'''William of Auberive''' ({{langx|fr|Guillaume d'Auberive}}) was a Cistercian monk and numerologist who served as the abbot of {{ill|Abbey of Auberive|lt=Auberive|fr|Abbaye d'Auberive}} from 1165 until 1186.<ref name=URB>Uta-Renate Blumenthal, "Cardinal Albinus of Albano and the ''Digesta pauperis scolaris Albini'': Ms. Ottob. lat. 3057", ''Archivum Historiae Pontificiae'' '''20''' (1982): 7–49 (at p. 37, n. 124).</ref>
Two of William's treatises—''De sacramentis numerorum a ternario usque ad duodenarium'' and ''Regule arithmetice''—and three of his letters have been published.<ref>Robert Earl Kaske, Arthur Groos and Michael W. Twomey, ''Medieval Christian Literary Imagery: A Guide to Interpretation'' (University of Toronto Press, 1988), p. 171.</ref> He belonged to a group of Cistercians whose work was an expansion on the work of Hugh of Saint-Victor allegorizing numbers in the Bible. His ''De sacramentis'' on the numbers three (3) through twelve (12) is a direct continuation of the ''Analytica numerorum'' of Odo of Morimond on the first three natural numbers. It was itself followed by the work of Geoffrey of Auxerre, beginning with thirteen (13).<ref name=GB>Guy Beaujouan, "The Transformation of the Quadrivium", in Robert L. Benson, Giles Constable and Carol Dana Lanham (eds.), ''Renaissance and Renewal in the Twelfth Century'' (University of Toronto Press, 1991), pp. 463–487 (at 483).</ref> He was an influence on Theobald of Langres.<ref name=URB/><ref name=GB/>
William probably wrote around 1164, before he became abbot. He knew the ''De arithmetica'' of Boethius and was especially interested in perfect numbers. He invented some terms of his own. If the aliquot sum of a number was greater than the number, the difference between them he called ''fructus'' (fruit). If two numbers had identical aliquot sums, the sum was said be the "number of love".<ref name=GB/>
==Editions== *Leclercq, Jean. "L'arithmétique de Guillaume d'Auberive". ''Analecta Monastica'', 1st ser. Studia Anselmiana, 20. Vatican City, 1948. pp. 181–204. ''De sacramentis'' and the letter ''De sacramento quadragenarii'' are at pp. 197–202. *Lange, Hanne. "Les données mathématiques des traités du XII<sup>e</sup> siècle sur la symbolique des nombres". ''Cahiers de l'Institut du Moyen-Âge Grec et Latin'', '''32''' (1979):1–128. ''Regule arithmetice'' and two other letters are at pp. 86–117.
==References== {{reflist}}
Category:12th-century writers in Latin Category:Cistercian abbots Category:Numerologists Category:12th-century Christian abbots