Al-Ghazali completes the development of orthodox Muslim theology. From this time forth it ceased to have any originality, and for the most part showed signs of decadence. Here and there we find Sufi revivals; indeed, Sufism is the only phase of Islam which kept free from the rigid conservatism which has laid its iron hand of repression upon Muslim life and thought generally. In Yemen the system of al-Ghazali was kept alive by generations of Sufis, but for the most part Sufism preferred less orthodox paths. Against these Sufi movements we see from time to time others of a distinctly reactionary character, such as that of the Wahabis, who opposed the theology of al-Ghazali when it was generally recognised as the orthodox teaching at Mecca, and in this they were followed by the Sanusi. _Sayyid Murtada_ (d. 1205 A.H. = 1788 A.D.), a native of Zabid in Yihama, wrote a commentary on al-Ghazali’s _Ihya `Ulum ad-Din_, and thus revived the study of the great scholastic theologian. From that time the Islamic community has not lacked neo-Ghazalian students, and many consider that that school contains the best promise for modern Islam. CHAPTER IX WESTERN PHILOSOPHY Muslim rule in North Africa west of the Nile valley was commenced under conditions very different from those prevailing in Egypt and Syria. The Arabs found this land occupied by the Berbers or Libyans, the same race which from the time of the earliest Pharaohs had been a perpetual menace to Egypt, and which, on the Mediterranean seaboard, had offered a serious problem to Phœnician, Greek, Roman and Gothic colonists. For some thousands of years these Berbers had remained very much the same as when they had emerged from the neolithic stage, and were hardy desert men like the Arabs in pre-Islamic times. Their language was not Semitic, but shows very marked Semitic affinities, and, although language transmission is often quite distinct from racial descent, it seems probable that in this case there was a parallel, and this is best explained by supposing that both were derived from the neolithic race which at one time spread along the whole of the south coast of the Mediterranean and across into Arabia, but that some cause, perhaps the early development of civilization in the Nile valley, had cut off the eastern wing from the rest, and this segregated portion developed the peculiar characteristics which we describe as Semitic. The series of Greek, Punic, Roman, and Gothic settlements had left no permanent mark on the Berber population, on their language, or on their culture. At the time of the Arab invasion the country was theoretically under the Byzantine Empire, and the invading Arabs had to meet the resistance of a Greek army; but this was not a very serious obstacle, and the invaders were soon left face to face with the Berber tribes.