TIMAEU [38]
just off the stocks; they are locked firmly together and yet the whole
mass is soft and delicate, being freshly formed of marrow and nurtured
on milk. Now when the triangles out of which meats and drinks are
composed come in from without, and are comprehended in the body, being
older and weaker than the triangles already there, the frame of the
body gets the better of them and its newer triangles cut them up,
and so the animal grows great, being nourished by a multitude of
similar particles. But when the roots of the triangles are loosened by
having undergone many conflicts with many things in the course of
time, they are no longer able to cut or assimilate the food which
enters, but are themselves easily divided by the bodies which come
in from without. In this way every animal is overcome and decays,
and this affection is called old age. And at last, when the bonds by
which the triangles of the marrow are united no longer hold, and are
parted by the strain of existence, they in turn loosen the bonds of
the soul, and she, obtaining a natural release, flies away with joy.
For that which takes place according to nature is pleasant, but that
which is contrary to nature is painful. And thus death, if caused by
disease or produced by wounds, is painful and violent; but that sort
of death which comes with old age and fulfils the debt of nature is
the easiest of deaths, and is accompanied with pleasure rather than
with pain.
Now every one can see whence diseases arise. There are four
natures out of which the body is compacted, earth and fire and water
and air, and the unnatural excess or defect of these, or the change of
any of them from its own natural place into another, or-since there
are more kinds than one of fire and of the other elements-the
assumption by any of these of a wrong kind, or any similar
irregularity, produces disorders and diseases; for when any of them is
produced or changed in a manner contrary to nature, the parts which
were previously cool grow warm, and those which were dry become moist,
and the light become heavy, and the heavy light; all sorts of
changes occur. For, as we affirm, a thing can only remain the same
with itself, whole and sound, when the same is added to it, or
subtracted from it, in the same respect and in the same manner and
in due proportion; and whatever comes or goes away in violation of
these laws causes all manner of changes and infinite diseases and
corruptions. Now there is a second class of structures which are
also natural, and this affords a second opportunity of observing
diseases to him who would understand them. For whereas marrow and bone
and flesh and sinews are composed of the four elements, and the blood,
though after another manner, is likewise formed out of them, most
diseases originate in the way which I have described; but the worst of
all owe their severity to the fact that the generation of these
substances stances in a wrong order; they are then destroyed. For
the natural order is that the flesh and sinews should be made of
blood, the sinews out of the fibres to which they are akin, and the
flesh out of the dots which are formed when the fibres are
separated. And the glutinous and rich matter which comes away from the
sinews and the flesh, not only glues the flesh to the bones, but
nourishes and imparts growth to the bone which surrounds the marrow;
and by reason of the solidity of the bones, that which filters through
consists of the purest and smoothest and oiliest sort of triangles,
dropping like dew from the bones and watering the marrow.
Now when each process takes place in this order, health commonly
results; when in the opposite order, disease. For when the flesh
becomes decomposed and sends back the wasting substance into the
veins, then an over-supply of blood of diverse kinds, mingling with
air in the veins, having variegated colours and bitter properties,
as well as acid and saline qualities, contains all sorts of bile and
serum