ALFA kick-off conference

September 27-29, 2017

Observatoire de Paris


Organisation: Matthieu Husson, José Chabás, Richard Kremer and the ALFA team

This first conference will be devoted to a general presentation of the project’s purpose and approaches, to a critical reflection on its relations to neighbouring fields of scholarship and to the definition of the first steps of the collective work.

Access will be on 77 avenue Denfert Rochereau 75014 Paris.

The conference is open to the public but due to security reasons registration is mandatory. If you want to attend please send an email to before Septembre, Tuesday 25.


Conference program


September, Wenesday 27

Salle du Conseil, Batiment Perault


Welcome coffee


An introduction to the project ALFA

Matthieu Husson (CNRS, Observatoire de Paris)

Alfonsine astronomy is arguably among the first European scientific achievements. It shaped a scene for actors like Regiomontanus or Copernicus. There is however little detailed historical analysis encompassing its development in its full breadth. ALFA addresses this issue by studying tables, instruments, mathematical and theoretical texts in a methodologically innovative way relying on approaches from the history of manuscript cultures, history of mathematics, and history of astronomy. Relying on these approaches the main objectives of ALFA are thus to:

  • Retrace the development of the corpus of Alfonsine texts from its origin in the second half of the 13th century to the end of the 15th century by following, on the manuscript level, the milieus fostering it;
  • Analyse the Alfonsine astronomers’ practices, their relations to mathematics, to the natural world, to proofs and justification, their intellectual context and audiences;
  • Build meaningful narratives showing how astronomers in different milieus with diverse practices shaped, also from Arabic materials, an original scientific scene in Europe.

ALFA will shed new light on the intellectual history of the late medieval period as a whole and produce a better understanding of its relations to related scientific periods in Europe and beyond. It will also produce methodological breakthroughs impacting the ways history of knowledge is practiced outside the field of ancient and medieval sciences


The place of astronomical knowledge in Western medieval culture

Danielle Jacquart (EPHE, Paris)

As it was the case in other fields, but perhaps to a larger extent, the translations into Latin of Arabic astronomical works came up to Western expectations. It was due to the wide range of intellectual interests that astronomical knowledge could meet, from the exegesis of some biblical passages or the curiosity about the natural world to more practical concerns, such as the calendar or astrological applications. In this paper a survey of all these implications will be presented on the basis of few examples, following the evolution from the centuries before the translations from Arabic to the end of the Middle Ages. An attention will be paid also to the training and the diverse competences in this field, according to the motivations of those who illustrated it in some way or another.




What is at stake in bridging the history of mathematics and the history of the astral sciences? An approach from the perspective of mathematical practices

Karine Chemla (CNRS, SPHERE-Université Paris Diderot)

In the last decades, the history of mathematics and the history of the astral sciences have developed for the most part independently from one another. This is clear, for instance, if one observes how neatly the two fields are represented in congresses on the history of science. Except for mentions of major mathematical innovations that were devised in the context of the astral sciences, or in relation to them, like the so-called “Chinese remainder theorem,” on the average practitioners of the history of mathematics have not taken sources in the astral sciences into account, as if nothing of interest for the historian of mathematics could be found in them. Similarly, except for an interest in the application of mathematics to the astral sciences, practitioners of the history of the astral sciences have for the most part considered that the mathematical tools used or even shaped in the context of the astral sciences were transparent, and they focused rather on issues like the accuracy and circulation of parameters and the adequacy of models and observations.

In the context of the SAW project (2011-2017), we have attempted to establish bridges between these two fields, and we have come to share the conviction that such bridges could be beneficial to both fields. In this talk, I would like to evoke some of the lines of inquiry that we have shaped in this context and also some of the benefits that we have envisioned and even begun drawi,g from this interaction. I will argue in particular that to this end the “practice turn” in the history of science, in a sense to be made clear, offers an opportunity. My hope is that ALFA can offer a new context in which this effort can be carried on.


A few remarks on the Alfonsine Tables and its Arabic sources

Julio Samsó (Universitat de Barcelona, Barcelona)

Many astronomical works patronized by King Alfonso are based on Arabic sources and this is obvious in the case of the Libros del saber de astronomía. Establishing links between Arabic zījes and the Alfonsine Tables is not so easy, although I made an attempt along this line many years ago. Most of the documented sources are Andalusī, as they were easily available to the king’s astronomers. In this paper we survey such sources in relation to Ibn al-Zarqālluh’s innovations in astronomical theory, to Ibn Ishāq and the obliquity of the ecliptic, to the lunar correction and to the sexagesimal structure of calendar and mean motion tables. It would be interesting, however, to find evidence about their use of Eastern sources, as we know that Alfonso X maintained diplomatic relationships with Egypt: Castilian embassies were sent to Cairo, and we know of an Egyptian embassy, sent by the sultan Baybars, which arrived to Seville in 1261.




Where Mind and Matter Meet: Manucsripts as Artefacts

Michael Friedrich (Centre for the Study of Manuscript cultures, Hamburg)

Abstract to be announced


Conclusion of the day


September, Thursday 28

Salle du conseil, Batiment Perault


Alfonsine Astronomy in Italy: Current Situation and Perspectives

José Chabás (Universitat Pompeu Fabra, Barcelona)

The aim of this presentation is to provide the main elements of the current state in the study of Alfonsine astronomy and its diffusion in Italy in the14th and 15th centuries, and to suggest areas where more work is needed. It is also an invitation to all participants to contribute to this draft survey in order to build a more complete picture of the astronomical activity in Italy during this fruitful period.


Preparation of a List of Central European Mss. with Alphonsine Astronomy and Creation of Editions of Chosen Texts

Alena Hadravová, (Academy of Sciences of the Czech Republic)

In the framework of the ALFA-project I would like to deal with the following four topics:

  • List of the Alfonsine tables saved in Czech and Moravian libraries (especially Prague: National Library, Library of the National Muzeum, Library of the Metropolitan Chapter, Library of Strahov Monastery; Brno: Moravian Library; castle libraries etc.). The foundation of the University in Prague (1348), and later in Cracow (1364), Vienna (1365) or Erfurt (1392), was an important milestone for intensity of copying and reception of the tables and other astronomical texts. These universities were mutually connected by frequent peregrinatio academica of their students, which stimulated also the spreading of the literature. The list will thus be extended also on these other centers of learning in Central Europe. In addition to the mentioned university towns there were also important contacts between Bohemia and Northern Italy (cf. e.g. frequent copies of Giovanni Bianchini’s tables in Czech libraries). It is necessary to describe the tables and to classify them according their types.
  • Geographic tables of towns. One by-product of study of the tables can also be the collection of geographic coordinates of towns and regions. I was collecting it for many years from various treatises and it includes now about 50 tables. I would like to make it available as a database to those interested in their study.
  • Study of the textual parts of the tables. Simultaneously with the assembling the list of the tables and their classification I intend to study up to now unpublished rules (canons) for use of the tables. We can find such examples e.g. in tables calculated for the Prague meridian (mss. Prague, NL X B 3; NL VIII G 24 /without the rules/; Vienna, ÖNB 5245; Oxford, Bodl. Lib., Canon. Misc. 499; Cracow, BJ 610; BJ 553 etc.). A detailed study also deserves the ms. Toruń, BU 74 with Alfonsine tables with which we dealt recently. This ms. from 1425 was written in Bohemia and was in possession of Wenceslas Koranda.
  • Editions of related Medieval Latin texts. Being a classical philologist specialized in medieval Latin I see the best option for my contribution to the ALFA project in preparation of critical editions of some texts, i.e. in addition to the above mentioned rules some other chosen texts devoted, e.g., to a construction and use of some instruments. An example of such our previous work is the edition of treatises on astrolabe by Cristannus of Prachaticz; his work was published as the first incunabulum on this topic in Perugia c. 1478. We are open to collaborate on other treatises which will be of interest of the ALFA project.




Two Fifteenth-Century Alfonsine Astronomers and Their Milieu

Richard Kremer (Dartmouth College, USA)

One of ALFA’s central concepts is that of the “milieu”, viz., a geographical, sociological or chronological “space” in which a “specific set of intellectual practices” can be identified, in our case a specific approach to “Alfonsine astronomy”.  To explore how this concept might enrich the study of Alfonsine astronomy, I will compare two mid fifteenth-century individuals who copied or collected Alfonsine texts.  Although probably neither would have designated himself as an “astronomer,” nonetheless they both practiced Alfonsine astronomy but in quite different milieus.

Fridericus Amann in the 1420s studied at the university in Leipzig, became a monk and in the 1440s joined the Benedictine cloister St. Emmeram in Regensburg where he remained until his death c. 1465.  Best known for writing the first algebra in German and for contributing to the first printed Rechenbuch (Bamberg 1483), Amann also copied at least seven codices filled with Alfonsine, medical, astrological, calendrical and computistic material (Clm 14111, 14504, 14583, 16222, 14783 and 14908, Vat. pal. lat. 1376). In 1447, he wrote a lengthy canon to what he called the “Erfurt Tables” (probably a mixture of the Alfonsine tables and those of John of Lignères); in 1453, he described his own observation of a lunar eclipse; in 1458, he wrote a short canon to the Oxford Tables.  What can Amann’s manuscripts tell us about the milieu of St. Emmeram, one of the oldest monasteries north of the Alps (founded 739)?

A generation later, Hartmann Schedel (1440-1514), the well-known Nuremberg physician, humanist, book collector, and author of the spectacularly printed Weltchronik (1493), also copied astronomical, astrological and medical texts and collected astronomical instruments in paper and brass.  In the 1460s, Schedel studied medicine in Padua and began to learn Greek. His massive library contains three codices of Alfonsine materials (Clm 27, 83, 275).  Apart from some notes on comets, it is not known whether Schedel himself composed any astronomical texts.  But the types of tables and texts he collected can illustrate how he practiced astronomy as a wealthy Burger and politically influential physician in the milieu of Nuremberg, the leading commercial and trading center of fifteenth-century central Europe.




Questions Concerning Trigonometry in Medieval Europe

Glen van Brummelen (Quest university, Canada)

The development of trigonometry in Europe from the 13th to the 15th century is not adequately understood. In general the trajectory follows that of computational needs in astronomy; demands for tables of sines and of newly-invented “auxiliary functions” provided motivation for innovations. The theoretical side of the subject culminated eventually in Regiomontanus’s “De triangulis omnimodis”. Scholarly debate surrounding the work’s originality has focussed on the origins of many of its theorems in predecessors in Europe and Islam. However, what makes the work unique and a basis for later work is its comprehensiveness, and its emphasis on triangles as primitive objects. We find a predecessor of this approach in a passage (authored by someone else) in John of Murs’ “De arte mensurandi”. This and a couple of other works raise the possibility that trigonometry grew in the presence not just of astronomy, but also of practical geometry.




Jean de Lignères, astronome parisien du début du XIV siècle: quelle place dans la tradition alfonsine? Pistes de recherche pour le projet ALFA

Marie-Madeleine Saby (université de Grenoble Alpes, Grenoble)

Il s’agira de replacer les travaux de Jean de Lignères relevant de l’astronomie alfonsine, et en particulier les canons de 1322, dans le contexte de l’activité d’une véritable équipe scientifique. Trois savants, Jean de Murs, Jean de Lignères et Jean de Saxe, ont en effet travaillé dans une communauté de lieu, d’action et de temps quasi parfaite. Ils ont su développer une influence incontestable dans les milieux universitaires du temps et ont pleinement participé à la construction d’un nouveau concept d’astronomie, plus ou moins inspiré par Alfonse X de Castille. Les caractères proprement « alfonsins » dans leur production (textes et tables), et notamment dans l’œuvre de Jean de Lignères,  se sont constitués en quelques années. Ces travaux ont été diffusés dans tout l’occident jusqu’à la fin du moyen âge, en témoignent les nombreux manuscrits conservés et les caractères propres de la tradition de tels  textes scientifiques. Les canons de 1322  (44 sur le premier mobile, 46 sur le mouvement des planètes) participeront au programme d’édition d’ALFA avec d’autres textes de Jean de Lignères. A ces “textes d’usages”  il conviendra de faire correspondre les tables astronomiques, pour reconstituer cet Opus astronomicum, tel qu’il a sans doute été voulu à l’origine par Jean de Lignères.


September, Friday 29

Salle du Levant, Batiment Perault


General organisation concerns

Matthieu Husson(CNRS, SYRTE-Observatoire de Paris), Marine Pailler (CNRS, SYRTE-Observatoire de Paris)/Galla Topalian (CNRS, SYRTE-Observatoire de Paris)

In this short presentation We will precise organisational matters so that the general schedule of the project, the various tools we are going to use and build to work collectively and the administrative rules we are submitted to from the CNRS and the ERC are presented.


The Study and Critique of Alfonsine Astronomy in Fourteenth-Century Erfurt and Paris: Heinrich Selder’s Canones of 1365

Philipp E. Nothaft (All Souls College, Oxford)

My talk is based on a preliminary survey of the Canones on the Alfonsine Tables produced in 1365 by the Swabian astronomer Heinrich Selder, which are the most voluminous and sophisticated such text extant from the fourteenth century. Besides exploring the background and content of Selder’s Canones and their transmission in more than a dozen manuscripts, the presentation also aims to draw attention to the general importance of canons as a vehicle for the study, teaching, and dissemination of Alfonsine astronomy during the late Middle Ages. It invites participants to discuss the possible classification and typology of such texts and to sketch future avenues of research.




Selected topics from the medieval astronomy

Petr Hadrava (Academy of Sciences of the Czech Republic)

In the contribution a brief summary will be presented of topics from medieval astronomy which we have dealt with and which may be a starting point for further studies in the framework of the ALFA project. They include both astronomical tables (e.g. tables of lunar equations, trepidation etc.), or astronomical instruments and treatises on their construction and use. These instruments are, e.g. the astrolabe (described by Cristannus of Prachatice), eclipse instrument (by Johannes Sindel) or the Ptolemaic globe (saved in Bernkastel-Kues). Another subject currently in progress are the commentaries by Wenceslas Faber of Budweiss on Sacrobosco’s Sphaera.




Alfonsine Astronomy, building a perspective from the history of mathematics

Matthieu Husson (CNRS, Observatoire de Paris)

The corpus of Alfonsine texts, as defined broadly in ALFA includes different types of contents: tables, canons, instruments texts, theoretical texts, mathematical texts at least. This variety attest the diversity and complexity of intellectual practices produced in various contexts by historical actors when engaging with and fostering Alfonsine astronomy. Among the various perspectives one can adopt to explore and study this corpus I would like to continue the path I’ve chosen since the beginning of my research: look at the corpus with history of mathematics questions. Thus I will for instance seek actors’ arithmetical, geometrical, trigonometrical, reasoning practices. I will also analyse how these practices are articulated to their access, production and uses of manuscripts as well as to their astronomical practices. In this presentation I want to workshop with the team the different steps I could take in order to achieve this general aim by the end of the project and map also the possible collaboration among us would be pertinent in this context.




Final discussion