Summa Theologiae/Encyclical of Leo XIII

For other English-language translations of this work, see Aeterni Patris (Leo XIII).
Summa Theologiae (1893)
by Thomas Aquinas, translated by The Fathers of the English Dominican Province
Encyclical of Leo XIII by Leo XIII
Leo XIII193875Summa Theologiae — Encyclical of Leo XIII1893The Fathers of the English Dominican Province

ENCYCLICAL LETTER


OF


OUR HOLY FATHER


BY DIVINE PROVIDENCE


POPE LEO XIII.


ON


THE RESTORATION OF CHRISTIAN PHILOSOPHY,


ACCORDING TO THE MIND OF


ST. THOMAS AQUINAS, THE ANGELIC DOCTOR


page


To His Venerable Brethren, all the Patriarchs, Primates, Archbishops, and Bishops of the Catholic World, in favour and communion with the Apostolic See,

POPE LEO XIII.

Venerable Brethren,

Health and Apostolic Benediction.

The Only-begotten Son of the Eternal Father appeared on earth to bring salvation and the light of the wisdom of God to the human race. As He was ascending to Heaven He bestowed on the world a blessing, truly great and wondrous, when, commanding His Apostles to 'go and teach all nations,'[1] He left a Church, founded by Himself, as the universal and supreme mistress of all people. Man, whom the truth had set free, was to be kept safe by the truth. Indeed, the fruits of heavenly doctrine, by which salvation was gained for man, could not have endured for long unless Christ our Lord had set up a perpetual teaching authority (magisterium) for the instruction of souls in the faith. This Church, then, not only built on the promises of its Divine Author, but following in His love, has kept His commands. She has always looked to one end, and desired it with great desire; that is, to teach the true religion and wage ceaseless war with error. For this there have been the watchful labours of Bishops, each in his own place; and for this Councils have made laws and decrees. More than all, for this there has been the daily anxiety of the Roman Pontiffs. They are the successors of Blessed Peter, the Prince of the Apostles, in his Primacy, and therefore it is their right and their duty to teach the brethren, and confirm them in the faith.

Now, the Apostle warns us that the faithful of Christ are often deceived in mind 'by philosophy and vain deceit,'[2] and that thus the sincerity of faith is corrupted in men. For this reason the Supreme Pastors of the Church have always held that it is part of their office to advance, with all their power, knowledge truly so called; but at the same time to watch with the greatest care that all human learning shall be imparted according to the rule of the Catholic faith. Especially is this true of 'philosophy,' on which the right treatment of other sciences depends in great measure. We Ourselves spoke to you shortly of this, among other things, Venerable Brothers, when first We addressed you all by an Encyclical Letter. Now, by the importance of this matter, and by the state of the times, We are forced again to write to you, that you may so organize the course of philosophical studies as to insure their perfect correspondence with the gift of Faith, and also their agreement with the dignity of human knowledge.

If anyone look carefully at the bitterness of our times, and if, further, he consider earnestly the cause of those things that are done in public and in private, he will discover with certainty the fruitful root of the evils which are now overwhelming us, and of the evils which we greatly fear. The cause he will find to consist in this—evil teaching about things, human and divine, has come forth from the schools of philosophers; it has crept into all the orders of the State; and it has been received with the common applause of very many. Now, it has been implanted in man by Nature to follow reason as the guide of his actions, and therefore, if the understanding go wrong in anything, the will easily follows. Hence it comes about that wicked opinions in the understanding, flow into human actions and make them bad. On the other hand, if the mind of man be healthy, and strongly grounded in solid and true principles, it will assuredly be the source of great blessings, both as regards the good of individuals and as regards the common weal.

We do not, indeed, attribute to human philosophy such force and authority as to judge it sufficient for the utter shutting out and uprooting of all errors. When the Christian religion was first established by the wondrous light of Faith shed abroad, 'not in the persuasive words of human wisdom,[3] but in showing of the Spirit and power,' the whole world was restored to its primeval dignity. So also now, chiefly from the almighty power and help of God, we may hope that the darkness of error will be taken away from the minds of men, and that they will repent. But we must not despise or undervalue those natural helps which are given to man by the kindness and wisdom of God, Who strongly and sweetly orders all things; and it stands to reason that a right use of philosophy is the greatest of these helps. For God did not give the light of reason in vain to the soul of man, nor does the superadded light of Faith quench, or even lessen, the strength of the understanding. Its effect is far from this. It perfects the understanding, gives it new strength, and makes it fit for greater works. The very nature of the providence of God Himself, therefore, makes it needful for us to seek a safeguard in human knowledge when we strive to bring back the people to Faith and salvation. The records of antiquity bear witness that this method, both probable and wise, was used habitually by the most illustrious Fathers of the Church. They, in truth, were wont to give to reason offices neither few nor small; and these the great Augustine has summed up very shortly: 'Attributing to this science … that by which the life-giving Faith … is begotten, nourished, guarded, and strengthened.'

In the first place, then, if philosophy be rightly and wisely used, it is able in a certain measure to pave and to guard the road to the true Faith; and is able, also, to prepare the minds of its followers in a fitting way for the receiving of revelation. Hence it has not untruly been called by the ancients 'an education leading to the Christian Faith,' 'a prelude and help of Christianity,' 'a schoolmaster for the Gospel.'

In truth, the loving-kindness of God, with regard to the things concerning Himself, has not only made known by the light of Faith many truths beyond the reach of the human understanding, but has also revealed some which are not altogether beyond the power of reason to find out. Such truths, when the authority of God is thus added, become known to all both at once and without any mixture of error. This being so, certain truths, either divinely revealed to us for our belief, or bound up closely with the doctrine of the Faith, were known to wise men among the Gentiles, who were guided only by the light of natural reason. By fitting arguments they vindicated and demonstrated these truths. St. Paul says: 'The invisible things of Him, from the creation of the world, are clearly seen, being understood by the things that are made; His eternal power also and divinity.' Again: 'The Gentiles, who have not the law,' nevertheless 'show the work of the law written in their hearts.'

It is opportune, therefore, in a high degree to use, for the good and the advantage of revealed truth, these other truths that were known even to wise heathens; for thus human wisdom, and the very testimony of the adversaries, give their witness to the Catholic Faith. Further, it is plain that this way of treating the question is not a thing newly devised, but an ancient way very much used by the holy Fathers of the Church. Moreover, these venerable witnesses and guardians of holy traditions see a kind of form of this, and almost a type of it, in one action of the Hebrews; who, as they were going out of Egypt, were commanded to take with them vessels of silver and of gold, with precious garments of the Egyptians. This was done that, by a use suddenly changed, the riches which had ministered to superstition and to rites of ignominy might be dedicated to the service of the true God. Gregory of Neocæsaræa praises Origen for this very reason, that, skilfully gathering together much of the teaching of the Gentiles for the defence of Christian wisdom, and for the destruction of superstition, he used these things as weapons taken from the enemy, and with wondrous power hurled them back. Both Gregory Nazianzen and Gregory of Nyssa approve and praise this manner of teaching in Basil the Great. So also Jerome greatly commends the same thing in Quadratus, a disciple of the Apostles; in Aristides, in Justin, in Irenæus, and in very many others. Augustine also says: 'Do we not see how Cyprian, that doctor of great sweetness and that martyr of great blessedness, was laden with gold and silver and raiment when he went forth from Egypt? Was it not so with Lactantius, with Victorinus, Optatus, and Hilary? Not to speak of the living, was it not so with countless Greeks?' If, then, natural reason produced so rich a crop of learning as this before it was fertilized by the power and working of Christ, much more abundant will be its harvests now, when the grace of the Saviour renews and increases the inborn powers of the mind of man. Is there, indeed, anyone who does not see that a plain and easy road is opened to the Faith by philosophy such as this?

The usefulness, however, which springs from such a way of studying philosophy is not confined within these limits; for in truth severe reproof is given, in the words of the wisdom of God, to the foolishness of those men who, 'by these good things that are seen, could not understand Him that is; neither, by attending to the works, have acknowledged (Him) who was the workman.'

In the first place, then, this great and glorious fruit is gathered from human reason—namely, that it demonstrates the existence of God: 'By the greatness of the beauty and of the creature the Creator of them may be seen, so as to be known thereby.'

In the next place, reason shows that God, in a way belonging only to Himself, excels by the sum of all perfections—that is, by an infinite wisdom, from which nothing can be hidden; and also by a supreme justice which no affection of evil can touch. Hence reason proves that God is not only true, but the very Truth itself, which cannot deceive or be deceived. Further, it is a clear consequence from this that the human reason obtains for the word of God full belief and authority.

In like manner reason declares that the evangelical doctrine has shone as the light from its very beginning, by signs and miracles which are infallible proofs of infallible truth; and that therefore they who receive the Faith by the Gospel do not act rashly, as if they had 'followed cunningly devised fables,' but, by an obedience that is altogether reasonable, submit their understanding and their judgment to the authority of God.

Further, not less than these things in value is it that reason clearly shows us the truth about the Church instituted by Christ. That Church, as the Vatican Synod decreed—'because of the wonderful way in which it spreads; because of its great holiness and inexhaustible fruitfulness in all places; because of its Catholic unity and invincible stability—is in itself a great and perpetual motive of credibility, and an unanswerable argument for its own Divine legation.'

The foundations, then, having been laid in the most solid way, there is needed, further, a use of philosophy, both perpetual and manifold, in order that Sacred Theology may assume and put on the nature, habit, and character of true science. For in this noblest kind of learning it is above everything necessary that the parts of heavenly doctrine, being many and different, should be gathered together, as it were, into one body. Thus they are united by a union of harmony among themselves, all the parts being fittingly arranged, and derived from their own proper principles. Lastly, all of these parts, and each of them, must be strengthened by unanswerable arguments suited to each case.

Nor must we pass by in silence, or reckon of little account, that fuller knowledge of our belief, and, as far as may be, that clearer understanding of the mysteries of the faith which Augustine and other Fathers praised, and laboured to attain, and which the Vatican Synod itself decreed to be very fruitful. Such knowledge and understanding are certainly acquired more fully and more easily by those who, to integrity of life and study of the faith, join a mind that has been disciplined by philosophical culture. Specially is this so since the same Vatican Synod teaches that we ought to seek for understanding of holy dogmas of that kind 'both from the analogy of the things which naturally are known, and also from the way in which the mysteries themselves are related to one another, and also to the last end of man.'

Lastly, it pertains to philosophical discipline to guard with religious care all truths that come to us by Divine tradition, and to resist those who dare to attack them. Now, as regards this point, the praise of philosophy is great, in that it is reckoned a bulwark of the faith, and as a strong defence of religion. 'The doctrine of our Saviour,' as Clement of Alexandria bears witness, 'is indeed perfect in itself, and has need of nothing, forasmuch as it is the power and the wisdom of God. But Greek philosophy, though it does not by its approach make the truth more powerful, has yet been called a fit hedge and ditch for the vineyard, because it weakens the arguments of sophists against the truth, and wards off the crafty tricks of those by whom the truth is attacked.'

In fact, as the enemies of the Catholic name borrow their warlike preparations from philosophic method, when they begin their attacks on religion, so the defenders of the science of God borrow many weapons from the stores of philosophy, by which to defend the dogmas of revelation. Again, we must count it no small victory for the Christian Faith, that human reason powerfully and promptly wards off those very weapons of the enemy which have been got together by the skill of the same human reason for purposes of harm. St. Jerome, writing to Magnus, shows how the Apostle of the Gentiles himself adopted this kind of argument. 'Paul, the leader of the Christian army and the unanswered speaker, pleading a cause for Christ, turns skilfully even a chance inscription into an argument for the faith. From the true David he had learnt indeed how to pluck the weapon from the hands of his enemies, and how to cut off the head of Goliath in his greatest pride with his own sword.'

Nay, more; the Church herself not only advises Christian teachers, but commands them to draw this safeguard from philosophy. For the fifth Lateran Council decreed that 'every assertion contrary to a truth of enlightened faith is altogether false, because the truth cannot possibly contradict the truth': and then it commands doctors of philosophy to apply themselves studiously to the refutation of fallacious arguments; for St. Augustine says: 'If any reason be given against the authority of the Holy Scriptures, then, however subtle it may be, it deceives by its likeness to the truth; for true it cannot possibly be.'

But if philosophy has to be found equal to the work of bringing forth such precious fruits as We have mentioned, it must, above everything, take care never to wander from the path trodden by the venerable antiquity of the Fathers, and approved in the Vatican Synod by the solemn suffrage of authority. It is plainly seen that we must accept many truths in the supernatural order which far surpass the power of any intellect. The human reason, therefore, conscious of its own weakness, must not dare to handle things greater than itself; nor to deny these truths. Again, it must not measure them by its own strength, or interpret them at its own will. Rather let it receive them in the fulness and humility of Faith; reckoning this its greatest honour, that by the goodness of God it is allowed as a handmaid and servant to be busied about heavenly doctrines, and in a certain measure to reach them.

In those heads of doctrine, however, which the human understanding naturally can take in, it is clearly just that philosophy should use its own method, its own principles, and its own arguments: yet not so as to seem to draw itself away with audacity from the authority of God. So, also, when it is plain that things known to us by revelation are most certainly true, and that the arguments brought against the Faith are not in accord with right reason, the Catholic philosopher should bear in mind that he will violate the rights both of Faith and reason, if he embrace any conclusion which he understands to be contrary to revealed doctrine.

We know indeed that there are to be found men who, exalting too highly the powers of human nature, contend that the understanding of man falls from its native dignity when it becomes subject to Divine authority, and that being thus bound, as it were, in a yoke of slavery, it is greatly retarded and hindered from reaching the heights of truth and excellence. Such teaching as that is full of error and falsehood. The end of it is that men, in the height of folly and sinful thanklessness, reject all higher truths. They deliberately cast away the Divine blessings of faith, from which the streams of all good flow, even to civil society. Now, the mind of man is shut up and held in certain bounds, and narrow enough those boundaries are. The consequence is that it falls into many mistakes and is ignorant of many things. On the other hand, the Christian Faith, resting as it does on the authority of God, is the certain teacher of truth. He who follows this guidance is neither entangled in the nets of error nor tossed about on the waves of doubt. Hence the best philosophers are they who join philosophical study with the obedience of the Christian Faith. Then the brightness of Christian truths falls on the mind, and by that brightness the understanding itself is helped. This takes nothing from the dignity of the reason; nay, rather, it adds to the reason a great deal of grandeur and subtlety and strength.

Worthily and most fruitfully do we use the keenness of the understanding when we set ourselves to refute opinions against the Faith, and to prove those things which agree with it. For in disproving errors we ascertain their causes, and then show the falsity of the arguments by which they are bolstered up; while in proving truths we use the force of the reasons by which they are demonstrated with certainty, and by which all prudent men are persuaded. If, then, anyone deny that the riches of the mind are increased and its powers extended by studies and arguments such as these, he must of necessity contend absurdly that the discrimination of truth and falsehood does not in any way help towards intellectual advancement. Rightly, therefore, does the Vatican Synod mention in the following words the great benefits which are received by Faith from reason: 'Faith frees the reason from error, and guards it, and instructs it with a manifold knowledge.' If, then, man were wise, he would not blame Faith as being hostile to reason and natural truths. Rather he would give hearty thanks to God and rejoice greatly that, among so many causes of ignorance and in the midst of such floods of error, the most holy Faith shines brightly on him; for, like a friendly star, that Faith points out to him the harbour of truth, so that he can have no fear of going out of his course.

If, then, Venerable Brothers, you look back at the history of philosophy, you will see that all the words which We have spoken are approved by the facts. Certainly, among the ancient philosophers, living without the Faith, they who were reckoned the wisest erred most harmfully in many things. Though they taught the truth about some things, yet you know how often they taught that which was false and absurd. You know how many uncertain things and doubtful things they handed down about the true nature of the Godhead, the first beginning of creation, the government of the world, God's knowledge of the future, the cause and principle of evil, the last end of man, everlasting beatitude, virtues and vices, as also about other subjects, of which a true and certain knowledge is above everything necessary for man.

On the other hand, the first Fathers and Doctors of the Church understood clearly from the counsel of the will of God that the restorer of human knowledge is Christ, who is the 'power of God and the wisdom of God,' and 'in whom are hidden all the treasures of wisdom and knowledge.' They undertook to examine thoroughly the books of these wise men of old, and to compare their opinions with the teaching of Revelation. With prudent choice they accepted all the true words and wise thoughts with which they met; but the rest they either set right or cast utterly away. As God, in His careful foresight for the defence of His Church against the rage of tyrants, raised up the martyrs, very strong and lavish of their mighty souls; so against philosophers, falsely so called, and against heretics, He raised up men great in wisdom to defend even by the help of human reason the treasure of revealed truth. From the very beginning of the Church, indeed, Catholic doctrine has found enemies most hostile to it, who have derided the dogmas and teachings of Christians. They have laid down such doctrines as these: That there are many gods; that the matter of which the world is made has neither beginning nor cause; that the course of events is governed by a certain blind force and inevitable necessity; and that it is not ruled by the counsel of the providence of God. Wise men, whom we call Apologists, have in due course attacked these teachers of insane doctrine, and, with Faith for their guide, have drawn arguments from human wisdom itself. They have in this way proved that one God, highest in every kind of perfection, is to be worshipped; that all things have been made out of nothing by His almighty power; that they are all sustained by His wisdom; and that each one is directed and moved towards its own end.

Among these, St. Justin Martyr claims for himself the first place. Having frequented the most celebrated schools of learning among the Greeks that he might try what they were, he learned, as he himself acknowledges, that he could drink in the truth with full mouth only from revealed doctrines. These he embraced with all the eagerness of his soul; stripped off the calumnies that hung round them; defended them vigorously and fully before the Roman Emperors; and reconciled with them many sayings of the Greek philosophers. In that time the same work was also done exceedingly well by Quadratus, Aristides, Hermias, and Athenagoras. In the same cause glory not less than theirs was gained by the Bishop of Lyons, Irenæus, the invincible martyr. He refuted with power the wicked teaching of the Easterns, scattered as it was by the help of the Gnostics throughout the bounds of the Roman Empire, St. Jerome says of him: 'He explained . . . the beginnings of heresies one by one, and pointed out from what fountains of the philosophers they flowed.'

Again, there is no one who does not know the disputations of Clement of Alexandria, which the same St. Jerome thus mentions with honour: 'Is there anything that is not learned in them? Is there anything not drawn from the depth of philosophy?' He himself also wrote books of an incredible variety, which are of the greatest use in building up a history of philosophy, in rightly exercising the art of dialectics, and in establishing the harmony that exists between reason and faith. Origen followed him, renowned among the teachers of the Alexandrine school, and deeply learned in the doctrine of the Greeks and the Easterns. He wrote a very great number of books, and spent much labour upon them. Wondrously, just at the right time, they explained the Holy Scriptures, and threw light on our sacred dogmas. It is true that these books, at least in their present state, are not altogether free from errors; yet they embrace great force of teaching, by which natural truths are increased in number and in strength. Tertullian, too, fights against the heretics by the authority of Scripture. Then changing his weapons, he fights against the philosophers with arguments of philosophy. With so much acuteness and learning does he refute them, that he answers them openly and confidently: 'Neither about science nor about learning are we, as you think, on an equal footing.' Arnobius also in his books against the Gentiles, and Lactantius in his Institutions especially, strive earnestly with like eloquence and strength to persuade men to accept the dogmas and commands of Catholic wisdom. They do not overthrow philosophy, according to the way of the Academy; but partly by their own weapons, and partly by weapons taken from the agreement of philosophers among themselves, they convince them. The great Athanasius and Chrysostom, first of preachers, have left writings about the soul of man, about the Attributes of God, and other questions of the greatest moment. These in the judgment of all are so excellent that it seems as if scarcely anything could be added to their subtlety and exhaustiveness. Not to be too prolix in mentioning them one by one, we add to the number of these most illustrious men of whom we have spoken the great Basil and the two Gregories. From Athens, then the home of the highest culture, they went forth equipped with the panoply of philosophy. Having acquired all their riches of learning by most ardent study, they used them to refute the heretic, and to build up the faithful.

But it is Augustine who seems to have borne away the palm from all. With a towering intellect, and a mind full to overflowing of sacred and profane learning, he fought resolutely against all the errors of his age, with the greatest faith and equal knowledge. What teaching of philosophy did he pass over? Nay, what was there into which he did not search thoroughly? Did he not do this when he was explaining to believers the deepest mysteries of the Faith, and defending them against the furious attacks of the adversaries? or when, after destroying the fictions of Academics and Manichæans, he made safe the foundations of human knowledge and their certainty, searching out also to the furthest point the reason and origin and causes of those evils by which man is oppressed? With what copiousness and with what subtlety did he write about the angels, and the soul, and the human mind; about the will and free-will; about religion and the blessed life; about time and eternity; about the nature of all changeable bodies! Afterwards, among the Easterns, John of Damascus followed in the footsteps of Basil and Gregory Nazianzen; while in the West, Boethius and Anselm, setting forth the doctrines of Augustine, greatly enriched the domain of philosophy.

Then the Doctors of the Middle Ages, whom we call Scholastics, set themselves to do a work of very great magnitude. There are rich and fruitful crops of doctrine scattered everywhere in the mighty volumes of the Holy Fathers. The aim of the Scholastics was to gather these together diligently, and to store them up, as it were, in one place, for the use and convenience of those that come after.

What the origin of the Scholastic discipline was, what were also its characteristics and its value, it will be well, Venerable Brothers, to set forth more fully here in the words of a man of the greatest wisdom—our predecessor Sixtus V.: 'By the Divine gift of Him, Who alone gives the spirit of knowledge and wisdom and understanding, and Who, through the ages, according to her needs, enriches His Church with new gifts, and surrounds her with new safeguards, our ancestors, being men exceedingly wise, developed the study of Scholastic Theology. There were especially two glorious Doctors, teachers of this famous science—that is, the angelic St. Thomas, and the seraphic St. Bonaventure. With surpassing abilities, with ceaseless study, with laborious toil and long watchings, they worked it out and adorned it. They arranged it in the very best way, unfolded it brilliantly in many methods, and then handed it on to their successors.'

The knowledge and the exercise of this science of salvation have certainly always brought the very greatest help to the Church; whether it be for the right understanding and interpretation of Scripture, or for reading and expounding the Fathers with greater safety and profit, or for laying bare and answering different errors and heresies. This doctrine flows from the brimming fountain of the Sacred Scriptures, of the Supreme Pontiffs, and of Holy Fathers and Councils. Now, indeed, in these last days, it is in the highest degree necessary to refute heresies and confirm the dogmas of the Catholic faith. For now have come those dangerous times of which the Apostle speaks. Now men, blasphemous, proud, deceivers, go from bad to worse, wandering from the truth themselves and leading others into error. These words might seem to embrace only the Scholastic Theology; but it is plain that they are also to be taken in reference to philosophy and its praise.

Scholastic Theology has splendid gifts, which make it very formidable to enemies of the truth; as the same Pontiff tells us. 'It has,' he says, 'an apt coherence of facts and causes, connected with one another; an order and arrangement, like soldiers drawn up in battle array; definitions and distinctions very lucid; unanswerableness of argument and acute disputations. By these the light is divided from the darkness, and truth from falsehood. The lies of heretics, wrapped up in many wiles and fallacies, being stripped of their coverings, are bared and laid open.' But these great and wondrous gifts can only be found in a right use of that philosophy which the masters of Scholasticism, of set purpose and with wise counsel, were everywhere accustomed to use even in their theological disputations.'

Moreover, it is the proper and singular gift of Scholastic theologians to bind together human knowledge and Divine knowledge in the very closest bonds. For this reason, truly the theology in which they excelled could never have gained so much honour and praise from the judgment of men as it did, if they had used a system of philosophy which was maimed, or imperfect, or shallow.

Now far above all other Scholastic Doctors towers Thomas Aquinas, their master and prince. Cajetan says truly of him: 'So great was his veneration for the ancient and sacred Doctors that he may be said to have gained a perfect understanding of them all.' Thomas gathered together their doctrines like the scattered limbs of a body, and moulded them into a whole. He arranged them in so wonderful an order, and increased them with such great additions, that rightly and deservedly he is reckoned a singular safeguard and glory of the Catholic Church. His intellect was docile and subtle; his memory was ready and enacious; his life was most holy; and he loved the truth alone. Greatly enriched as he was with the science of God and the science of man, he is likened to the sun; for he warmed the whole earth with the fire of his holiness, and filled the whole earth with the splendour of his teaching. There is no part of philosophy which he did not handle with acuteness and solidity. He wrote about the laws of reasoning; about God and incorporeal substances; about man and other things of sense; and about human acts and their principles. What is more, he wrote on these subjects in such a way that in him not one of the following perfections is wanting: a full selection of subjects; a beautiful arrangement of their divisions; the best method of treating them; certainty of principles; strength of argument; perspicuity and propriety in language; and the power of explaining deep mysteries.

Beside these questions and the like, the Angelic Doctor, in his speculations, drew certain philosophical conclusions as to the reasons and principles of created things. These conclusions have the very widest reach, and contain, as it were, in their bosom the seeds of truths wellnigh infinite in number. These have to be unfolded with most abundant fruits in their own time by the teachers who come after him. As he used his method of philosophizing, not only in teaching the truth, but also in refuting error, he has gained this prerogative for himself. With his own hand he vanquished all errors of ancient times; and still he supplies an armoury of weapons which brings us certain victory in the conflict with falsehoods ever springing up in the course of years.

Moreover, carefully distinguishing reason from Faith, as is right, and yet joining them together in a harmony of friendship, he so guarded the rights of each, and so watched over the dignity of each, that, as far as man is concerned, reason can now hardly rise higher than she rose, borne up in the flight of Thomas; and Faith can hardly gain more helps and greater helps from reason than those which Thomas gave her.

For these causes, especially in former days, men of the greatest learning and worthy of the highest praise both in theology and philosophy, having sought out with incredible diligence the immortal writings of Thomas, surrendered themselves to his angelic wisdom, not so much to be taught by his words, as to be altogether nourished by them. It is plain also that nearly all founders and lawgivers of religious Orders have bidden their children study the doctrines of Thomas, and very religiously adhere to them, giving a caution that it will be allowed to none to deviate ever so little from the footsteps of so great a man. To pass by the Dominican family which, as it were, by a right of its own, glories in this greatest of teachers, the statutes of each Order testify that Benedictines, Carmelites, Augustinians, the Society of Jesus, and many other holy Orders, are bound by this law.

Now our mind flies with great delight to those very celebrated universities and schools which formerly flourished in Europe: such as Paris, Salamanca, Alcala, Douai, Toulouse, Louvain, Padua, Bologna, Naples, Coimbra, and very many others. No one is ignorant that the reputation of these universities grew by age; that their opinions were asked when weighty issues were at stake; and that those opinions had great influence everywhere. But it is also well known that, in those illustrious abodes of human learning, Thomas reigned as a ruler in his own kingdom. The minds of all, both teachers and hearers, with wondrous consent found rest in the guidance and authority of one Angelic Doctor.

But further—and this is of greater importance—the Roman Pontiffs, our predecessors, bore witness to the wisdom of Thomas Aquinas with praises singularly strong, and with most abundant testimonies. Clement VI., Nicholas V., Benedict XIII., and others, testify that the whole Church was enlightened by his admirable teaching. Pius V. acknowledges that heresies are confounded and exposed and scattered by his doctrine, and that by it the whole world is daily freed from pestilent errors. Others, with Clement XII., say that most fruitful blessings have flowed from his writings on the whole Church. They affirm also that the same honour has to be given to him as to the greatest Doctors of the Church, such as Gregory and [[Author:Aurelius Ambrosius|]] Ambrose, and Augustine and Jerome. Others did not hesitate to set forth St. Thomas as a standard and teacher to universities and great schools of learning, saying that they might safely follow him. On this point the words of Blessed Urban V. to the University of Toulouse seem to be most worthy of mention: 'It is our will, and by the authority of these letters we enjoin on you, that you follow the doctrine of Blessed Thomas as true and Catholic, and strive to unfold it with your whole strength.' This example of Urban was followed by Innocent XII. in the University of Louvain, and by Benedict XIV. in the Dionysian College of Granada. To these judgments of the Pontiffs about Thomas there is added, as a crown, the testimony of Innocent VI.: 'His doctrine above all other doctrine, with the one exception of the Holy Scriptures, has such a propriety of words, such a method of explanation, such a truth of opinions, that no one who holds it will ever be found to have strayed from the path of truth; whereas anyone who has attacked it has always been suspected as to the truth.

Moreover, Œcumenical Councils, made glorious by the flower of wisdom gathered from the whole world, always strove with great care to give singular honour to Thomas Aquinas. In the Councils of Lyons, of Vienne, of Florence, of the Vatican, you may say that Thomas was present at the deliberations and decrees of the Fathers, and almost that he presided at them, contending against the errors of Greeks and heretics and rationalists, with a power from which there was no escape, and with a most auspicious result.

But we now come to the greatest glory of Thomas—a glory which is altogether his own, and shared with no other Catholic Doctor. In the midst of the Council of Trent, the assembled Fathers so willing it, the Summa of Thomas Aquinas lay open on the altar, with the Holy Scriptures and the decrees of the Supreme Pontiffs, that from it might be sought counsel and reasons and answers.

Lastly, another crown seems to have been kept for this peerless man—that is, the way in which he extorts homage. praise, and admiration even from the enemies of the Catholic name. It is well known that there have not been wanting heresiarchs who openly said that, if the doctrine of Thomas Aquinas could only be got rid of, they could 'easily give battle to other Catholic Doctors, and overcome them, and so scatter the Church.' A vain hope indeed, but no vain testimony!

For these reasons, Venerable Brothers, so often as We look at the goodness, the force, and the exceedingly great usefulness of that philosophical doctrine in which our fathers took such delight. We judge that it has been rashly done when this doctrine has not always, and everywhere, been held in its own rightful honour. Especially do We judge this to be the case, since it is plain that long use and the judgment of the greatest men, and, what is more than all, the consent of the Church, have favoured the Scholastic method. Here and there a certain new kind of philosophy has taken the place of the old doctrine; and because of this, men have not gathered those desirable and wholesome fruits which the Church and civil society itself could have wished. The aggressive innovators of the sixteenth century have not hesitated to philosophize without any regard whatever to the Faith, asking, and conceding in return, the right to invent anything that they can think of, and anything that they please. From this it quickly followed, of course, that systems of philosophy were multiplied beyond all reason, and that there sprang up conflicting opinions and diverse opinions even about some of the chief things which are within human knowledge. From a multitude of opinions men very often pass to uncertainty and doubt; while there is no one who does not see how easily their minds glide from doubt into error.

But, since man is drawn by imitation, we have seen these novelties lay hold of the minds of some Catholic philosophers, who, undervaluing the inheritance of ancient wisdom, have chosen rather to invent new things than to extend and perfect the old by new truths, and that certainly with unwise counsel, and not without loss to science; for such a manifold kind of doctrine has only a shifting foundation, resting as it does on the authority and will of individual teachers. For this reason it does not make philosophy firm and strong and solid, like the old philosophy, but, on the contrary, makes it weak and shallow.

When We say this, however, We do not condemn those learned and able men who bring their industry and their knowledge, and the riches of new discoveries, to the aid of philosophy; for We clearly see that such a course tends to the increase of learning. But with great care we must guard against spending the whole of our attention, or even the chief part of it, on such studies as these, and on such instruction.

Let the same judgment be formed about Sacred Theology. This may well be aided and illustrated by many helps of erudition; but it is altogether necessary that it should be treated in the weighty manner of the Scholastics, in order that it may continue to be the 'unassailable bulwark of the faith,' by the forces of reason and revelation thus united in it.

Students of philosophy, therefore, not a few, giving their minds lately to the task of setting philosophy on a surer footing, have done their utmost, and are doing their utmost, to restore to its place the glorious teaching of Thomas Aquinas, and to win for it again its former renown.

That many of your order. Venerable Brothers, are with like will following promptly and cheerfully in the same path, We know to the great gladness of Our heart. While We praise these much, We exhort them to go on in the way that they have begun. To the rest of you, one by one, We give this word of counsel: there is nothing which We have longer wished for and desired than that you should give largely and abundantly to youths engaged in study the pure streams of wisdom which flow from the Angelic Doctor as from a perennial and copious spring.

Our reasons for wishing this so earnestly as We do are many.

First, in our times, the Christian Faith is commonly opposed by the wiles and craft of a certain deceitful kind of wisdom. All young men, therefore, and especially those who are growing up as the hope of the Church, ought to be fed with healthful and strong food of doctrine. Thus, being mighty in strength, and possessing an armoury in which all needful weapons may be found, they will learn by experience to treat the cause of religion with power and wisdom, according to the admonition of the Apostle, 'being ready always to satisfy everyone that asketh you a reason of that hope which is in you': and being 'able to exhort in sound doctrine and to convince the gainsayers.'

Next, there are many who, with minds alienated from the Faith, hate all Catholic teaching, and say that reason alone is their teacher and guide. To heal these men of their unbelief, and to bring them to grace and the Catholic Faith, We think that nothing, after the supernatural help of God, can be more useful in these days than the solid doctrine of the Fathers and the Scholastics. They teach firm foundations of Faith, its Divine origin, its certain truth, the arguments by which it is commended to men, the benefits that it has conferred on the human race, and its perfect harmony with reason. They teach all such truths with a weight of evidence and a force that may well persuade even minds unwilling and hostile in the highest degree.

Again, we all see the great dangers which threaten family life, and even civil society itself, because of the pestilence of perverse opinions. Truly all civil society would be much more tranquil and much safer if healthier teaching were given in universities and schools; a doctrine more in unison with the perpetual teaching office (magisterium) of the Church, such as is contained in the volumes of Thomas Aquinas. He disputes about the true nature of liberty, which, in these days, is passing into lawlessness; about the Divine origin of all authority; about laws and their binding force; about the paternal and just government of sovereign princes, with our obedience to higher powers, and the common love that should be among all. The words of Thomas about these things, and others of a like nature, have the greatest strength, indeed a resistless strength, to overthrow the principles of this new jurisprudence, which is manifestly dangerous to the peaceful order of society and to public safety.

Lastly, from the restoration of philosophical teaching as it has been set forth by Us, all human sciences ought to gather hope of improvement, and the promise of a very great safeguard. For from philosophy, as from a guiding wisdom, the beneficent arts have hitherto derived a healthy method and a right measure. They have, moreover, drunk a vital spirit from it as from a common fountain of life. It is proved by fact and constant experience that the liberal arts have been most flourishing when the honour of philosophy has stood inviolate, and when its judgment has been held for wisdom: but that they have lain neglected and almost obliterated when declining philosophy has been enveloped in errors and absurdities.

Hence, also, the physical sciences, which now are held in so much repute, and everywhere draw to themselves a singular admiration, because of the many wonderful discoveries made in them, would not only take no harm from a restoration of the philosophy of the ancients, but would derive great protection from it. For the fruitful exercise and increase of these sciences it is not enough that we consider facts and contemplate Nature. When the facts are well known we must rise higher, and give our thoughts with great care to understanding the nature of corporeal things, as well as to the investigation of the laws which they obey, and of the principles from which spring their order, their unity in variety, and their common likeness in diversity. It is marvellous what power and light and help are given to these investigations by Scholastic philosophy, if it be wisely used.

On this point it is well to call one thing to your minds. It is only by the highest injustice that any jealousy of the progress and increase of natural sciences is laid, as a fault, at the door of that philosophy. When the Scholastics, following the teaching of the Holy Fathers, everywhere taught out their anthropology that the human understanding can only rise to the knowledge of immaterial things by things of sense, nothing could be more useful for the philosopher than to investigate carefully the secrets of Nature, and to be conversant, long and laboriously, with the study of physical science. Indeed, they themselves prove this by their works. Thomas, and Blessed Albert the Great, and other princes of the Scholastics, did not so give themselves up to the study of philosophy, as to have little care for the knowledge of natural things. Nay, on this matter there are not a few of their words and discoveries which modern teachers approve and acknowledge to be in harmony with truth. Besides, in this very age, many distinguished teachers of physical sciences openly bear witness that there is no contradiction, truly so called, between the certain and proved conclusions of recent physics, and the philosophical principles of the Schools.

We, therefore, while We declare that everything wisely said should be received with willing and glad mind, as well as everything profitably discovered or thought out, exhort all of you, Venerable Brothers, with the greatest earnestness to restore the golden wisdom of St. Thomas, and to spread it as far as you can, for the safety and glory of the Catholic Faith, for the good of society, and for the increase of all the sciences. We say the wisdom of St. Thomas; for it is not by any means in our mind to set before this age, as a standard, those things which may have been inquired into by Scholastic Doctors with too great subtlety; or anything taught by them with too little consideration, not agreeing with the investigations of a later age; or, lastly, anything that is not probable.

Let, then, teachers carefully chosen by you do their best to instil the doctrine of Thomas Aquinas into the minds of their hearers; and let them clearly point out its solidity and excellence above all other teaching. Let this doctrine be the light of all places of learning which you may have already opened, or may hereafter open. Let it be used for the refutation of errors that are gaining ground.

But lest the false should be drunk instead of the true; or lest that which is unwholesome should be drunk instead of that which is pure; take care that the wisdom of Thomas be drawn from his own fountain, or at any rate from those streams which, in the certain and unanimous opinion of learned men, yet flow whole and untainted, inasmuch as they are led from the fountain itself. Take care, moreover, that the minds of the young be kept from streams which are said to have flowed from thence, but in reality have been fed by unhealthy waters from other springs.

Well do we know that all our work will be vain, unless, Venerable Brothers, He bless our common efforts, Who in the Divine Scriptures is called the 'God of all knowledge.' By those same Scriptures we are warned, that 'every best gift and every perfect gift is from above, coming down from the Father of lights.' Again, 'If any of you want wisdom, let him ask of God, who giveth to all men abundantly and upbraideth not; and it shall be given him.'

In this matter, then, let us follow the example of the Angelic Doctor, who never began to read or to write without seeking for God's help by prayer; and who in simplicity acknowledged that all his learning had come to him, not so much from his own study and toil, as immediately from God. With humble and united prayer, therefore, let us all together beseech God fervently to pour out the spirit of knowledge and understanding on the sons of the Church, and to open their minds to the understanding of wisdom.

Also, that we may receive more abundant fruits of the goodness of God, use that patronage which is most powerful with Him; that is, the patronage of the Blessed Virgin Mary, who is called the Seat of Wisdom. Secure also, as intercessors, Blessed Joseph, the pure Spouse of the Virgin; and Peter and Paul, the chiefs of the Apostles, who renewed the whole world with truth, when it was corrupted by the uncleanness and the contagion of errors, and who filled it with the light of the wisdom which is from Heaven.

Lastly, in hope, trusting to the help of God and relying on your pastoral zeal, to all of you, Venerable Brothers, to all the clergy, and all the people committed to the care of each, we give, with great love in the Lord, our Apostolical blessing, the earnest of heavenly gifts, and the witness of our special goodwill.

Given at Rome, at St. Peter's, this 4th day of August, 1879, in the second year of our Pontificate.

LEO, PP. XIII.

  1. Matt. xxviii. 19.
  2. Col. ii. 8.
  3. I Cor. ii. 4.