"The Book of Kings can be divided into two parts, one of which is all heroic and legendary, while the other is historical, wandering around the exploits of Iskender or Alexander the Great in the East and telling with many fairy tales the story of the Sassanids until the 651 of the V The first part begins with the first man and first king, Gayumers, and has as its main subject a centuries-old war of the Iranians with the Turani, peoples of North Asia, and with the Devi or demons, creatures of Ahrimane, that is, of the genius of evil. There is no doubt that under this name of Devi there is not a very ancient population that the Iranians found in the long run when they descended into Iran, and that they had to subdue and exterminate in part. But this war against the Devi and against the Turani in the eyes of the Iranians had a truly great meaning. It visibly represented on earth the great struggle between evil and good, between the creator, Ormuzd, and the enemy of all good, Ahrimane, in which all men, for a moral duty, are obliged to take part. As evil one can and must fight with pious and good works, so it can also fight with weapons, and the heroes of Iran, when they take the field against Devi and Turani, they do nothing but satisfy this moral obligation."