Catholic Encyclopedia (1913)/John of Janduno
An Averroistic philosopher, theologian, and political writer of the fourteenth century. John of Janduno (Johannes de Genduno, de Ganduno, and de Gandavo) and John of Gand (or less correctly, of Ghent) are now generally said to have been two different persons. The former was born about the year 1300, graduated in arts at the College of Navarre (University of Paris), wrote a work entitled "De Laudibus Parisiis," and, in collaboration with Marsilius of Padua, composed the celebrated "Defensor pacis," directed against Pope John XXII, for which the authors were condemned in 1327. John of Gand was born about 1270 or 1280, studied theology at the Sorbonne, and after having served as curé at Kieldrecht was made a canon of the cathedral of Paris. These facts seem to be clearly established. However, there are extant a number of works, mostly philosophical, which are ascribed to Johannes de Genduno, Ganduno, or Gandavo, and it is difficult to say whether they were written by John of Janduno or by John of Gand.
These works include commentaries on Peter Lombard's "Books of Sentences," on Aristotle's "Physics," "Metaphysics," and "The Soul," also a treatise entitled "Quaestio in Averroem de substantia orbis." The author is strongly inclined towards the doctrines of Averroes. He defends the principle of twofold truth, according to which what is false in philosophy may be true in theology, or vice versa. Thus, he says, the eternity of the world is demonstrated in philosophy to be true and yet in theology it is false; according to this principle, we are to believe that the world was made, while we know that it was not made. Again, he holds the Averroistic doctrine that there is only one intellect, which is common to all men, and is in no sense a part of the individual soul. Consequently, he is obliged to maintain that the immortality of the individual soul cannot be proved in philosophy. In his discussion of the nature and operations of the human mind he takes sides with the determinists, who deny that the will is free. Finally, the Averroist author of these commentaries is no friend of the Thomistic school. He tries to belittle the reputation of St. Thomas, and to prove him inferior to Averroes. Considering, therefore, the spirit and tendency of these works, one is inclined to assign them to the turbulent, anti-papal author of the "Defensor pacis," and not to the theologian and canon who, for all we know, troubled himself as little about the intellectual warfare going on between Thomists and Averroists as he did about the political conflict between Pope John XXII and Louis of Bavaria. The commentaries mentioned above and the "Quaestio" were published in Venice, 1497, 1525, etc.
DE WULF, Histoire de la phil. mediev. (Louvain, 1902), 372 sqq,; HAUREAU, Histoire de la phil. scol., II (Paris, 1880), 2nd part, 281; FERET, La faculte de theologie de Paris, III (Paris, 1896), 125, 273; VALOIS, Jean de Jandun et Marsile de Padoue, auteurs du Defensor pacis (Paris, 1906).