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Guido de Baysio


Canonist; b. Reggio d'Emilia; d. Avignon, 1313. He studied in Bologna under the canonist Johannes de Anguissola and the professor of civil law Guido de Suzaria. Guido de Baysio first held ecclesiastical offices in Reggio, and in 1295 he received from Boniface VIII a canonicate and precentorship in Chartres. In 1296 he was made archdeacon of Bologna, from which office he is usually styled archidiaconus. He taught Canon Law in Bologna and was installed as professor of the Decretum of Gratian in 1301. Among his pupils were Alvarus Pelagius, Mattheus Romanus, and notably, Johannes Andreae. He is mentioned as auditor litterarum contradictarum in 1303.

His principal work was the Apparatus ad Decretum, called Rosarium, completed on Jan. 25, 1300. It is a Canon Law classic and is indispensable for a knowledge of older canonical writings. Guido de Baysio's chief ail in this work was to append material from the decretists and earlier decretalists not used in the glossa ordinaria on the Decretum of Gratian, as well as supplementary material written after the glossa ordinaria. His sources for pre-Johannine material on the Decretum are huguccio and the Glossa Palatina, which he ascribes in toto to Laurentius Hispanus. He also cites, from among the decretists, Bazianus, Bernardus Compostellanus Antiquus, Johannes Faventius, Melendus, P (Petrus Hispanus), and from among the post-Johannine decretists, he cites Bertrandus and Johannes de Phintona.

His Apparatus ad Sextum, written between 1306 and 1311, was the third classical commentary on the Liber Sextus, after the apparatuses of Johannes Monachus and Johannes Andreae. Following his usual pattern, he made use of the thought of older canonists, especially the early decretalists; the regulae iuris are not commented upon. The Tractatus super haeresi et aliis criminibus in causa templariorum et D. Bonifacii D.P. papae VIII, written at the time of the Council of Vienne, deals with the question of the Templars and is a defense of Boniface VIII. His Quaestiones, written in Reggio between 1283 and 1289, has never been printed.

Bibliography: j. f. von schulte, Die Geschichte der Quellen und der Literatur des Kanonischen Rechts, 3 v. in 4 (Stuttgart 187580) 2:186190. f. gillmann, "Die Abfassungszeit der Dekretsumme Huguccios," Archiv für katholisches Kirchenrecht 94 (1914) 246, note; "Guido de Baysio und Johannes de Anguissola," ibid. 104 (1924) 5455; "Johannes von Phintona, ein vergessener Kanonist des 13. Jahrhunderts," ibid. 116 (1936) 446484. s. kuttner, Repertorium der Kanonistik (Rome 1937); Studi e Testi 71 (Rome), 8788. s. kuttner, "Bernardus Compostellanus Antiquus," Traditio 1 (1943) 309. a. van hove, Commentarium Lovaniense in Codicem iuris canonici 1, v.15 (Mechlin 1928); v.1, Prolegomena (2d. ed. 1945), 1:455, 460. g. mollat, Dictionnaire de droit canonique, ed. r. naz, 7 v. (Paris 193565), 5:100708. a. m. stickler, "Decretisti Bolognesi dimenticati," Studia Gratiana 3 (1955) 386388. f. liotta, "Appunti per una biografia del canonista Guido da Baisio, arcidiacono de Bologna," Studi Senesi 76 (1964) 752. s. kuttner, introd. to repr. of Venice 1581 ed. of j. kuttner, In quinque decratalium libros: Novella commentaria, 5 v. in 4 (Turin 1963) 1:xixii, also in Jurist 24 (1964) 405.

[k. w. norr]

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