TIMAEU [27]
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. Now the relations of these must necessarily vary,
because the principal masses of the different elements hold opposite
positions; for that which is light, heavy, below or above in one place
will be found to be and become contrary and transverse and every way
diverse in relation to that which is light, heavy, below or above in
an opposite place. And about all of them this has to be
considered:-that the tendency of each towards its kindred element
makes the body which is moved heavy, and the place towards which the
motion tends below, but things which have an opposite tendency we call
by an opposite name. Such are the causes which we assign to these
phenomena. As to the smooth and the rough, any one who sees them can
explain the reason of them to another. For roughness is hardness
mingled with irregularity, and smoothness is produced by the joint
effect of uniformity and density.
The most important of the affections which concern the whole body
remains to be considered-that is, the cause of pleasure and pain in
the perceptions of which I have been speaking, and in all other things
which are perceived by sense through the parts of the body, and have
both pains and pleasures attendant on them. Let us imagine the
causes of every affection, whether of sense or not, to be of the
following nature, remembering that we have already distinguished
between the nature which is easy and which is hard to move; for this
is the direction in which we must hunt the prey which we mean to take.
A body which is of a nature to be easily moved, on receiving an
impression however slight, spreads abroad the motion in a circle,
the parts communicating with each other, until at last, reaching the
principle of mind, they announce the quality of the agent. But a
body of the opposite kind, being immobile, and not extending to the
surrounding region, merely receives the impression, and does not
stir any of the neighbouring parts; and since the parts do not
distribute the original impression to other parts, it has no effect of
motion on the whole animal, and therefore produces no effect on the
patient. This is true of the bones and hair and other more earthy
parts of the human body; whereas what was said above relates mainly to
sight and hearing, because they have in them the greatest amount of
fire and air. Now we must conceive of pleasure and pain in this way.
An impression produced in us contrary to nature and violent, if
sudden, is painful; and, again, the sudden return to nature is
pleasant; but a gentle and gradual return is imperceptible and vice
versa. On the other hand the impression of sense which is most
easily produced is most readily felt, but is not accompanied by
Pleasure or pain; such, for example, are the affections of the
sight, which, as we said above, is a body naturally
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. Now the relations of these must necessarily vary,
because the principal masses of the different elements hold opposite
positions; for that which is light, heavy, below or above in one place
will be found to be and become contrary and transverse and every way
diverse in relation to that which is light, heavy, below or above in
an opposite place. And about all of them this has to be
considered:-that the tendency of each towards its kindred element
makes the body which is moved heavy, and the place towards which the
motion tends below, but things which have an opposite tendency we call
by an opposite name. Such are the causes which we assign to these
phenomena. As to the smooth and the rough, any one who sees them can
explain the reason of them to another. For roughness is hardness
mingled with irregularity, and smoothness is produced by the joint
effect of uniformity and density.
The most important of the affections which concern the whole body
remains to be considered-that is, the cause of pleasure and pain in
the perceptions of which I have been speaking, and in all other things
which are perceived by sense through the parts of the body, and have
both pains and pleasures attendant on them. Let us imagine the
causes of every affection, whether of sense or not, to be of the
following nature, remembering that we have already distinguished
between the nature which is easy and which is hard to move; for this
is the direction in which we must hunt the prey which we mean to take.
A body which is of a nature to be easily moved, on receiving an
impression however slight, spreads abroad the motion in a circle,
the parts communicating with each other, until at last, reaching the
principle of mind, they announce the quality of the agent. But a
body of the opposite kind, being immobile, and not extending to the
surrounding region, merely receives the impression, and does not
stir any of the neighbouring parts; and since the parts do not
distribute the original impression to other parts, it has no effect of
motion on the whole animal, and therefore produces no effect on the
patient. This is true of the bones and hair and other more earthy
parts of the human body; whereas what was said above relates mainly to
sight and hearing, because they have in them the greatest amount of
fire and air. Now we must conceive of pleasure and pain in this way.
An impression produced in us contrary to nature and violent, if
sudden, is painful; and, again, the sudden return to nature is
pleasant; but a gentle and gradual return is imperceptible and vice
versa. On the other hand the impression of sense which is most
easily produced is most readily felt, but is not accompanied by
Pleasure or pain; such, for example, are the affections of the
sight, which, as we said above, is a body naturally