to figurative language for further illustration, comparing the form of the good to the
sun which gives visibility to the objects of the sensible world and the power of seeing
to the eye. So the good makes the objects of thought (the forms) intelligible and gives
the power of knowledge to the mind (Republic, 506d–509c). Plato then explores
the distinction between the visible and intelligible worlds with the analogy of the
divided line, through which he clarifies four sharply distinct mental states (the figure
clarifies since in life they might not be so independent of one another). Opinion can
be informed and true, or illusory and false; knowledge may be of ultimate reality (the
forms), or of a lesser reality, which nevertheless transcends the world of sense
(mathematical propositions).
Then comes the allegory of the cave. The prisoners in the cave have been
fettered since childhood in their underground cave and can only look in front of them.
They have one fixed view, from which they can see reflected on the wall opposite
shadows of objects being carried through the cave by men walking on a road above
them, in front of which a wall has been built. Above and behind the road is a fire,
whose light casts the shadows of the objects, which may be figures of men or animals
in stone. For the prisoners, the shadows are the only realities. If one of them is let
loose and compelled to turn his head and walk towards the fire, faced with the passing
objects, he will resist the new reality, taking refuge in the familiar. The light of the fire
will hurt his eyes. If he is forced to make the ascent to daylight, the process will be
painful and he will at first not be able to see what is pointed out to him as real. Until
his eyes grow accustomed to the light, he will look at shadows and reflections, then
at objects themselves, then at the heavens by night. The last thing he will be able to
look at will be the sun itself. Then he will come to realise that the sun is the cause of
all things. Reflecting upon his former life, he will see that it was worthless. If he is
made to come back to the cave, he will again be blinded and make a fool of himself
in the eyes of his former fellows, who will think the ascent has destroyed his eyesight
and is not worth making. If anyone attempts to release them they will try to kill him.
Socrates likens the ascent into the upper world to the progress of the mind into
the intelligible realm. The final perception is of the form of the good, which is the
cause of all things right and true (Republic, 517b–517c).
In passing, it may be noted that another aspect of this ascent is the ascent of the
ideal lover on the ladder of beauty, from the beautiful objects of the physical world
on the lower rung, to the beauty of the soul and on to the beauty of abstractions, like
laws and institutions, until he finally ascends to contemplation of the form of beauty
itself, an incommunicable mystical experience that is the climax of the prophetess
Diotima’s speech to Socrates on the nature of eros in the Symposium(210–212).
Ordinary earthly life is lived in a benighted condition of ignorance from a fixed
point of view, in which the deluded soul is imprisoned, without knowing it, in a world
of transient shadows. The impeding fetters are not simply intellectual, but are also
198 THE GREEKS