Zarathrustra had increased the means for keeping off the evil ones, and had made the struggle against the wicked spirits easier for men. But the time will come when the struggle will be no longer necessary, and the bright spirits alone will rule. This doctrine is indicated even in the Gathas.[303] In the book of the law Zarathrustra says to Angromainyu: he will smite the Daevas till Çaoshyant is born from the water of Kançava in the eastern region.[304] Çaoshyant, _i.e._ the useful, the saviour, is called in the Avesta, "the sublime, the victorious;" he will smite the Druj, and Aeshma will bow before him. He will make the world to live for ever, without age and death; the dead will rise again, and the living will be immortal. Vohumano will smite Akomano, Asha will kill the lies. Haurvatat and Ameretat will destroy thirst and hunger: "The evil-doer Angromainyu, robbed of his dominion, bows himself."[305] This doctrine of the Avesta also was well known to the western world. In Herodotus Prexaspes tells Cambyses that when the dead rise again he will see Smerdis and Astyages.[306] Theopompus of Chios tells us: Zoroaster had proclaimed that there would be a time in which the dead will arise, and men will be immortal, and everything will be done by their invocations. Last of all, Hades will pass away; men will then be happy; they will need no nourishment, and throw no shadows, and the god who will accomplish this rests for a time, but not a long time for a god.[307] It is true that men required no nourishment when Çaoshyant had appeared, in the meaning of the Avesta, for Haurvatat and Ameretat had overcome hunger and thirst as well as sickness and death; and as the dark side of man was taken away, and only the bright side remained, they could not cast any shadows.