11 But the learned men whom We call apologists speedily encountered these teachers of foolish doctrine and, under the guidance of faith, found arguments in human wisdom also to prove that one God, who stands pre-eminent in every kind of perfection, is to be worshiped; that all things were created from nothing by His omnipotent power; that by His wisdom they flourish and serve each their own special purposes. Among these St. Justin Martyr claims the chief place. After having tried the most celebrated academies of the Greeks, he saw clearly, as he himself confesses, that he could only draw truths in their fullness from the doctrine of revelation. These he embraced with all the ardor of his soul, purged of calumny, courageously and fully defended before the Roman emperors, and reconciled with them not a few of the sayings of the Greek philosophers.
Source: Aeterni Patris (Vatican.va)