398. John of Jandun or John of Ghent. -- The recognized leader of Parisian Averroïsm in the fourteenth century was JOHN OF JANDUN or JOHN OF GHENT (de Genduno, de Ganduno^{1}). There is some doubt about the identity of the philosopher who composed the influential writings attributed to John of Jandun. Historians have confounded John of Jandun -- magister artistarum in the Navarre College at Paris, afterwards master of theology, author of the De Laudibus Parisius (1323) and of the Defensor Pacis, forced to take refuge on account of his political theories, in company with Marsilius of Padua, at the court of Louis of Bavaria^{2} -- with John of Ghent, a quiet theologian who was pastor of Kieldrecht and Canon of Paris. This latter John of Ghent was teaching theology at Paris in 1303, whereas in 1316 John of Jandun had not yet become master of arts.

Which of those two men was the Averroïst leader? It is not easy to determine. An argument for John of Jandun may be drawn from the fact that he received through Marsilius of Padua, and expounded in his lectures, a treatise (Expositio Problematum Aristotelis) by the Italian Averroïst, Petri D'Abano. However this may be, the commentaries on the De Anima, the De Coelo et Mundo, the Metaphysics and the Physics of Aristotle, on the Expositio and on the Sermo de Substantia Orbis of Averroës,^{3} are certainly all stones of the same edifice, carved by the same workman. And they contain the most typical Averroism. There is not a page of them free from the blind Ipsedixitism that robbed this system of all freshness and originality. John of Jandun declares himself the monkey of Aristotle and Averroës,^{4} the imperfect imitator of the perfect work of those two great geniuses; blaming anyone who would dare to hint that there are contradictions in the Commentator. John of Jandun wrote dissertations on all the leading doctrines of Latin Averroïsm (339): he proves the eternity of the world and of movement,^{5} the necessary realization of possibles,^{6} the absence of all evil in eternal beings,^{7} the impossibility of God's creating beings, or knowing anything except Himself.^{8} In psychology he teaches the separate, eternal existence of one, single, human intellect: "Unus substantialiter est omnium intellectus, non plurificabilis seu multiplicabilis ad corporum multiplicationem . . . "^{9} The intellectual soul cannot, therefore, be the unique and single form of the composite human individual: it is really distinct from the sensible soul;^{10} and although this way of explaining the constitution of our being involves the author in a multitude of difficulties, he declares it more satisfactory than the scholastic theory.^{11} In ethics, John confounds the free with the merely voluntary, in order the better to defend psychological determinism: "Liberum arbitrium est quod est gratia sui ergo liberum habet illud quod est gratia sui, licet ex necessitate agat".^{12} Here certainly is anti-scholasticism. And the author's efforts to protect his faith as a Christian are decidedly interesting. Although I hold as true before my reason all the teachings of Averroïsm, nevertheless, he explains to us, I consider them false before my religion: herein, as St. Augustine informs us, lies the merit of our faith. "Ibi cessat meritum, ubi ratio praebet experimentum." And, to cap the climax: The wonderful omnipotence of God knows no limits, not even the impossible. "Responderem breviter concedendo tamquam possibilia apud Deum omnia ad quae illae rationes deducunt tamquam impossibilia."^{13} This discovery apparently puts him at ease and gives him the illusion of reconciling the irreconcilable.^{14}

After this, it is not surprising to find that John of Jandun or John of Ghent did all in his power to lessen the great repute in which St. Thomas was held at the University of Paris. He belittles and affects to despise the commentaries of the great interpreter "qui putatur fuisse melior inter Latinos," and concludes thus: "Sed re vera salva reverentia hujus hominis, ipse inaniter laborat contra commentato rem sicut et in aliis philosophicis in quibus ei objicit. . . . Dico quod ego non credo ei in hoc, sicut nec in aliis conclusionibus philosophicis in quibus contradicit commentatori."^{15} John was one of the leaders of the Averrorït school: he himself frequently refers in his writings to monographs written by one or other of his confederates ("socii") on special questions in the Averroïstic philosophy.

{1} We find both forms in the manuscripts.

{2} At the Court of Louis of Bavaria, they drew up, against Pope John XXII., the Defensor Pacis (1327), which was condemned in the year of its publication. D'ARGENTRÉ (op. cit., i., p. 397) quotes, under the year 1376, the words: "adversus errores Marsilli de Padua et J. de Janduno in Gallicum sermonem translatos".

{3} We have been unable to verify this of the Quodlibeta attributed to John of Jandun. The author of the commentary on the De Anima refers incidentally to many other works from his pen: Quaestiones de Formatione Foetus, Quaestiones de Gradibus et Pluralitate Formarum, Tractatus de Specie Intelligibili, Duo Tractatus de Sensu Agente; stating also that one of the latter was his first work.

{4} Comm. on the Metaph. (Venice, 1525), f. 84.

{5} "Totum mundum ingenitum secundum totum necesse est esse" (De Coelo et Mundo, I. i., q. 29; Phys., I. viii., q. 3).

{6} Metaph., 1. ix., q. 5: "Utrum aliquid sit possibile in rerum natura quod nunquam erit". The author replies in the negative.

{7} "Ibid., 1. ix., q. 12.

{8} Ibid., f. 142, c. 3.

{9} De Anima, l. iii., q. 57.

{10} "Anima sensitiva et intellectiva sunt diversae substantiae et formae" (ibid., l. iii., q. 12).

{11} "Quamvis igitur difficile sit intelligere quomodo ex materia et forma subsistente, non inhaerente, fiat unum, tamen multo difficilius est hoc intelligere de anima intellectiva et humano corpore secundum positionem catholicam quam secundum positionem commentatoris" (ibid., f. 65).

{12} De Coelo et Mundo, f. 22.

{13} De Anima, f. 66, c. i.

{14} " Quod si alicui primo adspectu non videretur sufficere ad solutiones rationum, non tamen propter hoc debet conturbari, quia certum est quod auctoritas divina majorem fidem debet facere quam quaecumque ratio humanitus inventa" (De Anima, f. 60, c. I). And in Metaph., f. 13, c. I: "Credo melius esse quoad salutem animarum nostrarum assentire et simpliciter credere, quam rationibus sophisticis ea probare et rationes ex sensibus electas debiliter et minus evidenter annotare".

{15} Physics, f. 96 c. 4; f. 97, C. 2.