of the schools there in 1121. He went ca. 1124 to teach in Paris, where John of Salisbury
was one of his pupils. He continued in a conventional ecclesiastical career, becoming
archdeacon of Dreux in 1136 and archdeacon and chancellor of Chartres in 1141. In
1148, he was a member of the synod of Reims that condemned Gilbert of Poitiers and in
1149 was present at the Diet of Frankfurt. Sometime between 1151 and 1156, however,
he retired into a monastery, and we know nothing more of his life.
Thierry lays claim to be the most interesting Neoplatonist of Chartres. His
interpretation of Genesis 1, a commentary on Plato’s Timaeus called De sex dierum
operibus, contains his statement of divine formalism: that God is the form of all created
things. Thierry also displays the influence of Aristotelian logic. In the De sex dierum and
in his three commentaries on Boethius’s De Trinitate, he attempted to develop a rational
justification for the Trinity, describing it in terms of Aristotle’s four causes: Father as
efficient cause, Son as formal cause, Holy Spirit as final cause, and divinely created
matter as material cause. His other works include a commentary on Cicero’s De
inventione and a textbook for the Trivium and Quadrivium, the Heptateuchon.
Lesley J.Smith
[See also: CHARTRES; PHILOSOPHY; PLATO, INFLUENCE OF]
Thierry of Chartres. Commentaries on Boethius by Thierry of Chartres and His School, ed.
Nikolaus M.Häring. Toronto: Pontifical Institute of Mediaeval Studies, 1971.
——. The Latin Rhetorical Commentaries by Thierry of Chartres, ed. Karin M.Fredborg. Toronto:
Pontifical Institute of Mediaeval Studies, 1988.
Dronke, Peter, ed. A History of Twelfth-Century Western Philosophy. Cambridge: Cambridge
University Press, 1988, pp. 358–85.
THIRTY, COMBAT OF THE
. In 1351, the English garrison at Ploermel in Brittany was attacked by a French force
under Jean de Beaumanoir. To forestall a siege, Richard Bamborough, the garrison
commander, suggested a tournament-style combat on the open field in front of the castle
of Ploermel between thirty men-at-arms from each side. The fight was to be to the death.
Bamborough’s knights, who included Breton and German mercenaries as well as English
soldiers, were determined to fight so well that the legacy of such a chivalric battle would
be mentioned often among nobles. All fought on foot with swords, daggers, axes, and war
hammers. The battle was long and exhausting. A recess was taken, but battle soon
recommenced. In the end, after a diligent fight by the English, they were defeated when
one of the French knights unchivalrously mounted his horse and rode into them. Nine
English were killed, including Bamborough, and the rest were taken prisoner; six French
knights were slain.
Kelly De Vries
Froissart, Jean. Chroniques, ed. Siméon Luce et al. 15 vols. Paris: Renouard, 1869–1975, Vol. 4,
pp. 110–15.
Jean Le Bel. Chronique, ed. Jules Viard and Eugène Déprez. 2 vols. Paris: Renouard, 1904–05,
Vol. 2, pp. 194–97.
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