St. Thomas Aquinas and the Thirteenth Century | Josef Pieper | From the opening chapter of Guide to Thomas Aquinas | January 28th | Ignatius Insight
So bound up is the life of St. Thomas Aquinas with the thirteenth century that the year in which the century reached its mid-point, 1250, was likewise the mid-point of Thomas' life, though he was only twenty-five years old at the time and still sitting at the feet of Albertus Magnus as a student in the Monastery of the Holy Cross in Cologne. The thirteenth century has been called the specifically "Occidental" century. The significance of this epithet has not always been completely clarified, but in a certain sense I too accept the term. I would even assert that the special quality of "Occidentality" was ultimately forged in that very century, and by Thomas Aquinas himself. It depends, however, on what we understand by "OccidentaIity." We shall have more to say on this matter.
There exists the romantic notion that the thirteenth century was an era of harmonious balance, of stable order, and of the free flowering of Christianity. Especially in the realm of thought, this was not so. The Louvain historian Fernand van Steenberghen speaks of the thirteenth century as a time of "crisis of Christian intelligence";  and Gilson comments: "Anybody could see that a crisis was brewing." 
What, in concrete terms, was the situation? First of all we must point out that Christianity, already besieged by Islam for centuries, threatened by the mounted hordes of Asiatics (1241 is the year of the battle with the Mongols at Liegnitz)—that this Christianity of the thirteenth century had been drastically reminded of how small a body it was within a vast non-Christian world. It was learning its own limits in the most forceful way, and those limits were not only territorial. Around 1253 or 1254 the court of the Great Khan in Karakorum, in the heart of Asia, was the scene of a disputation of two French mendicant friars with Mohammedans and Buddhists. Whether we can conclude that these friars represented a "universal mission sent forth out of disillusionment with the old Christianity,"  is more than questionable. But be this as it may, Christianity saw itself subjected to a grave challenge, and not only from the areas beyond its territorial limits.
For a long time the Arab world, which had thrust itself into old Europe, had been impressing Christians not only with its military and political might but also with its philosophy and science. Through translations from the Arabic into Latin, Arab philosophy and Arab science had become firmly established in the heart of Christendom—at the University of Paris, for example. Looking into the matter more closely, of course, we are struck by the fact that Arab philosophy and science were not Islamic by origin and character. Rather, classical ratio, epitomized by Aristotle, had by such strangely involved routes come to penetrate the intellectual world of Christian Europe. But in the beginning, at any rate, it was felt as something alien, new, dangerous, "pagan."
During this same period, thirteenth-century Christendom was being shaken politically from top to bottom. Internal upheavals of every sort were brewing. Christendom was entering upon the age "in which it would cease to be a theocratic unity,"  and would, in fact, never be so again. In 1214 a national king (as such) for the first time won a victory over the Emperor (as such) at the Battle of Bouvines. During this same period the first religious wars within Christendom flared up, to be waged with inconceivable cruelty on both sides. Such was the effect of these conflicts that all of southern France and northern Italy seemed for decades to be lost once and for all to the corpus of Christendom. Old monasticism, which was invoked as a spiritual counterforce, seems (as an institution, that is to say, seen as a whole) to have become impotent, in spite of all heroic efforts to reform it (Cluny, Cîteaux, etc.). And as far as the bishops were concerned—and here, too, of course, we are making a sweeping statement—an eminent Dominican prior of Louvain, who incidentally may have been a fellow pupil of St. Thomas under Albertus Magnus in Cologne, wrote the following significant homily: In 1248 it happened at Paris that a cleric was to preach before a synod of bishops; and while he was considering what he should say, the devil appeared to him. "Tell them this alone," the devil said. "The princes of infernal darkness offer the princes of the Church their greetings. We thank them heartily for leading their charges to us and commend the fact that due to their negligence almost the entire world is succumbing to darkness." 
But of course it could not be that Christianity should passively succumb to these developments. Thirteenth-century Christianity rose In Its own defense, and in a most energetic fashion. Not only were great cathedrals built in that century; It saw also the founding of the first universities. The universities undertook, among other things, the task of assimilating classical ideas and philosophy, and to a large extent accomplished this task.
There was also the whole matter of the "mendicant orders," which represented one of the most creative responses of Christianity. These new associations quite unexpectedly allied !hemselves with the institution of the university. The most important university teachers of the century, in Paris as well as in Oxford, were all monks of the mendicant orders. All in all, nothing seemed to be "finished"; everything had entered a state of flux. AIbertus Magnus voiced this bold sense of futurity in the words: Scientiae demonstrativae non omnes factae sunt, sed plures restant adhuc inveniendae; most of what exists in the realm of knowledge remains still to be discovered. 
The mendicant orders took the lead in moving out into the world beyond the frontiers of Christianity. Shortly after the middle of the century, while Thomas was writing his Summa Against the Pagans, addressed to the mahumetistae et pagani,  the Dominicans were founding the first Christian schools for teaching the Arabic language. I have already spoken of the disputation between the mendicant friars and the sages of Eastern faiths in Karakorum. Toward the end of the century a Franciscan translated the New Testament and the Psalms into Mongolian and presented this translation to the Great Khan. He was the same Neapolitan, John of Monte Corvino, who built a church alongside the Imperial Palace in Peking and who became the first Archbishop of Peking.
This mere listing of a few events, facts, and elements should make it clear that the era was anything but a harmonious one. There is little reason for wishing for a return to those times—aside from the fact that such wishes are in themselves foolish.
Nevertheless, it may be said that in terms of the history of thought this thirteenth century, for all its polyphonic character, did attain something like harmony and "classical fullness." At least this was so for a period of three or four decades. Gilson speaks of a kind of "serenity."  And although that moment in time is of course gone and cannot ever again be summoned back, it appears to have left its traces upon the memory of Western Christianity, so that it is recalled as something paradigmatic and exemplary, a kind of ideal spirit of an age which men long to see realized once more, although under changed conditions and therefore, of course, in some altogether new cast.
Now as it happens, the work of Thomas Aquinas falls into that brief historical moment. Perhaps it may be said that his work embodies that moment. Such, at any rate, is the sense in which St. Thomas' achievement has been understood in the Christian world for almost seven hundred years; such are the terms in which it has repeatedly been evaluated. Not by all, to be sure (Luther called Thomas "the greatest chatterbox" among the scholastic theologians ); but the voices of approbation and reverence have always predominated. And even aside from his written work, his personal destiny and the events of his life unite virtually all the elements of that highly contradictory century in a kind of "existential" synthesis. We shall now speak of these matters at greater length, and in detail.
First of all, a few remarks regarding books.
The best introduction to the spirit of St. Thomas is, to my mind, the small book by G. K. Chesterton, St. Thomas Aquinas.  This is not a scholarly work in the proper sense of the word; it might be called journalistic—for which reason I am somewhat chary about recommending it. Maisie Ward, co-owner of the British-American publishing firm which publishes the book, writes in her biography of Chesterton  that at the time her house published it, she was seized by a slight anxiety. However, she goes on to say, Étienne Gilson read it and commented: "Chesterton makes one despair. I have been studying St. Thomas all my life and I could never have written such a book." Still troubled by the ambiguity of this comment, Maisie Ward asked Gilson once more for his verdict on the Chesterton book. This time he expressed himself in unmistakable terms: "I consider it as being, without possible comparison, the best book ever written on St. Thomas. . . . Everybody will no doubt admit that it is a 'clever' book, but the few readers who have spent twenty or thirty years in studying St. Thomas Aquinas, and who, perhaps, have themselves published two or three volumes on the subject, cannot fail to perceive that the so-called 'wit' of Chesterton has put their scholarship to shame. . . . He has said all that which they were more or less clumsily attempting to express in academic formulas." Thus Gilson. I think this praise somewhat exaggerated; but at any rate I need feel no great embarrassment about recommending an "unscholarly" book.
 Fernand van Steenberghen, Le XIIIe siècle. In Forest, van Steenberghen, and de Gandillac, Le Mouvement doctrinal du Xle au XIVe siècle. Fliche-Martin, Histoire de l'Eglise vol. 13 (Paris, 1951), p. 303.
 Etienne Gilson, History of Christian Philosophy in the Middle Ages (London and New York, 1955), p. 325.
 Friedrich Reer, Europäische Geistesgeschichte (Stuttgart, 1953), p.147.
 Marie-Dominique Chenu, Introduction à l'etude de St. Thomas d'Aquin (Paris—Montreal, 1950), p. 13.
 Gustav Schnürer, Kirche und Kultur im Mittelalter (Paderborn, 1926), II, p. 441.
 Liber primus Posteriorum Analyticorum, tract. 1, cap. 1 Opera Omnia. Ed. A. Borgnet (Paris, 1890), tom. 2, p. 3.
 C. G. 1,2.
 Gilson, History, p. 325.
 Joseph Lortz, Die Reformation in Deutschland (Freiburg im Breisgau, 1939), I, p. 352.
 Heidelberg, 1956.
 Maisie Ward, Gilbert Keith Chesterton (New York, 1943), p. 620.
Editor's note: Pieper's book was originally published in English in 1962 by Pantheon Books. The Ignatius Press edition was published in 1991.