the screens which conjurors put up in front of their audience, and above which they exhibit their wonders. . . . Also figure to yourself a number of persons walking behind this wall, and carrying with them statues of men and images of other animals wrought in wood and stone and all kinds of materials, together with various other articles, which overtop the wall; and, as you might expect, let some of the passers-by be talking, and others silent."—D.
"This cave," Socrates continues, "is the world, and the fire that lights it is the sun, and these poor prisoners are ourselves—
and all sights or sounds in this twilight region are but the shadows or echoes of real objects. And as sometimes a prisoner in this cave may be released from his chains, and turned round, and led up to the light of day; so may our souls pass upwards from the darkness of mere opinion, and from the shadowy impressions of sense into the pure sunlight of eternal truth, lighted by the Idea of Good—in itself the source of all truth and beauty."
But "What is the Good?" Plato tells us, truly enough, that it is what all men pursue under different names,—deriving its existence, seeking its reality, yet totally unable to explain its nature; and he compares it in a parable, as we have seen, to the sun which illuminates the eternal world of Ideas, but as to its own essential nature he leaves us still in the dark. The philosophers in his State will know it, he says, for their souls will be enlightened, but he does not
