III. We have traced the history of Mysticism in Islam from the ascetic movement of the first century, in which it originated, to a point where it begins to pass beyond the sphere of Muḥammadan influence and to enter on a strange track, of which the Prophet assuredly never dreamed, although the Ṣúfís constantly pretend that they alone are his true followers. I do not think it can be maintained that Ṣúfiism of the theosophical and speculative type, which we have now to consider, is merely a development of the older asceticism and quietism which have been described in a former chapter. The difference between them is essential and must be attributed in part, as Von Kremer saw,[723] to the intrusion of some extraneous, non-Islamic, element. As to the nature of this new element there are several conflicting theories, which have been so clearly and fully stated by Professor Browne in his _Literary History of Persia_ (vol. i, p. 418 sqq.) that I need not dwell upon them here. Briefly it is claimed-- (_a_) That Ṣúfiism owes its inspiration to Indian philosophy, and especially to the Vedanta. (_b_) That the most characteristic ideas in Ṣúfiism are of Persian origin. (_c_) That these ideas are derived from Neo-platonism. Instead of arguing for or against any of the above theories, all of which, in my opinion, contain a measure of truth, I propose in the following pages to sketch the historical evolution of the Ṣúfí doctrine as far as the materials at my disposal will permit. This, it seems to me, is the only possible method by which we may hope to arrive at a definite conclusion as to its origin. Since mysticism in all ages and countries is fundamentally the same, however it may be modified by its peculiar environment, and by the positive religion to which it clings for support, we find remote and unrelated systems showing an extraordinarily close likeness and even coinciding in many features of verbal expression. Such resemblances can prove little or nothing unless they are corroborated by evidence based on historical grounds. Many writers on Ṣúfiism have disregarded this principle; hence the confusion which long prevailed. The first step in the right direction was made by Adalbert Merx,[724] who derived valuable results from a chronological examination of the sayings of the early Ṣúfís. He did not, however, carry his researches beyond Abú Sulaymán al-Dárání († 830 A.D.), and confined his attention almost entirely to the doctrine, which, according to my view, should be studied in connection with the lives, character, and nationality of the men who taught it.[725] No doubt the origin and growth of mysticism in Islam, as in all other religions, _ultimately_ depended on general causes and conditions, not on external circumstances. For example, the political anarchy of the Umayyad period, the sceptical tendencies of the early ‘Abbásid age, and particularly the dry formalism of Moslem theology could not fail to