ORDERIC VITALIS
(d. ca. 1142). A monk of mixed Anglo-Norman parentage, Orderic Vitalis joined the
monastery of Saint-Évroult, in Normandy, ca. 1085. The other monks found his Saxon
name, Orderic, barbaric and renamed him Vitalis. His fame is due to his Historia
ecclesiastica. This work covers the history of Normandy, England, and northern France
from the late 11th century to 1141 and is one of the best sources of information on
Anglo-Norman society.
Constance B.Bouchard
Orderic Vitalis. Historia ecclesiastica, ed. and trans. Marjorie Chibnall. 6 vols. Oxford: Clarendon,
1969–80.
Chibnall, Marjorie. The World of Orderic Vitalis. Oxford: Clarendon, 1984.
ORESME, NICOLE
(ca. 1320/25–1382). A writer known mainly for his mathematical, scientific, and
economic treatises and for his vernacular translations of Aristotle. Educated in arts and
theology at the Collège de Navarre in Paris, Oresme was in 1356 appointed its grand
master. During this period, his long association with the royal family began; he may have
been tutor of John II’s son, the future Charles V.Partly because of his royal connections,
Oresme obtained church offices, becoming canon at Rouen (1362), canon at the Sainte-
Chapelle (1363), dean of the cathedral of Rouen (1364), and bishop of Lisieux (1377).
Oresme’s writings demonstrate his wide learning. His mathematical and scientific
works, such as De proportionibus proportionum, De configurationibus qualitatum et
motuum, and De commensurabilitate vel incommensurabilitate motuum celi, are
important for their treatment of fractional exponents, their graphic representation of
mathematical functions, and their sophisticated discussions of mechanics and astronomy.
Oresme also used his learning, in such treatises as Contra judiciarios astronomos, Livre
de divinacions, and De causis mirabilium, to attack the “misuse” of science, especially by
the astrologers.
Certain of Oresme’s works were written explicitly for the royal family. His economic
treatise, De mutationibus monetarum, was composed during the 1350s for John II. In the
late 1360s, Charles V asked Oresme to translate the Latin versions of four Aristotelian
texts, the Ethics, the Politics, the pseudo-Aristotelian Economics, and De caelo et mundo.
Oresme’s vernacular translations helped to create a flexible French prose and to expand
the French vocabulary, introducing as many as 1,000 new words.
Oresme has often been seen as anticipating modernity: in certain ways, his astronomy
foreshadows Copernicus, Galileo, and Kepler, and his mathematics Descartes; his
economics may anticipate Gresham’s Law. But Oresme is perhaps most impressive in his
ability to summarize and synthesize logically and intelligently, all the while advancing
the important theories of his age.
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