iii. 10. ^ 83 



as also with the liver, spleen, and kidneys. The latter are 

 "separated from the former by the midriff or, as some call it, the 

 Phrenes. This divides off the heart and lung, and as already 

 said ^is called Phrenes in sanguineous animals, alP of which 

 have a midriff, just as they all have a heart and a liver. For 

 they require a midriff to divide the region of the heart from 

 the region * of the stomach, so that the centre wherein abides 

 the sensory soul may be undisturbed, and not be overwhelmed, 

 directly food is taken, by its up-steaming vapour ^ and by the 

 abundance of heat then superinduced.^ For it was to guard 

 against this that nature made a division, constructing the midriff 

 as a kind of partition-wall and fence, and so separated the nobler 

 from the less noble parts, in all cases where a separation of 

 upper from lower was possible.* For the upper part is the 

 more^ honourable, and is that for the sake of which the rest 

 exists ; while the lower part exists for the sake of the upper 

 and constitutes the necessary element in the body, inasmuch as 

 it is the recipient of the food. 



That part of the midriff which is near the ribs is somewhat 

 fleshy and thick ; but the central part has more of a membranous 

 character, for this structure gives it strength and capability of 

 extension. Now that the midriff is as it were a curtain or 

 screen to prevent heat mounting up from below, is shown by 

 what happens, should it, owing to its proximity to the stomach, 

 attract thence the hot and residual fluid. For when this occurs 

 there ensueS forthwith a marked disturbance of intellect and of 

 sensation. It is indeed because of this that the midriff is called^ 

 Phrenes, as though it. had some share in the process of thinking, 

 for which the Greek term is PJironein. In reality however it 

 has no part whatsoever itself in the matter, but, lying in close 

 proximity to organs that have, it brings about the manifest 

 changes of intelligence in question by acting upon them. This 

 too explains why its central part is thin. For though this is in 

 some measure the result of necessity, inasmuch, as those portions 

 of the fleshy whole which lie nearest to the ribs must necessarily 

 be fleshier than the rest,'' yet besides this there is a final cause, 

 namely to give it as small a proportion of moisture as possible ; 

 for, had it been made of flesh throughout, it would have been 

 more likely to attract and hold a large amount of fluid. That 

 rapid heating of it affects sensation in a notable manner is 

 673 a. 



