Month: June 2012

Did Anglo-Saxon Chronicle Record Supernova?

Today Nature | News reported on an effort to find evidence in medieval chronicles of a supernova that might account for a spike in carbon-14 levels: “Ancient text gives clue to mysterious radiation spike” (unfortunately, the full article is behind a paywall: “Astronomy: Clue to an ancient cosmic-ray event?”).

A new report in Nature turns to Anglo-Saxon chronicles in searching for evidence of a supernova in A.D. 774.

After hearing about elevated levels of carbon-14 in tree rings in Japan, Jonathan Allen from UC Santa Cruz did some glancing through online transcriptions of medieval chronicles. In an eigth-century Anglo-Saxon chronicle he found a reference to a “red crucifix” that appeared in the sky after sunset (scroll down to A.D. 774). Scientists quoted in the Nature | News report differ in their attitudes toward Allen’s finding. The astronomer seemed convinced
but the physicist was more skeptical. Allen’s own attitude is difficult to judge—the first line of the article suggests that he is cautious.

Caution is probably a good position to hold. Historical chronicles often report various celestial phenomena that seem difficult to interpret. That same chronicle, for example, reports that in 734 the moon appeared as if covered in blood and then in 789: “This year Elwald, king of the Northumbrians, was slain by Siga, on the eleventh day before the calends of October; and a heavenly light was often seen on the spot where he was slain….” Such historical sources are not unproblematic records of observational data that can be mined by 21st-century sciences—we might think we can explain the blood-colored moon but how would we account for the heavenly lights where the king was slain?

We must be careful to avoid cherry-picking bits simply because they confirm our assumptions while dismissing those that contradict our understanding of how nature works.
[Reposted at PACHS.]

The Plague in Oregon

There is little new about the latest reports about a man in Bend, Oregon, suffering from Y. pestis,the dreaded Plague or the Black Death. Plague is endemic in the South West and the West, with cases reported every year since the mid-1950s (see the useful CDC page on plague distribution statistics). Four people in Oregon have suffered from the plague since 1995; this latest case will be the fifth. Today, plague is treated with antibiotics—the victim is being treated with antibiotics and his family members are receiving preventive doses.

Cases of plague in the U.S. since 1900 (Source: CDC: Plague Maps & Statistics)

On some level, any case of plague is cause for concern, but this single case does not seem to warrant raising alarms about a new epidemic or claiming without some qualification that “[s]ome scientists, however, are worried about a resurgence if the plague-causing bacterium develops a resistance to antibiotics, something that seems to already be happening.” This claim is based on a 2007 article at that, in turn, reports on an article from PLoS ONE. Citing earlier work, the PLoS ONE article points to a single case of multiple antimicrobial resistant plague isolated in Madagascar in 1995. This case displayed a “high-level resistance to antimicrobial agents,” that is, to the three drugs recommended for treating plague: streptomycin, tetracycline, and chloramphenicol. In the end, a combination of streptomycin and trimethoprim-sulfamethoxazole (often recommended for prophylactic therapy) proved effective.

In a world concerned with bioterrorism and overseen by Homeland Security, fears of an “aerosolized plague weapon” are predictable as is the “Working Group on Civilian Biodefense.” But even using plague as a weapon is not new. The Soviet Union reportedly stored what they hoped would be weapons-grade plague during the Cold War (the U.S. tried “but couldn’t get the germs to stay virulent”); the Japanese dropped plague infested fleas over China during World War II. And then there is Gabriele de Mussis’s horrific account of the Tartar armies catapulting plague victims into the Genoese city of Caffa on the Black Sea. This is 14th-century biological warfare at its most gruesome:

See how the heathen Tartar races, pouring together from all sides, suddenly invested the city of Caffa and besieged the trapped Christians there for almost three years. There, hemmed in by an immense army, they could hardly draw breath, although food could be shipped in, which offered them some hope. But behold, the whole army was affected by a disease which overran the Tartars and killed thousands upon thousands every day. It was as though arrows were raining down from heaven to strike and crush the Tartars’ arrogance. All medical advice and attention was useless; the Tartars died as soon as the signs of disease appeared on their bodies; swellings in the armpit or groin caused by coagulating humours, followed by a putrid fever.

The dying Tartars, stunned and stupefied by the immensity of the disaster brought about by the disease, and realising that they had no hope of escape, lost interest in the siege. But they ordered corpses to be placed in catapults and lobbed into the city in the hope tha the intolerable stench would kill everyone inside. What seemed like mountains of dead were thrown into the city, and the Christians could not hide or flee or escape from them, although they dumped as many of the bodies as they could in the sea. And soon the rotting corpses tainted the air and poisoned the water supply, and the stench was so overwhelming that hardly one in several thousand was in a position to flee the remains of the Tartar army. Moreover one infected man could carry the poison to others, and infect people and places with the disease by look alone. No one knew, or could discover, a means of defence.

Today, you are much more likely to contract the plague through contact with infected rodents, in other words, through your own carelessness. As Emilio DeBess, Oregon’s public health veterinarian, pointed out: “Taking a mouse out of a cat’s mouth is probably not a good idea.”

[A note on terminology: the term Black Death was coined in the early modern period, perhaps as early as the mid-16th century, but did not become widely used until the 19th century after the publication of I.F.C. Hecker’s The Black Death in the Fourteenth Century. And it is not clear that the term was meant to describe the plague’s “blackening effect on infected skin.”]

Lynn White—Medievalist and Futurist?

Lynn White focused on the role of technology in the middle ages searching for the roots of the technological innovation that contributed to the West’s rise and technological supremacy. His Medieval Technology and Social Change is a collection of lectures delivered in 1957 and remains an important book, which coincidentally was published the same year as Thomas Kuhn’s The Structure of Scientific Revolutions. His “The Historical Roots of Our Ecologic Crisis,” Science 155 (March 10, 1967) still attracts attention and comment. White was a founding member and president of the Society for the History of Technology and president of the History of Science Society. Candace Barrington wrote a nice entry on White in the new Handbook of Medieval Studies (De Gruyter, 2010). While an expert on medieval technology

Lynn White’s comments to McCall’s on what the future holds.

Despite being known for his work on riding stirrups and feudalism, and his work on windmills and sources of industrial power in the middle ages, White was apparently something of a futurist. In 1968 the American women’s magazine McCall’s asked White to predict what marriage, sex, and the family would be like in 2001. White seems to see a future in which women would have more non-domestic freedoms, at least women over 40. At the same time, however, he predicts a future in which women have fewer sexual freedoms, at least compared to the century he knew best, the 12th.

White’s predictions for 2001:

I expect earlier marriages. Among the poor, marriage has very often been delayed until the male is prepared to support a family. Now our affluence is such that almost everybody can get married at a younger age. This trend will continue. Then, too, there is the psychological pressure rather unique to our times. It’s the growing conviction that restraint of sexual activity is positively dangerous, and therefore the sooner you can marry the children off, the better—this is mental health in a big way. What is tragic is the difficulty the people who wish to remain bachelors or spinsters experience in this society.
Second, I expect more family planning. Less in the sense of reducing the number of children than in enabling parents to ‘bunch’ their children. I believe that, in conjunction with early marriage, this bunching is very important and rather new. There will be an increasing number of women who have married early, who have bunched the children, and who, arriving at about their forties, find themselves relieved of detailed family responsibilities except for a vestigial husband. These essentially good developments will produce a rather profound malaise among people over forty, especially among women, in view of their increase in life expectancy.
The explosion of knowledge in our time and the new sophistication required for many professions have conspired with other factors to keep women, especially those over forty, immobilized in the home. Yet in a society where prestige goes to activists, it is terribly hard for intelligent women, after the brood is reared, to spend their talents simply on unsalaried good works and the care and feeding of husbands, who usually have their own occupational interests, quite apart from the lives of the wives. And this situation is not good for the husband, either. The dangerous age is no longer youth, I think. It is the year from forty onward.
Will there be more ‘sexual freedom’ in the future? I don’t think so. There has been in certain periods in the past remarkable sexual freedom in Western culture—simply amazing. And sexual freedom not only for men but for women as well, especially married women of the upper classes. These people got their sense of identity from the social class to which they belonged. Frequently they married not for love, but because marriage was an institution; they were pooling estates, they wanted heirs. In the late twelfth century, one finds ladies discussing whether it was moral for a wife to be in love with her husband. The general judgement was that no, it was not. One should not get love mixed up with as important a matter as marriage. Love is transient. It’s the bubbles in the wine. Marriage is serious. Now, in our vast—not quite ‘single class,’ but relatively homogenized—society, monogamy is a new way of discovering identity. Promiscuity is a way of losing it, as it was not in the past.

It is fascinating to wonder how McCall’s learned of White, who was apparently among “the world’s leading thinkers,” and why the editors thought a medievalist would have anything to say about the future.

Another Flat Earth Report

I can be persuaded to forgive President Obama when he invoked a mythcal past filled with people who believed in a flat earth. He is, after all, not trained in history or science or history of science. And he doesn’t pretend to have any expertise in history of science. It is more difficult to forgive for invoking the same myth. purports to be “the world’s No. 1 source for news of astronomy, skywatching, space exploration, commercial spaceflight and related technologies” and to have a “team of experienced reporters.” Such aspirations and the standards they imply should prevent from publishing any reference to a flat-earth past. Alas, those implicit standards seem to have had no effect on the historical accuracy of a recent article. In what can best be described as selective genealogy, Nola Taylor Redd claims that in the third century BCE “[w]hen most people believed the world was flat,” Eratosthenes measured its circumference:

When most people believed the world was flat, the notable Greek mathematician, astronomer and geographer Eratosthenes (276 BCE- 195 BCE) used the sun to measure the size of the round Earth. His measurement of 24,660 miles (39,690 kilometers) was only 211 miles (340 km) off the true measurement.

A recent article at repeats the Flat Earth myth.

This paragraph is alternately wrong and misleading. It is wrong to claim that during Eratosthenes life “most people believed the world was flat.” While it’s hard to know what “most people believed,” certainly most people whom we might call astronomers understood the earth was spherical. They could and did put forward compelling arguments for the earth’s sphericity, often grounding those arguments in philosophical assumptions or empirical observations or both. A century or so earlier Aristotle had already reported that certain mathematicians had calculated the size of the earth. When Eratosthenes devised a way to calculate the earth’s circumference, he was not unusual in his convictions. He calculated that the earth’s circumference was 252,000 stades, a number he probably rounded up from 250,000 so that it was divisible by 60. How long a stades was remains an open question. Most likely, Eratosthenes’ value would convert to something between 24,663 and 27,967 miles.

It is regrettable when a source like propagates myths like this. Even in a genealogical article, there is little reason to traffic in obvious historical myths.

[Reposted at PACHS.]

Toward a history of “eppur si muove”

Here I want to offer something of a history of Galileo’s unverifiable “eppur si muove.” My last post was not particularly helpful because it did not elevate the level of the discussion. I hope this post will contribute to a conversation about history and its uses. There is more at issue here than me just being an “overly literal type.” I worry that too many of readers won’t recognize why the sentiment and the quotation were ascribed to Galileo or the work the quotation does in our story of science and it’s relationship to non-science (society, politics, religion, etc.).

There is a the painting attributed to B. E. Murillo or somebody in his school in Madrid that represents Galileo in prison. When cleaned, in 1911, it turned out that the painting was larger than originally framed. When unfolded, it revealed that the figure of Galileo was gesturing toward the words “eppur si muove.” The painting seems to have been commissioned by Genreal Ottavio Piccolomini in Madrid, sometime between 1643 and 1650. John Heilbron, in his recent biography of Galileo, Galileo (OUP, 2010), associates the statement with Archbishop Ascanio Piccolomini, who had supported Galileo and his work, and with whom Galileo spent some months after his trial. Archbishop Piccolomini had few friends in the Vatican and continued to annoy the Church hierarchy by reportedly providing a safe place for Galileo to discuss his opinions. The Church grew tired of the archbishop’s sympathy for Galileo and ordered him removed from the archbishop’s residence in Siena (see Heilbron pp. 325–327).

There is, then, some evidence that the thought “And yet it moves” was ascribed to Galileo in the mid-seventeenth century, at least in Madrid perhaps by one of the Piccolomini brothers who was unhappy with the Church. But that does not constitute evidence that Galileo said those words. The standard account attributing this expression to Galileo derives from Stillman Drake’s Galileo at Work (Chicago, 1978), 356–357. There, Drake tells us that

[n]othing would have been more in character for Galileo, at the moment of leaving the hospitality of his good friend and host Ascanio Piccolomini, than—just before entering the waiting carriage—to stamp a foot on the ground, perhaps wink, and utter the famous words (357).

I confess that I would prefer stronger evidence for Galileo having said “eppur si muove” than Drake’s colorful recreation of the scene and his qualified assurance that “[q]uite possibly the story, which could not be circulated widely with safety to Galileo, was passed on within the [Piccolomini] family” and “[t]hereafter it lived on in oral tradition” before being “[p]rinted a century later” (357).

I have no doubt that Galileo continued to believe that the earth orbited the sun—his subsequent work bears witness to his conviction. But ascribing a sentiment to a person is different from attributing a quotation to that person. The painting, pace Drake, does not warrant putting the words into Galileo’s mouth. Nor does Giuseppe Baretti’s account from 1757, which “remains apparently the first statement of the myth” (M. Finocchiaro, Retrying Galileo (Berkeley, 2005), 114). Baretti, like Ottavio Piccolomini, was living in a foreign country where he could safely express his own displeasure with the Church.

It is not accidental that scientists and other non-historians repeat the story as if it is true. Perhaps the most famous is Stephen Hawking, who simply asserts in his recent book On the Shoulders of Giants: “Some historians believe that it was upon his transfer that Galileo actually said ‘Eppur si muove,’ rather than at his public abjuration following the trial” (p. 397). People too readily assume that because Hawking is a famous scientist he speaks the truth. Such an assumption, however, depends on an argument from authority. In this particular case, however smart and accomplished Hawking is, he is not a historian. His expertise in cosmology and theoretical physics does not confer expertise in history. Expertise is not fungible. Hawking lacks historical expertise and, consequently, authority in historical matters (for more on historical expertise, see here, here, here, here and here). Indeed, his On the Shoulders of Giants is not a work of history but rather, as the title suggests, a genealogy of science. Like all genealogies, it tells a triumphalist and therefore selective story about how the present came to be. Hawking has populated his book with the past scientists who, to his mind, have contributed to his science (for some of the problems with that, see my earlier post or either of Thony’s posts). Notably, Hawking included Galileo’s Dialogues Concerning Two New Sciences but nothing from Galileo’s astrology or his work on tides. This other material was probably excluded because either it is no longer science, as in the case of astrology, or Galileo got it wrong, as in the case of tides.

I would like to think that all reasonable readers recognize the Galileo story as probably apocryphal. However, as Hawking’s quotation above indicates, reasonable readers don’t consider “eppur si muove” as apocryphal—Hawking’s own formulation implies that the question is not if Galileo said “eppur si muove” but when Galileo said it. I think many reasonable people understand the story as having considerable truth in it. Examples of it being repeated by reasonable and educated people are easy to find. For example, even on such a science oriented blog as the Panda’s Thumb a commenter can invoke the Galileo myth apparently with full confidence that it is true; the Galileo Press, “a leading international publisher for computer and SAP books,” celebrates this story as a fact: “ Eppur si muove, (and yet it moves), he [Galileo] famously said after being forced to recant his heretical theory that the earth moves around the sun.” My concern seems to be shared by at least one other historian of science. In his recent biography of Galileo, Heilbron clearly thinks that most reasonable readers still need to be told that Galileo did not, in fact, say “still it moves:” “Galileo rose without muttering eppur si muove (“still it moves”) and returned, shattered, to the Medici palace” (p. 317).

We might argue about how much truth and how many readers and what constitutes reasonable, but given the problematic nature of the story, I think it calls for some qualification, some acknowledgement of or indication that the story is a myth or apocryphal or at least subject to debate. An explicit invocation of a literary adaptation of Galileo’s trial would also prevent confusion. Alluding to Andrea Sarti’s pleasant little tune, for example, would make clear that the reference should not be taken as historical fact but as fiction that aptly captured some sentiment:

The Bible proves the earth stands still,
The Pope, he swears with tears:
The earth stands still. To prove it so
He takes it by the ears.
And gentlefolk, they say so too.
Each learned doctor proves
(If you grease his palm): The earth stands still.
And yet—and yet it moves.
(B. Brecht, Galileo, Scene 8.)

Why does all this animate me so? At one level, I see in this yet another denial of historical expertise. Attributing to Galileo a statement for which there is no evidence suggests that what might or might not have happened and what might or might not be demonstrable according to the standards that govern the practice of history is irrelevant. Closely related to this concern is another about evidence. The problem in North Carolina seems to be that the legislature was considering passing a law that ignored relevant evidence, limited who could present evidence, and stipulated how evidence could be treated. If we are criticizing somebody for playing fast and loose with the evidence, it seems we have an obligation to be particularly careful what information we elevate to the level of evidence and how we use that evidence. At another level, along with their other functions myths serve to validate and reassert existing social orders and limit enquiry by making those social orders seem right, natural, and inevitable. If we are intellectually honest, in denying to Christians the validity of their creation myths because we see no evidence supporting those myths and can point to evidence that seems to deny them, shouldn’t we also deny validity to scientific myths when they lack supporting evidence and when we can point to evidence that seems to deny them? The deployment of questionable, apocryphal, or mythical information is never neutral or incidental. It always serves certain knowledge making and propaganda efforts.
[Reposted at PACHS.]