The emperor’s fears and suspicions were immensely aggravated by the adepts in the dark arts of the East. The astrologers were a great and baneful power in the early Empire. They inspired illicit ambitions, or they stimulated them, and they often suggested to a timorous prince the danger of conspiracy. These venal impostors, in the words of Tacitus, were always being banished, but they always returned. For the men who drove them into temporary exile had the firmest faith in their skill. The prince would have liked to keep a monopoly of it, while he withdrew from his nobles the temptation which might be offered to their ambition by the mercenary adept.(259) Dion Cassius and Suetonius, who were themselves eager believers in this superstition, never fail to record the influence of the diviners. The reign of Tiberius is full of dark tales about them.(260) Claudius drove Scribonianus into exile for consulting an astrologer about the term of his reign.(261) On the appearance of a flaming comet, Nero was warned by his diviner, Bilbilus, that a portent, which always boded ill to kings, might be expiated by the blood of their nobles.(262) Otho’s astrologer, Seleucus, who had promised that he should survive Nero,(263) stimulated his ambition to be the successor of Galba. Vitellius, as superstitious as Nero or Otho, cruelly persecuted the soothsayers and ordered their expulsion from Italy.(264) He was defied by a mocking edict of the tribe, ordaining his own departure from earth by a certain day.(265) Vespasian once more banished the diviners from Rome, but, obedient to the superstition which cradled the power of his dynasty, he retained the most skilful for his own guidance.(266) The terror of Domitian’s last days was heightened by a horoscope, which long before had foretold the time and manner of his end.(267) Holding such a faith as this, it is little wonder that the emperors should dread its effect on rivals who were equally credulous, or that superstition, working on ambitious hopes, should have been the nurse of treason. Thus the emperor’s uncertain position made him ready to suspect and anticipate a treachery which may often have had no existence. The objects of his fears in their turn were driven into conspiracy, sometimes in self-defence, sometimes from the wish to seize a prize which seemed not beyond their grasp. Gossip, lampoon, and epigram redoubled suspicion, while they retaliated offences. And cruel repression either increased the danger of revolt in the more daring, or the degradation of the more timorous.