St Thomas Aquinas - The Summa Theologica: Complete Edition

ENCYCLICAL OF POPE LEO XIII
ON THE RESTORATION OF CHRISTIAN PHILOSOPHY

To the Patriarchs, Primates, Archbishops, and
Bishops of the Catholic World in Grace and
Communion with the Apostolic See.

The only-begotten Son of the Eternal Father, who came on earth to bring salvation and the light of divine wisdom to men, conferred a great time be consonant with the dignity of human science.

2. Whoso turns his attention to the bitter strifes of these days and seeks a reason for the troubles that vex public and private life must come to the conclusion that a fruitful cause of the evils which now afflict, as well as those which threaten, us lies in this: that false conclusions concerning divine and human things, which originated and by adding to its strength renders it capable of greater things.

3. Therefore, Divine Providence itself requires that, in calling back the people to the paths of faith and salvation, advantage should be taken of human science also-an approved and wise practice which history testifies was observed by the most illustrious Fathers of the Church. They, indeed, were wont neither to belittle

4. In the first place, philosophy, if rightly made use of by the wise, in a certain way tends to smooth and fortify the road to true faith, and to prepare the souls of But if natural reason first sowed this rich field of doctrine before it was rendered fruitful by the power of Christ, it must assuredly become more prolific after the grace of the Saviour has renewed and added to the native faculties of the human mind. And who does not see that a plain and easy road is opened up to faith by such a method of philosophic study?

6. Its solid foundations having been thus laid, a perpetual and varied service is further required of philosophy, in order that sacred theology may receive

7. Lastly, the duty of religiously defending the truths divinely delivered, and of resisting those who dare oppose them, pertains to philosophic pursuits. Wherefore, it is the glory of philosophy to be esteemed as the bulwark of faith and the strong defense of religion. As Clement of Alexandria testifies, the doctrine of

8. But in order that philosophy may be bound equal to the gathering of those precious fruits which we have indicated, it behooves it above all things never to turn aside from that path which the Fathers have entered upon from a venerable antiquity, and which the Vatican Council solemnly and authoritatively approved. As it is evident that very many truths of the supernatural order which are far beyond the reach of the keenest intellect must be accepted, human reason, conscious of its own infirmity, dare not affect to itself too great powers, nor deny those truths, nor measure them by its own standard, nor interpret them at will; but receive them, rather, with a full and humble faith, and esteem it the highest honor to be allowed to wait upon heavenly doctrines like a handmaid and attendant, and by Gods goodness attain to them in any way whatsoever. But in the case of such doctrines as the human intelligence may perceive, it is equally just that philosophy should make use of its own method, principles, and arguments-not, indeed, in such fashion as to seem rashly to withdraw from the divine authority. But, since it is established that those things which become known by revelation have the force of certain truth, and that those things which war against faith war equally against right reason, the Catholic philosopher will know that he violates at once faith and the laws of reason if he accepts any conclusion which he understands to be opposed to revealed doctrine.

9. We know that there are some who, in their overestimate of the human faculties, maintain that as soon as mans intellect becomes subject to divine authority it falls from its native dignity, of wandering.

10. If, venerable brethren, you open the history of philosophy, you will find all We have just said proved by experience. The philosophers of old who lacked the gift of faith, yet were esteemed so wise, fell into many appalling errors. You know how often among some truths they taught false and incongruous things; what vague and doubtful opinions they held concerning the nature encountered a multitude of most bitter adversaries, who, deriding the Christian dogmas and institutions, maintained that there were many gods, that the material world never had a beginning or cause, and that the course of events was one of blind and fatal necessity, not regulated by the will of Divine Providence.

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.

we add to the number of the great men of whom mention has been made the names of Basil the Great and of the two Gregories, who, on going forth from Athens, that home of all learning, thoroughly equipped with all the harness of philosophy, turned the wealth of knowledge which each had gathered up in a course of zealous study to the work of refuting heretics and preparing Christians.

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.