Like many of his predecessors, Plotinus recognized a difference between the mental necessities of the educated and the vulgar, justifying mythology on the ground that it was very useful to those who were not yet emancipated from the sensible. Aristotle, in his Metaphysics, referring to mythology and the gods in human form, had remarked, "Much has been mythically added for the persuasion of the multitude, and also on account of the laws and for other useful ends." But Plotinus also held that the gods are not to be moved by prayer, and that both they and the dæmons occasionally manifest themselves visibly; that incantations may be lawfully practised, and are not repugnant to philosophy. In the body he discerns a penitential mechanism for the soul. He believes that the external world is a mere phantom--a dream--and the indications of the senses altogether deceptive. The union with the divinity of which he speaks he describes as an intoxication of the soul which, forgetting all external things, becomes lost in the contemplation of "the One." The doctrinal philosophy of Plotinus presents a trinity in accordance with the Platonic idea. (1.) The One, or Prime essence. (2.) The Reason. (3.) The Soul. Of the first he declares that it is impossible to speak fully, and in what he says on this point there are many apparent contradictions, as when he denies oneness to the one. His ideas of the trinity are essentially based on the theory of emanation. He describes how the second principle issues by emanation out of the first, and the third out of the second. The mechanism of this process may be illustrated by recalling how from the body of the sun issues forth light, and from light emerges heat. In the procession of the third from the second principle it is really Thought arising from Reason; but Thought is the Soul. The mundane soul he considers as united to nothing; but on these details he falls into much mysticism, and it is often difficult to see clearly his precise meaning, as when he says that Reason is surrounded by Eternity, but the Soul is surrounded by Time. He carries Idealism to its last extreme, and, as has been said, looks upon the visible world as a semblance only, deducing from his doctrine moral reflections to be a comfort in the trials of life. Thus he says that "sensuous life is a mere stage-play; all the misery in it is only imaginary, all grief a mere cheat of the players." "The soul is not in the game; it looks on, while nothing more than the external phantom weeps and laments." "Passive affections and misery light only on the outward shadow of man." The great end of existence is to draw the soul from external things and fasten it in contemplation on God. Such considerations teach us a contempt for virtue as well as for vice: "Once united with God, man leaves the virtues, as on entering the sanctuary he leaves the images of the gods in the ante-temple behind." Hence we should struggle to free ourselves from everything low and mean: to