Immo Warntjes's picture
July 8, 2016 to July 10, 2016
Ireland {Republic}
Subject Fields: 
Intellectual History, Medieval and Byzantine History / Studies, History of Science, Medicine, and Technology

Since 2006, the Moore Institute of the National University of Ireland in Galway hosts, under the direction of Professor Dáibhí Ó Cróinín, a biannual conference on the science of computus in the Middle Ages. The science of computus – the mathematics required to calculate the date of Easter, and related topics (incl. astronomical observations and calculations) – straddles the fields of mathematics and astronomy, biblical interpretation and cosmology, empirical astronomical observation, and the perennial quest to understand the concepts of time and time-reckoning.

The core period covered by the conference stretches from the formation of Easter calculations in the third century to the introduction of Arabic and Greek science in the Latin West in the 12th century, but papers on the reckoning of time and its cultural context in the later Middle Ages have also always been welcomed. Each conference had a special theme (the formation of computus in Late Antiquity; the rise of prognostications in the early Middle Ages; the revolution of computus in the 11th and 12th centuries; etc.).

The establishment of the Galway conference in 2006 and the simultaneous publication of Arno Borst’s 3-volume Schriften zur Komputistik im Frankenreich, 721818 (which was launched in Galway that year) brought the subject into the mainstream of Medieval Studies. The progress since has been immense, and the 10th anniversary of both the Galway conference and Borst’s Schriften is the ideal time to review this progress. Therefore, the 6th International Conference on the Science of Computus in the Middle Ages, to be held in Galway on 8-10 July 2016, will have a major emphasis on scientific thought in the Carolingian period.


6th International Conference on the Science of Computus in the Middle Ages

Old Moore Institute, NUI Galway, 8-10 July 2016


Friday, 8 July

16:00-18:00 — Session 1: Liber Nemroth

Barbara Obrist (Geneva)  Nemroth’s cosmology and computus in the 12th century

David Juste (Munich)  The lost astrological chapters of the Liber Nemroth and the origin of the text

Philipp Nothaft (Oxford)  Chronology and computus in the Liber Nemroth

Isabelle Draelants (Paris)  Depingimus demonstrando: dialogue between drawings and text for learning efficiency in Nimrod’s cosmogony

18:15 — Book-Launch

20:30 — Conference dinner


Saturday, 9 July

9:00-10:00 — Session 2: The Calculation of Easter

Marina Smyth (Notre Dame) – Verse mnemonics similar to Nonae Aprilis

Michael Brennan (Dublin) – Mathematicians in the Carolingian age: Asking in an age of answers


10:30-12:30 — Session 3:  Bede & his Legacy

Conor O’Brien (Cambridge)  The scandal of diversity: The uses of tolerance in the early medieval Easter Controversy

Máirín MacCarron (Sheffield)  Why did Bede include a chronicle in his De temporibus?

Joshua Westgard (Michigan)  The transmission of Bede’s scientific works

John J. Contreni (Purdue)  A first look at ninth-century glosses on Bede’s De temporum ratione


14:30-16:00 — Session 4:  The Computi of 757 & 789

James Palmer (St Andrews)  The many lives of a ‘faulty’ prototype: the computus of 757 and its relatives

Leofranc Holford-Strevens (Oxford)  The Computus of 757: text and context

Immo Warntjes (Belfast)  The unfinished Fulda Computus of AD 789


16:30-18:00 — Session 5:  Manuscripts I

Dimitry Starostin (St Petersburg)  Alcuin, Hildebald, and MS. Cologne Dombibliothek 832: Computus and cultural conflicts in time-reckoning among the Carolingian educated elite

Eric Ramírez-Weaver (Princeton / Virginia)  Calculated differences: meaning and change in the image cycle of the Libri computi of AD 809

Brigitte Englisch (Paderborn)  Mundus pictus: Die bildliche Darstellung astronomischer und geographischer Strukturen in komputistischen Handschriften des 9. Jhs.


Sunday, 11 July

9:00-10:30 — Session 6:  Manuscripts II

Lisa Chen Obrist (Toronto)  Seeing the sources in Book X of Hrabanus Maurus’ De rerum naturis

Wesley Stevens (Manitoba)  Questions about the Tabula paschalis of Dionysius Exiguus from its earliest manuscript

Richard Corradini (Vienna)  Mastering time: the chronographic collection in Walahfrid Strabo’s handbook


11:00-12:00 — Session 7:  Arabic Influences

Fathi Jarray (Tunis)  Astronomie et Gnomonique musulmanes et l’Europe médiéval: rapports d’influence ou héritage partagé?

Michael Schonhardt (Freiburg)  … ut fratres surgere faciat ad horma competentem: the transmission and function of Arabic science in Regensburg


13:30-15:00 — Session 8:  Late Anglo-Saxon Computistics

Megan McNamee (Michigan)  Abbo’s numerical pedagogy

Sabine Rauch (Dublin)  Number symbolic ideas in Byrhtferth’s diagrams of the Enchiridion

Rebecca Stephenson (Dublin)  Visualizing computus: Byrhtferth of Ramsey’s diagrams


15:30-17:00 — Session 9:  Later Middle Ages

Sarah Griffin (Oxford)  Diagram and dimension: visualising time in a drawing of Opicinus de Canistris (1296 - c.1354)

Christian Etheridge (Odense)  The development of computus texts in Sweden and Finland in the Middle Ages

Michal Choptiany (Warsaw)  An understudied Cistercian computistical source from Silesia: Conrad of Heinrichau’s Computus novus ecclesiasticus (1340)


Contact Info: 
Immo Warntjes
School of History
Queen's University Belfast
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