Thursday, September 23, 2010

Why Should Anybody Care about Byzantine Science?

Posted by Darin Hayton on 09/23 at 10:48 PM

The Byzantine Studies Annual Conference takes place on 7-10 October here in Philadelphia. Tellingly, there are no papers at the conference that deal with Byzantine science (see the provisional program). On the one hand, the absence of papers seems to confirm the implicit judgement by David Lindberg, whose textbook, The Beginnings of Western Science. The European Scientific Tradition in Philosophical, Religious, and Institutional Context, 600 B.C. to A.D. 1450, contains only a brief mention of Byzantine science at the end of the chapter on the decline of science in the West.1 On the other hand, the lack of Byzantine science echoes the dismissive assessment of even Byzantinists themselves: Cyril Mango, certainly one of the foremost Byzantinists, recently pointed out that traditionally “Byzantium is not credited with any advance in science ….” As an example of the lack of scientific achievement, he offers:

Science, if that is the right word, was repesented by the Christian Topography of Kosmas Indikopleustes (sixth century), who demonstrated on the basis of the Bible that the world was shaped like a rectangular box.2

Fifty years ago Milton Anastos posed this as a puzzle: “The meager accomplishment of the Byzantines in the natural sciences remains one of the mysteries of the Greek Middle Ages.”3

Folio 230r from Barocci 166—the first folio of Nicephoros Gregoras’s text on the astrolabe (Source: Bodleian Library, University of Oxford)

Given the dismissal by both Byzantinists and historians of science, why should anybody bother with Byzantine science? To be fair, there are a handful of very skilled Byzantinists who have looked at Byzantine science, most notably Byzantine astronomy. Byzantine occult sciences too have attracted some attention. But in neither case do the scholars make much of an effort to explain why people beyond Byzantinists should bother.4 Perhaps by looking at one example of a Byzantine scientific text, we can begin to justify an interest in Byzantine science. The case study will be Nicephoros Gregoras’s text on the astrolabe. Gregoras (†1360) is known chiefly for his Roman History, but he also wrote on a variety of astronomical topics, including calendar reform, predictions of solar eclipses, date of Easter, as well as his treatise on the astrolabe.

Folio 316r from Vat. gr. 1087—an illustration from an early copy of Nicephoros Gregoras’s text on the astrolabe (Source: Bibliotheca Apostolica Vaticana, Vatican)

The Case for Studying Gregoras’s Text

In 1675 Edward Sherburne published his English translation of Manilius’s Astronomicon. While showing an interest in astronomy, Sherburne had no real expertise, as the notes to his translation reveal. To his translation he appended a list of important astronomers from antiquity to the seventeenth century.

I have therefore chosen for the better Information (and it may be Delectation) of the more Inquisitive and Ingenious Lovers of these studies, to collect a Catalogue of the most Eminent Astronomers, as well Ancient as Modern, their Works and Writings, according to the Succession of Time from the first Birth of Astronomy to this present, whereby the Curious Reader may perceive, when, how, and by whom it hat been improved to that Degree of Perfection wherein it now stands.5

Sherburne’s laundry list of astronomers provided for the late seventeenth century an astronomical canon. He included religious figures such as Adam and Zoroaster alongside mythical astronomers Atlas and Hermes as well as historical figures such as Anaxagoras and Eudoxus, and even a few Roman emperors (e.g., Julius Ceasar who “left several not unlearned books of the motions of the Stars,” Tiberius and Hadrian). Arranged chronologically, Sherburne mined classical sources such as Strabo and Pliny for references to any astronomical work. Of interest here is his entry for the year 1360, where Sherburne notes the contribution of Nicephoros Gregoras:

Nicephorus Gregoras, writ De astrolabio, extant in the King’s Library at St. Jame’s. Gesner mentions another Piece of his, De Calumniatoribus Astronomiae & De Astronomia. Andreas Cellarius, in Praeloquio Harmon. Macrocosm. reports that in the 27th year of his Age he applied himslef to Andronicus Palaeologus, Emperor of Constantinople, offering to him Reasons for the Emendation of the Roman Calendar.6

Sherburne did not construct his canon de novo. Instead, he compiled it from the many bibliographies in circulation at the time. The bulk of his sources came from recent bibliographies. Sherburne claimed to have exploited Conrand Gesner’s Bibliotheca universalis (1545), though his frequent references to Josias Simler’s edition of Gesner’s Epitome (1555) indicated that he found the synopsis more to his liking. He also relied on more specific bibliographic sources, such as Giovanni Baptista Riccioli’s catalog of astronomers that he added to his Almagestum novum (1651).

Despite Sherburne’s passing reference to an extant copy of Gregoras’s De astrolabio in the King’s Library at St. James’s, his use of existing bibliographies and biographical lists suggests that he did not, in fact, know Gregoras’s work except through other references to it. All of the recent sources that Sherburne cites include Gregoras in their lists of eminent authors. By 1545 Conrad Gesner has already identified Gregoras’s work as worthy of inclusion in his Bibliotheca universalis. Gesner, however, says nothing about Gregoras’s astronomical works. He lists, instead, Gregoras’s historical works, hist orations, and his commentary on Synesius. Gesner mentioned a commentary on Aristotle supposedly written by Gregoras, but then dismisses it as unlikely because he has not been able to find any such work: “But I have found nothing written on Aristotle by any author by this name, but by a Nicephorus Blemmida.”7 Gesner portrayed himself a careful scholar. Ten years later, when Josias Simler produced the Epitome of Gesner’s work, he added two general comments about Gregoras’s astronomical work: “De illis qui calumniantur astronomiam.” and “Ad eundem adhortatoria de astronomia.”8

When Sherburne turned his attention to more recent books on astronomy he found repeated references to Gregoras’s contributions to the development and spread of astronomy. In 1651 the Jesuit astronomer Giovanni Baptista Riccioli published his enormous defense of the Ptolemaic system, his Almagestum novum. He included in the first volume a list of the foremost astronomers from antiquity. Riccioli mentioned Gregoras’s astrolabe text, but provided no details or further justification for including the Byzantine astronomer. Ten years later, Andreas Cellarius again named Gregoras as one of the important astronomers of the past. Cellarius’s stated goal in offering his list was to provide a “glorification of the Republic of Letters, which was first bound within the borders of Greece, whence migrating to Italy, later, after the collapse of the Roman Empire, it was finally resurrected, and spreading throughout Europe, flourished in Germany, France, and Italy.”9 Appended to the front of his magisterial cosmography, the Harmonia cosmographica, Cellarius simply locates Gregoras in his prose narrative, claiming that when Gregoras was 27 he worked at Emperor Andronicus’s court in Constantinople. Implicitly, Cellarius identified Gregoras as a contributor to the development of astronomy, but he does not cite any work by the Byzantine astronomer.

By the middle of the seventeenth century, a generalized and ambiguous image of Gregoras the astronomer had come to occupy a space in the canon of astronomers, from Ptolemaic Jesuits in Rome, to Protestant cartographers in the Low Countries, to poet-dilettantes in England. A hint at how Gregoras came to occupy a place in the canon is provided by another reference in Sherburne’s list of authors who contributed to the progress of astronomy. Sherburne claimed that Italian humanist Giorgio Valla had translated various works from Greek into Latin and in 1536 had written a treatise on astrology, De tota astrologia, which included a book on the astrolabe, Fabrica ususque astrolabii exaratur.

Giorgio Valla died in 1500. He had spent most of his career teaching Latin and Greek in Pavia, Milan, and Venice, and translating numerous scientific works from Greek into Latin. Although classical Greek sources, especially Galen, occupied much of his time, Valla also produced a number of translations of Byzantine sources. In the area of medicine, he, along with other medical-humanists such as Alessandro Benedetti and Niccolò Leoniceno, were convinced of the superiority of Greek medicine over the contributions and, to their mind more common, errors of medieval medicine. This superiority was bound up with language. What hindered the medieval, especially Arabic, contributions were the errors in translation during the complex process of transmission from Greek, to Syriac and Arabic, and back into inelegant medieval Latin. Presumably, translating the original Greek into elegant, humanist Latin overcame these problems, restoring an accuracy to the texts they had lost.

In reality, however, Valla as often paraphrased a text as translated it. His Collectio. Georgio Valla Placentino Interprete was published in 1498 and provided paraphrases of two dozen Greek texts, and one Arabic. He was quite proud of this collection. About the same time it was published he wrote to a colleague, claiming that his book included many “neglected … and buried [material] from the most outstanding Greek writers.” One of the outstanding Greek writers was Nicephoros Gregoras.

Sometime in the late fifteenth century Valla had acquired a Greek codex that included an anonymous text on the astrolabe. Although Valla suspected that the text was by Gregoras, he was not certain. He wrote across the top of the first folio “On the astrolabe, I think by Gregoras or Philopponus, or maybe somebody else.”10 How Valla determined that his text was in fact by Gregoras remains a mystery, but by 1498 he had attributed the text to the Byzantine author and published his version as the fifth tract in his compendium, “Nicephorus de astrolabo.” Later, Valla almost certainly used his copy of Gregoras’s text when he composed his own Fabrica ususque astrolabii exaratur, which was published just after he died in his encyclopedic De expetendis et fugiendis rebus (Venice 1501), and was the text that Sherburne later cited. Valla’s De expetendis also included a translation of another Byzantine text on the astrolabe, this one by Johannes Philoponus.

Valla’s compendium and his encyclopedia found a wide readership, including Nicolaus Copernicus who quoted a number of classical sources from Valla’s translations.11 Within the tradition of texts on astrolabes and instruments, at least two early authors seem to have used Valla’s version of Gregoras’s “De astrolabo.”

Johannes Stöffler relied on Valla’s version of “De astrolabo” when he composed his own Elucidatio fabricae ususque astrolabii, which was first published in 1513 and went through more than a dozen editions. Stöffler’s text was divided into two parts—the first provided instructions for constructing an astrolabe and the second offered a number of canons on using the astrolabe. In the second part, on using the astrolabe, Stöffler mentions Gregoras’s method for finding the latitude of any region or city. Gregoras, he claimed, offered one particular method for finding the latitude of any location, namely when the sun entered Aries or Libra. Stöffler largely quoted Valla’s version of “De astrolabo,” and like Valla did not further describe Gregoras’s method. And while Stöffler admired Gregoras’s technique, he decided to offer his own, more general method because, as he said, the sun only enters Aries and Libra twice each year. Although Stöffler did not cite Gregoras at any other point in his textbook, the popularity of the Elucidatio could have introduced Gregoras and his text on the astrolabe to many people. Subsequent editions of Stöffler’s text continued to cite Gregoras. Another important book on instruments that refers to the same passage from Gregoras’s text is Peter Apian’s Instrument Buch, first published in 1533. It is unclear if Apian used Stöffler as his source for this citation, or if he used Valla’s translation. In either case, Apain’s text further disseminated Gregoras’s reputation. A fuller survey of astrolabe texts in sixteenth-century Europe promises to reveal further citations to Gregoras’s text.

Although Gregoras’s text contributed little to the content of 16th-century texts on constructing and using astrolabes, it became an important source of authority for European authors. Indeed, by the end of the century Gregoras had acquired such a reputation that he was inserted into the canon of astronomers, despite the fact that the only text commonly known in Europe was his short treatise on the astrolabe. Whether or not we want to see his text as having made some important contribution to the development of astrolabes, 16th- and 17th-century European scholars thought him important enough to cite repeatedly and to incorporate into their surveys of imminent astronomers. Perhaps then the reason to study Byzantine science is not for its advances in science, but because so many early-modern scholars, astronomers, physicians, mathematicians, etc. considered Byzantine science important.12

1The first edition of Lindberg’s text spent about a page and a half discussing Byzantine science in the context of its contribution to Islamic science. The new edition has moved that brief discussion into the chapter that traces the decline of science in the Roman Empire, but does not appreciably expand it (While doubling the length of the section certainly adds material, it seems a bit of a backhanded compliment when Byzantine science still only receives three pages and a few scattered mentions).
2C. Mango, “Byzantium’s Role in World History” in The Oxford Handbook of Byzantine Studies, ed. E. Jeffreys, J. Haldon, and R. Cormack (Oxford: OUP, 2008), 958, 959–60.
3M. Anastos, “The History of Byzantine Science,” Dumbarton Oaks Papers 16 (1962), 409–11, quotation at 411.
4See the incredible work by A. Tihon, including her recent survey of Byzantine science: A. Tihon, “Numeracy and Science” in The Oxford Handbook of Byzantine Studies, ed. E. Jeffreys, J. Haldon, and R. Cormack (Oxford: OUP, 2008). For the occult sciences, see P. Magdalino and M. Mavroudi, The Occult Sciences in Byzantium (Geneva: La Pomme d’Or, 2006).
5Edward Sherburne, The Sphere of Marcus Manilius made an English Poem: With Annotations and an Astronomical Appendix (London: Nathanael Brooke, 1675), 5.
6Ibid., 37.
7Conrad Gesner, Bibliotheca universalis (1545), 516v.
8Josias Simler, Epitome (1555), 134v–135r.
9Andreas Cellarius, Harmonia cosmographica (1661), 125.
10Nicephoros Gregoras, “Τοῦ Γρηγορᾶ κυροῦ Νικηφόρου τοῦ φιλοσόφου πόνημα περὶ κατασκευῆς καὶ γενέσεως ἀστρολάβου,” Modena, cod. 132, Valla’s quotation from fol. 16v.
11Edward Rosen, “Nicholas Copernicus and Giorgio Valla,” Physis (1981): 451–54.
12A similar story could be told about Michael Psellos’s text on demonology, which Marsilio Ficino first translated into Latin. Psellos’s text enjoyed a wide readership and exerted considerable authority into the late 17th-century. See, D. Hayton, “Michael Psellos’s De daemonibus in the Renaissance,” in Reading Michael Psellos, ed. Charles Barber and David Jenkins (Leiden: Brill, 2006), 205—27.

Tags: astrolabes, byzantine science, giorgio valla, nikephoros gregoras


Comment posted by Thony C. on 09/26 at 04:31 AM

While the first edition of Lindberg’s text spent about a page dismissing Byzantine science, the new editions has lost even that brief discussion.


The section on Byzantine science has been enlarged. Lindberg, “The Beginnings of Western Science”, 2nd. ed. 2007, Preface p xv

Learning and Science in the Greek East Lindberg, as above, pp 159 - 162.

Gregoras doesn’t get a name check!

Comment posted by Darin on 09/26 at 06:40 AM


Thanks for keeping me honest!

I’ve edited the post and the note to make the point I was trying (and failing) to make the first time around.

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