellectual history, misrepresenting both Galileo's contemporaries and Galileo himself.

    (2) The Chinese Communist Party comparison:

    The Catholic Church in Italy then was very much like the Communist Party in China now: an institution in which few of the rulers took their own ideology seriously....

    I wish he had stated more clearly what he meant by 'ideology'. Since I thought it too absurd to think that the Catholic hierarchy were all secret atheists, I assumed he meant they were all secret Copernicans. I believe Gopnik never really grasped the point that a scientifically sophisticated 17C. intellectual could disbelieve in Copernicanism. (I also wonder on what evidence Gopnik is so sure about the private beliefs of the CCP.)

    (3) His statement, near the end of the essay, that

    [Mayer's] argument is basically one of those “If you put it in context, threatening people with hideous torture in order to get them to shut up about their ideas was just one of the ways they did things then” efforts, much loved by contemporary historians.

    My knowledge of Mayer's work is pretty much the same as yours (plus his article "The censoring of Galileo’s Sunspot Letters and the first phase of his trial".) I suspect though that Gopnik wanted Mayer to express a strong value judgement.

    You've discussed the pros and cons of anti-presentism (or anti-Whiggism) extensively on this blog. Using your classification (from "Different kinds of Whig history..."), Gopnik appears to have fallen prey to the fixed-evidence fallacy, and some aspects of dogmatic side-taking ("black hat v. white hat").

    I have no problem with Gopnik taking sides in the Church-Galilo conflict based on ahistorical free-speech values, provided that he appreciates why a professional historian, like Mayer, might want to maintain a more value-neutral stance. (Also of course that Gopnik himself realize how ahistorical such a value judgement is --- I'm not convinced that he does.)

    Finally, how much of a pass should we give Gopnik because he's not a professional? The New Yorker prides itself for its fanatical fact-checking, and for its long-form essays that delve into levels of nuance not available in most other magazines. I grant your good points, but they are the least I would have expected of this writer in this venue.

    1. Thanks for this thought-provoking comment. I'll go through your numbers.

      (1) Reading it again, I agree that the statement you quote is a "serious misreading of the intellectual history."

      I guess this comes under my point eight in the above post, where I noted that "Gopnik does not mention that Galileo overstated the case for Copernicanism." To be clear, I should have added that he also understated the case against.

      (Although it would be unfair not to add that some of Galileo's opponents really were "pigheaded-old-fogies", that it was not long after Galileo's death that Copernicanism gained wide acceptance among leading astronomers, and that this acceptance was partly due to Galileo's discoveries and arguments).

      (2) I think that what Gopnik got right with his Communism/Catholicism analogy was a) the Church could tolerate lots of valuable Copernican science as long as the scientists treated Copernicanism as a hypothesis, and b) the Church was especially sensitive to threats to its power.

      In exchange for these points, I'm willing to forgive Gopnik the disanalogies between the Church and Communism.

      I'll also forgive another point that occurs to me in reading your comment, which is that the Church's "instrumentalism" was still a respectable philosophical position in the 20th century. As you probably know, the great Pierre Duhem argued that astronomical theories--like all scientific theories--should be seen as economical summaries of observed facts, not as claims about the deep structure of the world. The Pope's position on Copernicanism could be seen not as hypocrisy but as a precursor to modern positivism.

      (3) I agree that the statement you quote commits the Whiggish errors you mention (and I'm glad my previous post at helped to identify them!).

      The thing is, there are other parts of the article where Gopnik seems to avoid those errors. For example, in some places he recognises that the fault did not lie entirely with the Church, as when he says that Galileo was "vain."

      I'm going to go out on a limb and say that Gopnik has a point regarding Mayer. I take Gopnik as complaining not that historians want to be value-neutral, but that they move too easily from neutrality to non-neutrality. For example, in the Introduction to his book on the Roman Inquisition Mayer makes it clear that he wants to assess the Inquisition *by the standards of the time.* At the same time, Mayer is quoted in articles where he seems to be saying that Galileo was at fault *by our own standards.* So Mayer seems to have switched from a context-independent judgement ("Galileo's trial was just by 17C standards") from a context-dependent one ("Galileo was at fault, period"). Is this legitimate?

      I hope to say more about this in an upcoming post.

      [4] "how much of a pass should we give Gopnik because he's not a professional?" I think we should at least be *a bit* more tolerant of his errors than we would be of a historian's. Though I take your point that we should be less tolerant of Gopnik writing in The New Yorker than some hack writing in, say, The Sun.

      Maybe you are right, and I went too far in saying that "the pros [of the article] outweigh the cons by a clear margin." But the main point of my post still stands: if we read popular articles with a charitable rather than a critical eye, we may find examples of unexpected historiographical acumen.

  3. Thanks for your response. I pretty much agree with all of it, but it does suggest a couple more points.

    (1) I'd add that it wasn't just more time and familiarity that carried the day for heliocentrism, but also more results: Kepler's Rudolphine Tables, and I believe there was a positive "Coriolis" result (anachronism alert!), obtained by dropping balls from a tower. (Although I can't lay my hands on the exact reference.)

    I wish I knew more about when true heliocentrism -- both dynamic and kinematic, i.e., physical and astronomical -- became the "Standard Model".

    Anyway, it all shows the difficulty of avoiding the fixed-evidence fallacy, or even knowing exactly what the contemporary evidence was. I haven't read Heilbron's book, so I don't know how much Gopnik can be blamed for his unbalanced picture.

    (2) As for instrumentalism, wasn't "saving the phenomena" a common, or even default, position in astronomy back as far as 5C. CE, maybe even back to Plato?

    I can see a family resemblance between positivism and "saving the phenomena", but this needs to be served with a huge helping of anachronism cautions.

    Bruce Stephenson's Kepler's Physical Astronomy (and also Koestler's book) point out how much Kepler's success stemmed from his adoption of a realist position: this was how the planets really moved. Galileo also deserves a lot of (whiggish) kudos for insisting on the reality of the earth's motion. So I'll give Gopnik a plus for making this point.

    (3) I'm not all that familiar with Mayer's work, as I said. Also I speak as a non-historian with an amateur interest. It occurs to me though that your discussion of the Normative Judgement issue in
    Different kinds of Whig history... is on point. In particular:

    The real problem, insofar as it is a problem, is that making normative claims in a work of history is a kind of disciplinary category-mistake. It's like beginning a scientific article with a limerick.

    And having quoted that, I'd like to disagree a bit. As I said in more detail in my comments on Darin Hayton's post, I think this historian's convention is unfortunate. It's too bad that historians don't say up-front, "Here's how I feel about Galileo [or Socrates, or energy, or mono-energism, or whatever]. I've tried to prevent my personal feelings from coloring my historical inquiry. You, the reader, must judge how well I've succeeded."

    1. Thanks for these further comments, and sorry for the belated reply. To your points in (1) I'ld add the detection of the long-sought-after stellar parallax as evidence for the earth's motion. I'm sure historians of astronomy could add many more examples.

      On (2) I'm not enough of a specialist to give a proper answer. I take it that Aristotle's distinction between the sciences of prediction and those of explanation created a natural division between (mathematical) astronomy and (explanatory) cosmology, that this division became a rift as mathematical models of planetary motion became more and more elaborate over the next two millenia or so, and that the realism of Copernicus, Kepler and Galileo was a relatively novel attempt to bridge the gap between the predictive and explanatory parts of what we call "astronomy."

      What I do not know is what were Urban VIII's sources for his arguments against the realist position.

      On (3) I agree that there's something to be said for historians making clear their personal judgement of the past events they discuss (hence my "insofar as it is a problem"). I find that Heilbron does this well in his biography of Galileo, where he unapologetically passes judgement on many of the characters in his story. This makes for a bracing read, but it also helps to explain past events, eg. Heilbron gives Galileo a hard time for the vindictiveness and scientific incompetence of The Assayer, a portrayal that helps us understand why Galileo made so many enemies.

      I'm less sure about whether a reader is better equipped to assess a work of history if they know the personal preferences of the author. This knowledge might help by putting the reader on guard against possible biases in the work, but then again it might cause readers to imagine biases that are not there.

  4. Christopher Graney's paper, "Francesco Ingoli's Essay to Galileo..." arXiv 1211.4244 has useful info about your Urban question.

    Bradley's discovery of the aberration of light (1729) antedated Bessel's discovery of aberration (1838).

    I still think a reader is likely to guess at biases if the author doesn't explicitly state his sympathies, but of course there are dangers with both approaches.