Question III
In the Republic (Book VI; 509D-511E), he supposed the universe, as one line, to be cut into two unequal sections; again he cuts each of these sections in two after the same proportion, and supposes the two sections first made to constitute the two genera of things sensible and things intelligible in the universe. The first represents the genus of intelligibles, comprehending in the first subdivision of the primitive forms or ideas, in the second the mathematics. Of sensibles, the first subdivision comprehends solid bodies, the second comprehends the images and representations of them. Moreover, to every one of these four he has assigned its proper judicatory faculty: -- to the first, reason; to the mathematics, the understanding; to the sensibles, belief; to images and likenesses, conjecture.
But What Does He Mean By Dividing The Universe Into Unequal Parts? And Which Of The Sections, The Intelligible Or The Sensible, Is the Greater? For In This He Has Not Explained Himself.
1. At first sight it will appear that the sensible is the greater
portion. For the essence of intelligibles being indivisible, and in the same respect ever
the same, is contracted into a little, and pure; but an essence divisible and pervading
bodies constitutes the sensible part. Now what is immaterial is limited; but body in
respect of matter is infinite and unlimited, and it becomes sensible only when it is
defined by partaking of the intelligible. Besides, as every sensible has many images,
shadows, and representations, and from one and the same original several copies may be
taken both by nature and art; so the latter must needs exceed the former in number,
according to Plato, who makes things intelligible to be patterns or ideas of things
sensible, like the originals of images and reflections. Further, Plato derives the
knowledge of ideas from body by abstraction and cutting away, leading us by various steps
in mathematical discipline from arithmetic to geometry, thence to astronomy, and setting
harmony above them all. For things become geometrical by the accession of profundity to
magnitude; astronomical, by the accession of motion to solidity; harmonical, by the
accession of sound to motion. Abstract then sound from moving bodies, motion from solids,
profundity from superficies, magnitude from quantity, we are then come to pure
intelligible ideas, which have no distinction among themselves in respect of the one
single intelligible essence. For unity makes no number, unless joined by the infinite
binary; then it makes a number. And thence we proceed to points, thence to lines, and from
them to superficies, and profundities, and bodies, and to the qualities of bodies so and
so qualified. Now the reason is the only judicatory faculty of intelligibles; and the
understanding is the reason in the mathematics, where intelligibles appear as a reflection
in mirrors. But as to the knowledge of bodies, because of their multitude, Nature has
given us five powers or distinctions of senses; nor are all bodies discerned by them, many
escaping sense by reason of their smallness. And though every one of us consists of a body
and soul, yet the hegemonic and intellectual faculty is small, being hid in the huge mass
of flesh. And the case is the same in the universe, as to sensible and intelligible. For
intleligibles are the principle of bodily things, but every thing is greater than the
principles whence it came.
2. Yet, on the contrary, some will say that, by comparing sensibles
with intelligibles, we match things mortal with divine, in some measure; for God is in
intelligibles. Besides, the thing contained is ever less than the containing, and the
nature of the universe contains the sensible in the intelligible. For God, having placed
the soul in the middle, hath extended it through all, and hath covered it all round with
bodies. The soul is invisible, and cannot be perceived by any of the senses, as Plato says
in his Book of Laws; therefore every man must die, but the world shall never die. For
mortality and dissolution surround every one of our vital faculties. The case is quite
otherwise in the world; for the corporeal part, contained in the middle by the more noble
and unalterable principles, is ever preserved. And a body is said to be without parts and
indivisible for its minuteness; but what is incorporeal and intelligible is so, as being
simple and sincere, and void of all firmness and difference. Besides, it were folly to
think to judge of incorporeal things by corporeal. The present, or now, is said to
be without parts and indivisible, since it is everywhere and no part of the world is void
of it. But all affections and actions, and all corruptions and generations in the world,
are contained by this now. But the mind is judge only of what is intelligible, as
the sight is of light, by reason of its simplicity and similitude. But bodies, having
several differences and diversities, are comprehended, some by one judicatory faculty,
others by another, as by several organs. Yet they do not well who despise the intelligible
and intelligent faculty in us; for being great, it comprehend all senses, and attains to
things divine. The most important thing he himself teaches in his Banquet, where he shows
us how we should use amatorious matters, turning our minds from sensible goods to thing
discernible only by the reason, that we ought not to be enslaved by the beauty of any
body, study, or learning, but laying aside such pusillanimity, should turn to the vast
ocean of beauty (Symposium 210D).