Like the kindred tribes in India, the Arians in Iran were not destitute of imagination and a tendency to abstraction. But from the first these qualities were restrained within narrower limits owing to the nature of the land,--while the scenery and phenomena of the Ganges tended to develop them,--and the teaching of Zarathrustra provided a counterpoise in the practical requirements which it set up. Labour took the place of idle dreaming, conflict and energetic activity the place of asceticism, and the imagination received impulses to simple and great conceptions. The ethics of this religion guaranteed the conditions of a healthy human existence; man's effort was essentially directed to this present world, and the duties imposed upon him were such as he could fulfil. Thus they led to results different from the introspection, quietism, and asceticism of the Indians, and the relapse into sensuality which was the inseparable concomitant of the latter. The doctrine of Zarathrustra contributed essentially to educate the tribes which followed it in truthfulness and manliness, and to qualify them for energy and action. In their sensible, intelligent view of the world, in putting theory below practice, and aiming at an active life, the Iranians are as far before the Indians as the Romans are before the Greeks. If Eastern Iran, in the first instance, discharged a religious mission, the duty of politics was undertaken by the West. The empire of the Medes and of the Persians rose and fell, but the religion of Auramazda survived the fall of the Achæmenids. It rose to renewed life with the empire of the Arsacids and Sassanids. The national reaction against the dominion of the Seleucids began with the Parthians; the empire of the Sassanids, which subsequently took the place of that of the Arsacids, was supported in the first place by the tribes of the Persians, and was connected with the remembrance of the Achæmenids. Yet from the first the Sassanids were prepared to deal equal measure to the East and West of Iran; in opposition to any attempt at religious innovation they held firmly to the tradition of the East. When after a rule of more than four centuries the Sassanids succumbed to the invasion of the Arabs, Yezdegerd III. attempted to maintain himself in Merv, as Darius III. had attempted to maintain himself in Bactria. The attempt failed. Iran succumbed to Islam. Yet it was the East from which, not quite two centuries after the fall of the Sassanids, a reaction commenced against the Arabs, and this gradually increased till it rescued the nationality and the language of Iran. It was the viceroys in the districts of the East who rebelled against the Chalifate, and they found support in the population of their provinces. A process similar to that which had previously broken down the dominion of the Seleucids over Iran shattered the empire of the Abbasids. The impulse to this movement rose in