De ratione conputandi

Incoming data

The catalogue entry for this text has not been published as yet. Until then, a selection of data is made available below.

Manuscript witnesses

Brussels, Bibliothèque Royale de Belgique, MS 5413-5422/ff. 63-108, 117-124 
incipit: Sciendum nobis quomodo sol in principalibus linguis uocatur   No heading.
f. 77v.m–f. 107v
Vatican City, Biblioteca Apostolica Vaticana, MS Reg. lat. 1260 
ff. 87v–99v  


Primary sources Text editions and/or modern translations – in whole or in part – along with publications containing additions and corrections, if known. Diplomatic editions, facsimiles and digital image reproductions of the manuscripts are not always listed here but may be found in entries for the relevant manuscripts. For historical purposes, early editions, transcriptions and translations are not excluded, even if their reliability does not meet modern standards.

[ed.] Walsh, Maura, and Dáibhí Ó Cróinín, Cummian’s letter De controversia Paschali: together with a related Irish computistical tract De ratione conputandi, Studies and Texts 86, Toronto: Pontifical Institute of Mediaeval Studies, 1988.
CELT – De controversia Paschali, text (pp. 56–96): <link> CELT – De controversia Paschali, translation (pp. 57–95): <link>

Secondary sources (select)

Warntjes, Immo, The Munich computus: text and translation. Irish computistics between Isidore of Seville and the Venerable Bede and its reception in Carolingian times, Stuttgart, 2010.
Ó Cróinín, Dáibhí, “A seventh-century Irish computus from the circle of Cummianus”, Proceedings of the Royal Irish Academy 82 C (1982): 405–430.  
The Letter of Cummian on the Paschal question (c. A.D. 632) has long been recognised as one of the primary historical documents of the early Irish churches. The purpose of this paper is to show that a computus in Brussels, Bibliothèque royale, MS 5413-22, is the work either of Cummian himself or of a member of his immediate circle, and therefore represents an important new witness to the state of scientific learning in seventh-century Ireland.