Catholic Encyclopedia (1913)/Theodoric of Chartres
Theodoric (Thierry) of Chartres, Platonist philosopher of the twelfth century, b. in France at the beginning of the twelfth century; d. at Chartres about 1150. It is probable that he studied at Chartres under his brother Bernard, at least, we know that in 1121 he was head of the school of Chartres. Later, he seems to have gone to Paris and to have taught there, among his disciples being John of Salisbury. In 1141 he was teaching once more at Chartres. He wrote a work on the seven liberal arts entitled "Eptateuchon", a treatise "De Sex Dierum Operibus", and a commentary on "De Inventione Rhetorica ad Herennium". The first still exists in MS. at Chartres, the others were published 1884 and 1890. Theodoric was an ardent lover of the Classics, the study of which he defended against the sect of Obscurantists known as "Cornificians". He was also interested in the natural sciences, as is indicated by the fact that he was the recipient of a Latin translation of the "Planisphere" of Ptolemy made by Herman the Dalmatian. In philosophy he adopted the Platonic explanation of reality and the ultra-realistic theory of universals. He was influenced also by neo-Pythagorean principles. Nevertheless, he did not, as was formerly contended, go the length of professing explicit pantheism; he did not identify Divinity with reality. He did, indeed, maintain that Divinity is a form of essence (forma essendi) in all things; but, as Baumker has shown (Archiv f. Gesch. der Phil., X, 138) we are to understand this phrase in a theistic sense. For, while it necessarily implies the existence of a Divine something in all things, it does not imply the identity of the essence of God with the individual essences of things. In his exposition of the first chapters of Genesis (De Sex Dierum Operibus) he attempts to reconcile the Mosaic account of creation with the Platonic explanation of the origin of the universe.
CLERVAL, Les ecoles de Chartres (Paris, 1895), 169 sqq.; DE WULF, Hist. of Medieval Phil., tr. COFFEY (New York, 1909), 182 sqq.; BAUMKER in Archiv. f. Gesch. der Phil., X; TURNER, Hist. of Philosophy (Boston, 1903), 294.