In the school and the monastery at Naples Bruno passed as a matter of course through a training in the Scholastic Philosophy. Before entering the monastery of St. Dominic at fifteen years of age he had studied "humane letters, logic, and dialectic,"[155] and had attended, among other lectures, a private course by Theophilus of Varrano, an Augustine monk and distinguished Aristotelian. From him, probably, Bruno received an impetus towards the study of Aristotle in the original works, if not also in the original tongue, which stood him in admirable stead when he came later to attack the foundations of the vulgar philosophy. He was familiar at first hand with all the main writings of Aristotle.[156] He had read, too, and cites, most of the earlier commentators--Adrastus and Alexander of Aphrodisias, Porphyry, Themistius, Simplicius, and "Philoponus"[157]--as well as the later, the Arabians and other Schoolmen. He had accordingly a more thorough acquaintance with the mind of Aristotle than any of the latter's staunchest supporters in his time: the lack of the historic sense prevented him, however, from taking a just view of the system as a whole: it was not the Aristotle of Greek philosophy whom he rejected, and against whom he wielded the powerful weapons of his armoury, but the Aristotle of his own day,--a living force with which no one could avoid a reckoning, the influence of which was no longer for good, but which formed, as Bruno felt, a barrier against the progressive thought and spirit of the time. In the introductory letter to the _Figuratio Arist. Phys. Auditus_, Bruno gave three reasons for undertaking the work:[158]--(1) "that he might not appear, like so many others, to be taking up the office of censor without a sufficient knowledge of his subject; (2) that he might present to his opponents the philosophy of Aristotle as it really was, for the majority of the Aristotelians admired it rather from their faith in the man Aristotle than from discriminate judgment concerning the principles of the philosophy; (3) that he might seem not an audacious caviller against thoughts that were beyond his depth, but a genuine and legitimate disputant on doctrines that were clear to himself."[159] The name of Aristotle was a charm; his opinion final not in matters of pure philosophy alone, but equally in natural theory; his natural philosophy had been harmonised with scriptural authority, and was the accepted doctrine of the Church. The cry which his critic heard had weight behind it: "You against Aristotle--against so many authorities, so great names? I would rather be in error along with them, than find truth with you!"[160] The danger lay not so much in the error of Aristotle's theory of nature, or of his metaphysical theories, as in his authority; "many of the Peripatetics," Bruno says in the _Cena_, "grow angry, and flush and quarrel about Aristotle, yet do not understand even the meanings of the titles of his books."[161]