Corresponding to these ideas we have: (I). The Agnostic reaction as manifested in the Poet ‘Umar Ḵẖayyām (12{th} century) who cried out in his intellectual despair:-- The joyous souls who quaff potations deep, And saints who in the mosque sad vigils keep, Are lost at sea alike, and find no shore, One only wakes, all others are asleep. (II). The monotheistic reaction of Ibn Taimiyya and his followers in the 13{th} century. (III). The Pluralistic reaction of Wāḥid Maḥmūd[119:1] in the 13{th} century. [119:1] Dabistān, Chap: 8. Speaking from a purely philosophical standpoint, the last movement is most interesting. The history of Thought illustrates the operation of certain general laws of progress which are true of the intellectual annals of different peoples. The German systems of monistic thought invoked the pluralism of Herbart; while the pantheism of Spinoza called forth the monadism of Leibniz. The operation of the same law led Wāḥid Maḥmūd to deny the truth of contemporary monism, and declare that Reality is not one but many. Long before Leibniz he taught that the Universe is a combination of what he called "Afrād"--essential units, or simple atoms which have existed from all eternity, and are endowed with life. The law of the Universe is an ascending perfection of elemental matter, continually passing from lower to higher forms determined by the kind of food which the fundamental units assimilate. Each period of his cosmogony comprises 8,000 years, and after eight such periods the world is decomposed, and the units re-combine to construct a new universe. Wāḥid Maḥmūd succeeded in founding a sect which was cruelly persecuted, and finally stamped out of existence by S̱ẖāh ‘Abbās. It is said that the poet Ḥāfiz of S̱ẖīrāz believed in the tenets of this sect. C. _Reality as Light or Thought._ The third great school of Ṣūfīism conceives Reality as essentially Light or Thought, the very nature of which demands something to be thought or illuminated. While the preceding school abandoned Neo-Platonism, this school transformed it into new systems. There are, however, two aspects of the metaphysics of this school. The one is genuinely Persian in spirit, the other is chiefly influenced by Christian modes of thought. Both agree in holding that the fact of empirical diversity necessitates a principle of difference in the nature of the ultimate Reality. I now proceed to consider them in their historical order. I. Reality as Light--Al-Is̱ẖrāqī. Return to Persian Dualism.