letting out of the breath; for death occurs when the compression by

the surrounding air gains the upper hand, and, the animal being unable

to respire, the air from outside can no longer enter and counteract

the compression. Death is the departure of those forms owing to the

expulsive pressure exerted by the surrounding air. Death, however,

occurs not by haphazard but, when natural, owing to old age, and, when

unnatural, to violence.

But the reason for this and why all must die Democritus has by no

means made clear. And yet, since evidently death occurs at one time of

life and not at another, he should have said whether the cause is

external or internal. Neither does he assign the cause of the

beginning of respiration, nor say whether it is internal or

external. Indeed, it is not the case that the external mind

superintends the reinforcement; rather the origin of breathing and

of the respiratory motion must be within: it is not due to pressure

from around. It is absurd also that what surrounds should compress and

at the same time by entering dilate. This then is practically his

theory, and how he puts it.

But if we must consider that our previous account is true, and

that respiration does not occur in every animal, we must deem that

this explains death not universally, but only in respiring animals.

Yet neither is it a good account of these even, as may clearly be seen

from the facts and phenomena of which we all have experience. For in

hot weather we grow warmer, and, having more need of respiration, we

always breathe faster. But, when the air around is cold and

contracts and solidifies the body, retardation of the breathing

results. Yet this was just the time when the external air should enter

and annul the expulsive movement, whereas it is the opposite that

occurs. For when the breath is not let out and the heat accumulates

too much then we need to respire, and to respire we must draw in the

breath. When hot, people breathe rapidly, because they must do so in

order to cool themselves, just when the theory of Democritus would