13 But Augustine would seem to have wrested the palm from all. Of a most powerful genius and thoroughly saturated with sacred and profane learning, with the loftiest faith and with equal knowledge, he combated most vigorously all the errors of his age. What topic of philosophy did he not investigate? What region of it did he not diligently explore, either in expounding the loftiest mysteries of the faith to the faithful, or defending them against the full onslaught of adversaries, or again when, in demolishing the fables of the Academicians or the Manichaeans, he laid the safe foundations and sure structure of human science, or followed up the reason, origin, and causes of the evils that afflict man? How subtly he reasoned on the angels, the soul, the human mind, the will and free choice, on religion and the life of the blessed, on time and eternity, and even on the very nature of changeable bodies. Afterwards, in the East, John Damascene, treading in the footsteps of Basil and of Gregory of Nazianzen, and in the West, Boethius and Anselm following the doctrines of Augustine, added largely to the patrimony of philosophy.
Source: Aeterni Patris (Vatican.va)