To meet such skepticism too was one of the undertakings of the renowned Abailard (1079-1142), himself persecuted as a heretic for the arguments with which he sought to guard against unbelief. Of the details of his early life it concerns us here to note only that he studied under Roscelin, and swerved somewhat in philosophy from his master's theoretic Nominalism, which he partly modified on Aristotelian lines, though knowing little of Aristotle. [1390] After his retirement from the world to the cloister, he was induced to resume philosophic teaching; and his pupils, like those of Anselm, begged their master to give them rational arguments on the main points of the faith. [1391] He accordingly rashly prepared a treatise, De Unitate et Trinitate divina, in which he proceeded "by analogies of human reason," avowing that the difficulties were great. [1392] Thereupon envious rivals, of whom he had made many by his arrogance as well as by his fame, set up against him a heresy hunt; and for the rest of his life he figured as a dangerous person. While, however, he took up the relatively advanced position that reason must prepare the way for faith, since otherwise faith has no certitude, [1393] he was in the main dependent on the authority either of second-hand Aristotle [1394] or of the Scriptures, though he partly set aside that of the Fathers. [1395] When St. Bernard accused him of Arianism and of heathenism he was expressing personal ill-will rather than criticizing. Abailard himself complained that many heresies were current in his time [1396]; and as a matter of fact "more intrepid views than his were promulgated without risk by a multitude of less conspicuous masters." [1397] For instance, Bernard Sylvester (of Chartres), in his cosmology, treated theological considerations with open disrespect [1398]; and William of Conches, who held a similar tone on physics, [1399] taught, until threatened with punishment, that the Holy Ghost and the Universal Soul were convertible terms. [1400] This remarkably rational theologian further rejected the literal interpretation of the creation of Eve; in science he adopted the Demokritean doctrine of atoms; and in New Testament matters he revived the old rationalistic heresy that the three Persons of the Trinity are simply three aspects of the divine personality--power, wisdom, and will--which doctrine he was duly forced to retract. It is clear from his works that he lived in an atmosphere of controversy, and had to fight all along with the pious irrationalists who, "because they know not the forces of nature, in order that they may have all men comrades in their ignorance, suffer not that others should search out anything, and would have us believe like rustics and ask no reason." "If they perceive any man to be making search, they at once cry out that he is a heretic." The history of a thousand years of struggle between reason and religion is told in those sentences.