The wise instructions of Severus never made any lasting impression on the mind of his son, who, although not destitute of imagination and eloquence, was equally devoid of judgment and humanity. One dangerous maxim, worthy of a tyrant, was remembered and abused by Caracalla. “To secure the affections of the army, and to esteem the rest of his subjects as of little moment.” But the liberality of the father had been restrained by prudence, and his indulgence to the troops was tempered by firmness and authority. The careless profusion of the son was the policy of one reign, and the inevitable ruin both of the army and of the empire. The vigor of the soldiers, instead of being confirmed by the severe discipline of camps, melted away in the luxury of cities. The excessive increase of their pay and donatives exhausted the state to enrich the military order, whose modesty in peace, and service in war, is best secured by an honorable poverty. The demeanor of Caracalla was haughty and full of pride; but with the troops he forgot even the proper dignity of his rank, encouraged their insolent familiarity, and, neglecting the essential duties of a general, affected to imitate the dress and manners of a common soldier. It was impossible that such a character, and such conduct as that of Caracalla, could inspire either love or esteem; but as long as his vices were beneficial to the armies, he was secure from the danger of rebellion. A secret conspiracy, provoked by his own jealousy, was fatal to the tyrant. The Prætorian præfecture was divided between two ministers. The military department was intrusted to Adventus, an experienced rather than able soldier; and the civil affairs were transacted by Opilius Macrinus, who, by his dexterity in business, had raised himself, with a fair character, to that high office. But his favor varied with the caprice of the emperor, and his life might depend on the slightest suspicion, or the most casual circumstance. Malice or fanaticism had suggested to an African, deeply skilled in the knowledge of futurity, a very dangerous prediction, that Macrinus and his son were destined to reign over the empire. The report was soon diffused through the province; and when the man was sent in chains to Rome, he still asserted, in the presence of the præfect of the city, the faith of his prophecy. That magistrate, who had received the most pressing instructions to inform himself of the _successors_ of Caracalla, immediately communicated the examination of the African to the Imperial court, which at that time resided in Syria. But, notwithstanding the diligence of the public messengers, a friend of Macrinus found means to apprise him of the approaching danger.