tended like ii luic;e crescent from Spain over Nortlierri Africa, Kgypt, Palestine, Arabia, Persia, and Syria, to the eastern part of Asia Minor. The danger which this fanatic religion offered to Christian faith, in countries where the two religions came in contact, was not to be treated lightly. And so wc find a series of apologies written to uphold the truth of Christianity in the face of Moslem errors. Perhaps the earliest was the "Discussion between a Saracen and a Christian" composed by St. John I)ama.scene (about 750). In this apology he vindicates the dogma of the Incarnation against the rigid and fatal- istic conception of God taught by Mohammed. He also deinoiLstratos the superiority of the religion of Christ, pointing out the grave defects in Mohammed's life and teaching, and showing the Koran to be in its best parts but a feeble imitation of the Sacreil Scriptures. Other apologies of a similar kind were composed by Peter the Venerable in the twelfth, and by Raymond of Martini in the thirteenth century. Hardly less dangerous to Christian faith was the rationalistic philosophy of Islamism. The Arabian conquerors had learned from the Syrians the arts and sciences of the Greek world. Tiiey became es- pecially proficient in medicine, mathematics, and philosophy, for the study of which they erected in every part of their domam schools and libraries. In the twelfth century .Moorish Spain had nineteen col- leges, and their renown attracted hundreds of Chris- tian scholars from every part of Europe. Herein lay a grave menace to Christian orthodoxy, for the phil- osophy of Aristotle as taught in these schools had become thoroughly tinctured with Arabian panthe- ism and rationalism. The pecviliar tenet of the cele- brated Moorish philosopher Averroes was much in vogue, namely: that philosophy and religion are two independent spheres of thought, so that what is true in the one may be false in the other. Again, it w:is commonly taught that faith is for the masses who cannot think for them.-iolvcs, but philosophy is a higher form of knowledge which noble minds should seek to acqviire. .\mong the fundamental dogmas denied by the Arabian philosophers were creation, providence, and immortality. To vindicate Chris- tianity against Mohammedan rationalism, St. Thomas composed (1261-64) his philosophical "Summa con- tra Gentiles", in four books. In this great apology the respective claims of reason and faith are care- fully distinguished and harmonized, and a systematic demonstration of the grounds of faith is built up with arguments of reason and authority such as appealed directly to the minds of that day. In treating of (iod, providence, creation and the future life, St. Thomas refutes the chief errors of the Arabian, Jew- ish, and (ircck philosophers, and shows that the gen- uine teaching of .\ristotlo confirms the great truths of religion. Three apologies composed in much the same spirit, but Ijclonging to a later age, may be mentioned here. The one is the fine work of Louis Viv(5s, " De Vcritate Fidei Christ ian:c I.ibri V" (about 1.530). After treating the principles of nat- ural theology, the Incarnation, and Hcdcmption, he gives two dialogues, one between a Christian and a Jew, the other between a Christian and a Mohain- merlan, in which he shows the superiority of tho Christian religion. Similar to this is the apology of the celebrated Dutch theologian Grotius, " De Veri- tate Ileligionis Christiana-" (1627). It is in six books. An able treat i.'^e on natural theology is fol- lowed by a demonstration of the tnith of Chri.stianity base<l on the life and miracles of Jesus, the holiness of His teaching, and the wonderful propagation of His religion. In proving the authenticity and trust- worthiness of the Sacred Scriptures, Grotius appeals largely to internal evidence. The latter part of the work is devoted to a refutation of paganism, Juda- ism, and Mohammedanism. An apology on some-
what similar lines is that of the Huguenot, Philip de Mornay, "De la v<Srit(5 de la religion chr6tienne" (1.'579). It is the first apology of note that was written in a modern tongue.
Thihd Peuiou. Catholicism in coNFi.irr wrrii PHOTK.STANTISM. The outbreak of Protestantism in the beginning of the sixteenth century, and its re- jection of many of the fundamental features of Ca- tholicism, called forth a mass of controversial apolo- getic literature. It vnia not, of course, the first time that the principles of Catholic belief had been ques- tioned with reference to Christian orthodo.\y. In the early ages of the Church heretical sects, assuming the right to profess allegiance and fidelity to the spirit of Christ, had given occasion to St. Irenicus
On Heresies", Tertullian "On Prescription against Heretics," St. Vincent of lAnns, in his "Commoni- torv'", to insist on unity with the Catholic Church, and, for the purpose of confuting the heretical errors of private interpretation, to appeal to an authorita- tive rule of faith. In like manner, the ri.se of heret- ical sects in the three ci^nturics preceding the Ref- ormation led to an accentuation of the fundamental principles of Catholicism, notably in Moneta's "Sum- ma contra Calliaros et Waldenses" (about 122.5), and Toniuemada's "Summa de Eeclesi.l" (14.50). So to a f.ar greater extent, in the outpouring from many sources of Protestant idejis, it became the duty of the hour to defend the true nature of the Church of Christ, to vindicate its authority, its divinely au- thorized hierarchy under the primacy of the Pope, its visibility, unity, peqietuity, and infallibility, along with other doctrines and practices branded as super- stitions.
In the first heat of tliis gigantic controversy the writings on both sides were .sharply polemic, abound- ing in personal recriminations, jiut towards the close of the century there developed a tendency to treat the controverted (|uestions more in the manner of a calm, systematic apology. Two worlcs belong- ing to this time are esi>ecially noteworthy. One is the " Disputationcs do controversiis Christiana; Ki- dei" (1.5S1-92), by Robert liellannin, a monumental work of vast erudition, rich in apologetic material. The other is the " Principiorum I'idei Doctrinaliuni Demonstratio" (1.579), by Robert Stapleton, whom Dollinger pronounced to Le the prince of controver- sialists. Though not so erudite, it is more profound than the work of Hcllarrain. Another excellent work of this period is that of Martin Becan, "De Ecclesia Christi" (1633).
FouiiTH Period. CiiuiSTiArnTY m contlict with Rationalism. — (a) From the Middle of the Sevcn~ tivnth to the Xinrteenth Century. Rationalism — the setting up of the human reason as the source anil measure of all knowable truth — is, of course, not confined to any one period of human history. It h:us existed from the earliest days of philosophy. But in Christian society it did not become a notable factor till the middle of the seventeenth century, when it asserted itself chiefly in the form of Deism. It was a.ssociated, and even to a large extent iden- tified with the rapidly growing movement towards greater intellectual freedom which, stinnilated by fruitful scientific inquiry, found itself seriously ham- Iiered by the narrow views of inspiration and of his- toric Hilile-interpretation which then prevailed. The Bible had been set up as an infallible source of knowl- edge not only in matters of religion, but of history, chronology, and physical science. The result was a reaction again.st the very essentials of Christianity. Deism Ijecame the intellectual fashion of the day, leading in many cases to downright atheism. Start- ing with the principle that no religious doctrine is of value that cannot be proved by experience or by philosophical reflection, the Deists admitte<l the ex- istence of a God external to the world, but denied