“Sed tamen considerandum est in scientiis philosophicis, quod inferiores scientiae nec probant sua principia, nec contra negantem principia disputant, sed hoc relinquunt superiori scientiae: suprema vero inter eas, scilicet metaphysica, disputat contra negantem sua principia, si adversarius aliquid concedit: si autem nihil concedit, non potest cum eo disputare, potest tamen solvere rationes ipsius. Unde sacra scriptura (_i.e._ Theology), cum non habeat superiorem, disputat cum negante sua principia: argumentando quidem, si adversarius aliquid concedat eorum quae per divinam revelationem habentur; sicut per auctoritates sacrae doctrinae disputamus contra hereticos, et per unum articulum contra negantes alium. Si vero adversarius nihil credat eorum quae divinitus revelantur, non remanet amplius via ad probandum articulos fidei per rationes, sed ad solvendum rationes, si quas inducit, contra fidem. Cum enim fides infallibili veritati innitatur, impossibile autem sit de vero demonstrari contrarium, manifestum est probationes quae contra fidem inducuntur, non esse demonstrationes, sed solubilia argumenta.”[272] Of a different intellectual temperament was John of Fidanza, known as St. Bonaventura.[273] He also was born and passed his youth in Italy. This sainted General of the Franciscan Order was a few years older than the great Dominican, who was his friend. Both doctors died in the year 1274. Bonaventura’s powers of constructive reasoning were excellent. His diction is clear and beautiful, and eloquent with a spiritual fervour whenever the matter is such as to evoke it. His account of how he came to write his famous little _Itinerarium mentis in Deum_ is full of temperament. “Cum igitur exemplo beatissimi patris Francisci hanc pacem anhelo spiritu quaererem, ego peccator, qui loco ipsius patris beatissimi post eius transitum septimus in generali fratrum ministerio per omnia indignus succedo; contigit, ut nutu divino circa Beati ipsius transitum, anno trigesimo tertio ad montem Alvernae tanquam ad locum quietum amore quaerendi pacem spiritus declinarem, ibique existens, dum mente tractarem aliquas mentales ascensiones in Deum, inter alia occurrit illud miraculum, quod in praedicto loco contigit ipsi beato Francisco, de visione scilicet Seraph alati ad instar Crucifixi. In cuius consideratione statim visum est mihi, quod visio illa praetenderet ipsius patris suspensionem in contemplando et viam, per quam pervenitur ad eam.”[274] And Bonaventura at the end of his _Itinerarium_ speaks of the perfect passing of Francis into God through the very mystic climax of contemplation, concluding thus: