The fierce polemics and single-handed battles between Irenæus and the Gnostics are too well known to need repetition. They were carried on for over two centuries after the unscrupulous Bishop of Lyons had uttered his last religious paradox. Celsus, the Neo-platonist, and a disciple of the school of Ammonius Saccas, had thrown the Christians into perturbation, and even had arrested for a time the progress of proselytism by successfully proving that the original and purer forms of the most important dogmas of Christianity were to be found only in the teachings of Plato. Celsus accused them of accepting the worst superstitions of Paganism, and of interpolating passages from the books of the Sybils, without rightly understanding their meaning. The accusations were so plausible, and the facts so patent, that for a long time no Christian writer had ventured to answer the challenge. Origen, at the fervent request of his friend, Ambrosius, was the first to take the defense in hand, for, having belonged to the same Platonic school of Ammonius, he was considered the most competent man to refute the well-founded charges. But his eloquence failed, and the only remedy that could be found was to destroy the writings of Celsus themselves.[82] This could be achieved only in the fifth century, when copies had been taken from this work, and many were those who had read and studied them. If no copy of it has descended to our present generation of scientists, it is not because there is none extant at present, but for the simple reason that the monks of a certain Oriental church on Mount Athos will neither show nor confess they have one in their possession.[83] Perhaps they do not even know themselves the value of the contents of their manuscripts, on account of their great ignorance. The dispersion of the Eclectic school had become the fondest hope of the Christians. It had been looked for and contemplated with intense anxiety. It was finally achieved. The members were scattered by the hand of the monsters Theophilus, Bishop of Alexandria, and his nephew Cyril--the murderer of the young, the learned, and the innocent Hypatia![84]