ROSCELLINUS (RUCELINUS, or ROUSSELIN) (c. loso-c. 1122), often called the founder of Nominalism (see SCHOLASTICISM), was born at Compiegne (Compendium). Little is known of his life, and our knowledge of his doctrines is mainly derived from Anselm, Abelard and John of Salisbury. He studied at Soissons and Reims, was afterwards attached to the cathedral of Chartres, and became canon of Compiegne. It seems most probable that Roscellinus was not strictly the first to promulgate nominalistic doctrines; but in his exposition they received more definite expression, and, being applied to the dogma of the Trinity, attracted universal attention. Roscellinus maintained that it is merely a habit of speech which prevents our speaking of the three persons as three substances or three Gods. If it were otherwise, and the three persons were really one substance or thing (una res), we should be forced to admit that the Father and the Holy Spirit became incarnate along with the Son. Roscellinus seems to have put forward this doctrine in perfect good faith, and to have claimed for it at first the authority of Lanfranc and Anselm. In 1092, however, a council convoked by the archbishop of Reims condemned his interpretation, and Roscellinus, who was in danger of being stoned to death by the orthodox populace, recanted his error. He fled to England, but having made himself unpopular by an attack on the doctrines of Anselm, he left the country and repaired to Rome, where he was well received and became reconciled to the Church. He then returned to France, taught at Tours and Loc-menach (Loches) in Brittany (where he had Abelard as a pupil), and finally became canon of Besanfon. He is heard of as late as 1121, when he came forward to oppose Abelard's views on the Trinity.
Of the writings of Roscellinus, nothing is preserved except a letter to Abelard, mainly concerned with the doctrine of the Trinity (ed. J. A. Schmellcr, Munich, 1850). See F. Picaret, Rosselin, philosophe et theologien (1896), and authorities quoted under SCHOLASTICISM.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)