126 Hippocratic Corpus and Diocles of Carystus
categorical difference, and the cause for mental disorders is virtually always
sought in bodily factors.
Mental faculties are given a more independent role in the Hippocratic
writingOn the Sacred Disease, in which the function of the brain is char-
acterised as ‘interpreting’ (hermeneus ̄ ) what is derived from the air outside.
This is in many respects a key text, not least because of the author’s polemic
stance to rival views:
For these reasons I believe that the brain is the most powerful part in a human
being. So long as it is healthy, it is the interpreter of what comes to the body from
the air. Consciousness is provided by the air. The eyes, ears, tongue, hands and
feet carry out what the brain knows, for throughout the body there is a degree
of consciousness proportionate to the amount of air which it receives. As far as
understanding is concerned, the brain is also the part that transmits this, for when
a man draws in a breath it first arrives at the brain, and from there it is distributed
over the rest of the body, having left behind in the brain its best portion and
whatever contains consciousness and thought. For if the air went first to the body
and subsequently to the brain, the power of discerning thinking would be left to
the flesh and to the blood vessels; it would reach the brain in a hot and no longer
pure state but mixed with moisture from the flesh and from the blood so that it
would no longer be accurate. I therefore state that the brain is the interpreter of
consciousness.
The diaphragm (phrenes), however, does not have the right name, but it has
got this by chance and through convention. I do not know in virtue of what
the diaphragm can think and have consciousness (phronein), except that if a man
suddenly feels pleasure or pain, the diaphragm leaps up and causes throbbing,
because it is thin and under greater tension than any other part of the body, and
it has no cavity into which it might receive anything good or bad that comes
upon it, but because of the weakness of its structure it is subject to disturbance
by either of these forces, since it does not perceive faster than any other part
of the body. Rather, it has its name and reputation for no good reason, just
as parts of the heart are called auricles though they make no contribution to
hearing.
Some say that we owe our consciousness to our hearts and that it is the heart
which suffers pain and feels anxiety. But this is not the case; rather, it is torn just
like the diaphragm, and even more than that for the same reasons: for blood vessels
from all parts of the body run to the heart, and it encapsulates these, so that it can
feel if any pain or tension occurs in a human being. Moreover, it is necessary for the
body to shudder and to contract when it feels pain, and when it is overwhelmed by
joy it experiences the same. This is why the heart and the diaphragm are particularly
sensitive. Yet neither of these parts has any share in consciousness; rather, it is the
brain which is responsible for all these. ( 16 – 17 [ 6. 390 – 4 L.])^15
(^15) Translation Jones in Jones and Withington ( 1923 – 31 ) vol.i, modified; section divisions according to
Grensemann.