GENIUS, a good or evil spirit or dæmon, whom the ancients supposed set over each person, to direct his birth, accompany him in life, and to be his guard. See DÆMON.
Among the Romans, Festus observes, the name genius was given to the god who had the power of doing all things, deum qui vim obtineret rerum omnium gerendarum; which Vossius, de Idol. rather chooses to read genendarum, who has the power of producing all things; by reason Censorinus frequently uses gerere for gignere.
Accordingly St Augustin, de Civitate Dei, relates, from Varro, that the Genius was a god who had the power of generating all things; and presided over them when produced.
Festus adds, that Aufustius spake of the genius as the Son of God, and the Father of men, who gave them life; others, however, represented the genius as the peculiar or tutelary god of each place; and it is certain, the last is the most usual meaning of the word. The ancients had their genii of nations, of cities, of provinces, &c. Nothing is more common than the following inscription on medals, GENIUS POPULI ROM. "the genius of the Roman people;" or GENIO POP. ROM. "to the genius of the Roman people. In this sense genius and lar were the same thing; as, in effect, Censorinus and Apulius affirm they were. See LARES and PENATES.
The Platonists, and other eastern philosophers, supposed the genii to inhabit the vast region or extent of air between earth and heaven. They were a sort of intermediate powers, who did the office of mediators between gods and men. They were the interpreters and agents of the gods; communicated the wills of the deities to men; and the prayers and vows of men to the gods. As it was unbecoming the majesty of the gods to enter into such trifling concerns, this became the lot of the genii, whose nature was a mean between the two; who derived immortality from the one, and passions from the other; and who had a body framed of an aerial matter. Most of the philosophers, however, held, that the genii of particular men were born with them, and died; and Plutarch attributes the ceasing of oracles partly to the death of the genii.—See ORACLE.
The heathens, who considered the genii as the guardians of particular persons, believed that they rejoiced and were afflicted at all the good and ill fortune that befell their wards. They never, or very rarely, appeared to them; and then only in favour of some person of extraordinary virtue or dignity. They likewise held a great difference between the genii of different men; and that some were much more powerful than others: on which principle it was, that a wizard in Appian bids Antony keep at a distance from Octavius, by reason Antony's genius was inferior to and stood in awe of that of Octavius. There were also evil genii, who took a pleasure in persecuting men, and bringing them evil tidings: such was that mentioned by Plutarch which appeared to Brutus the night before the battle of Philippi. These were also called larvæ and lemures. See LARVÆ and LEMURES.