GIOVANNI di MONTESONOS. - Dominican theologian, born in Monzón (Aragon) around the mid-14th century, died after 1412. In Barcelona in 1372 he lectured on the *Sentences*; in 1383 he taught theology in Valencia; in 1387 he was promoted to master at Paris. In his inaugural lecture as master, he advanced erroneous philosophical and theological propositions, including the heretical claim that it was heretical to uphold the Immaculate Conception of the Virgin, basing his assertion on the doctrine of St. Thomas Aquinas. The entire University of Paris was in uproar. A commission of masters examined his doctrine and condemned 14 propositions. The Archbishop of Paris imposed excommunication on anyone who upheld them (23 August 1387).
The part of the Dominican Order subject to Avignon, mistakenly believing that St. Thomas had been condemned, sided with him and appealed to the antipope Clement VII (1388). When the case began, G., fearing condemnation, fled to Aragon (January 1389), switching allegiance to Urban VI. He then went to Sicily. On 17 July 1393 he was appointed apostolic collector by the Bishop of Catania. Returning to his homeland, he was still alive in 1412.
Besides a *Tractatus de Conceptione B. Virginis*, he wrote in defense of Urban VI and Boniface IX: *Tractatus brevis de electione papae... qui dicitur informatorium* (1389, Paris, Bibliothèque nationale, cod. lat. 1466, ff. 611-707); *Correctorium contra epistolam fundamenti schismatis*; *Dialogus ad card. B.* (Bartolomeo Mezzavacca) *super schismate Ecclesiae* (Paris, ibid., ff. 1-610); *Opus quod dicitur Scopos 72 conclusionum ad peragrandam vitam Ecclesiae a devio triviali ad papam Bonifacium IX.*