And these
things cannot be adequately explained without also explaining the
affections which are concerned with sensation, nor the latter
without the former: and yet to explain them together is hardly
possible; for which reason we must assume first one or the other
and afterwards examine the nature of our hypothesis. In order,
then, that the affections may follow regularly after the
elements, let us presuppose the existence of body and soul.
First, let us enquire what we mean by saying that fire is hot;
and about this we may reason from the dividing or cutting power
which it exercises on our bodies. We all of us feel that fire is
sharp; and we may further consider the fineness of the sides, and
the sharpness of the angles, and the smallness of the particles,
and the swiftness of the motion-all this makes the action of fire
violent and sharp, so that it cuts whatever it meets. And we must
not forget that the original figure of fire [i.e. the pyramid],
more than any other form, has a dividing power which cuts our
bodies into small pieces (Kepmatizei), and thus naturally
produces that affection which we call heat; and hence the origin
of the name (thepmos, Kepma). Now, the opposite of this is
sufficiently manifest; nevertheless we will not fail to describe
it. For the larger particles of moisture which surround the body,
entering in and driving out the lesser, but not being able to
take their places, compress the moist principle in us; and this
from being unequal and disturbed, is forced by them into a state
of rest, which is due to equability and compression. But things
which are contracted contrary to nature are by nature at war, and
force themselves apart; and to this war and convulsion the name
of shivering and trembling is given; and the whole affection and
the cause of the affection are both termed cold. That is called
hard to which our flesh yields, and soft which yields to our
flesh; and things are also termed hard and soft relatively to one
another. That which yields has a small base; but that which rests
on quadrangular bases is firmly posed and belongs to the class
which offers the greatest resistance; so too does that which is
the most compact and therefore most repellent. The nature of the
light and the heavy will be best understood when examined in
connexion with our notions of above and below; for it is quite a
mistake to suppose that the universe is parted into two regions,
separate from and opposite to each other, the one a lower to
which all things tend which have any bulk, and an upper to which
things only ascend against their will. For as the universe is in
the form of a sphere, all the extremities, being equidistant from
the centre, are equally extremities, and the centre, which is
equidistant from them, is equally to be regarded as the opposite
of them all. Such being the nature of the world, when a person
says that any of these points is above or below, may he not be
justly charged with using an improper expression? For the centre
of the world cannot be rightly called either above or below, but
is the centre and nothing else; and the circumference is not the
centre, and has in no one part of itself a different relation to
the centre from what it has in any of the opposite parts. Indeed,
when it is in every direction similar, how can one rightly give
to it names which imply opposition? For if there were any solid
body in equipoise at the centre of the universe, there would be
nothing to draw it to this extreme rather than to that, for they
are all perfectly similar; and if a person were to go round the
world in a circle, he would often, when standing at the antipodes
of his former position, speak of the same point as above and
below; for, as I was saying just now, to speak of the whole which
is in the form of a globe as having one part above and another
below is not like a sensible man.
The reason why these names are used, and the circumstances
under which they are ordinarily applied by us to the division of
the heavens, may be elucidated by the following supposition:-if a
person were to stand in that part of the universe which is the
appointed place of fire, and where there is the great mass of
fire to which fiery bodies gather-if, I say, he were to ascend
thither, and, having the power to do this, were to abstract
particles of fire and put them in scales and weigh them, and
then, raising the balance, were to draw the fire by force towards
the uncongenial element of the air, it would be very evident that
he could compel the smaller mass more readily than the larger;
for when two things are simultaneously raised by one and the same
power, the smaller body must necessarily yield to the superior
power with less reluctance than the larger; and the larger body
is called heavy and said to tend downwards, and the smaller body
is called light and said to tend upwards. And we may detect
ourselves who are upon the earth doing precisely the same thing.
For we of separate earthy natures, and sometimes earth itself,
and draw them into the uncongenial element of air by force and
contrary to nature, both clinging to their kindred elements. But
that which is smaller yields to the impulse given by us towards
the dissimilar element more easily than the larger; and so we
call the former light, and the place towards which it is impelled
we call above, and the contrary state and place we call heavy and
below respectively.
