Phaedo.
I am convinced, then,
said he, that
in the first place, if the earth is round and in the middle of the heavens, it
needs neither the air
nor any other similar force to keep it from falling, but its
own equipoise and the homogeneous nature of the heavens on all sides suffice to
hold it in place; for a body which is in equipoise and is placed in the center
of something which is homogeneous cannot change its inclination in any
direction, but will remain always in the same position. This, then, is the first
thing of which I am convinced.
And
rightly,
said Simmias.Secondly,
said he, I believe that the earth is very large
and that we who dwell between the pillars of Hercules
and the river Phasis live in a small part of it about the sea, like ants or
frogs about a pond, and that many other people live in many other such regions.
For I believe there are in all directions on the earth many hollows of very
various forms and sizes, into which the water and mist and air have run
together; but the earth itself is pure and is situated in the pure heaven in
which the stars are, the heaven which
those
who discourse about such matters call the ether; the water, mist and air are the
sediment of this and flow together into the hollows of the earth. Now we do not
perceive that we live in the hollows, but think we live on the upper surface of
the earth, just as if someone who lives in the depth of the ocean should think
he lived on the surface of the sea, and, seeing the sun and the stars through
the water, should think the sea was the sky, and should, by reason of
sluggishness or
feebleness, never have
reached the surface of the sea, and should never have seen, by rising and
lifting his head out of the sea into our upper world, and should never have
heard from anyone who had seen, how much purer and fairer it is than the world
he lived in. I believe this is just the case with us; for we dwell in a hollow
of the earth and think we dwell on its upper surface; and the air we call the
heaven, and think that is the heaven in which the stars move. But the fact is
the same,
that by reason of feebleness and
sluggishness, we are unable to attain to the upper surface of the air; for if
anyone should come to the top of the air or should get wings and fly up, he
could lift his head above it and see, as fishes lift their heads out of the
water and see the things in our world, so he would see things in that upper
world; and, if his nature were strong enough to bear the sight, he would
recognize that that is the real heaven
and the real light and the real earth.