2. The Muslim conquerors found the Christian church split up into three main divisions,—to say nothing of many sects. The Monophysite church, alongside of the Orthodox State-church, preponderated in Syria proper, and the Nestorian church in Persia. The difference between the doctrinal systems of these churches was perhaps not without importance for the development of Muslim Dogmatics. According to the teaching of the Monophysites, God and Man were united in one nature in Christ, whereas the Orthodox, and in a still more pronounced manner the Nestorians, discriminated between a Divine nature and a human nature in him. Now nature means, above everything, energy or operative principle. The question, accordingly, which is at issue, is whether the Divine, and the human Willing and Acting are one and the same in Christ or different. The Monophysites, from speculative and religious motives, gave prominence to the Unity in Christ their God, at the expense of the human element: The Nestorians, on the other hand, emphasized, in contrast with the Divine element, all that is specially characteristic of human Being, Willing and Acting. The latter view, however, favoured by political circumstances and conditions of culture, offers freer play to philosophical speculations on the world and on life. In point of fact the Nestorians did most for the cultivation of Greek Science. 3. Syriac was the language both of the Western and of the Eastern or Persian Church; but Greek was also taught along with it in the Cloister schools. Rasain and Kinnesrin must be mentioned as being centres of culture in the Western or Monophysite Church. Of more importance, at the outset at least, was the school of Edessa, inasmuch as the dialect of Edessa had risen to the position of the literary language; but in the year 489 the school there was closed because of the Nestorian views held by its teachers. It was then re-opened in Nisibis, and, being patronized by the Sasanids on political grounds, it disseminated Nestorian belief and Greek knowledge throughout Persia.