Book 3
13
Now, mov ements like these come to an end fairly soon, but those resulting from internal irritants (e.g., in the administration of purgative drugs or in cholera) become much stronger and more lasting; they persist as long as the condition of thingsDiathesis. about the mouths of the veins continues, that is, so long as these continue to attract what is adjacent. For this conditionDiathesis. causes evacuation of the contiguous part, and that again of the part next to it, and this never stops until the extreme surface is reached; thus, as each part keeps passing on matter to its neighbour, the original affectionPathos. very quickly arrives at the extreme termination. Now this is also the case in ileus; the inflamed intestine is unable to support either the weight or the acridity of the waste substances and so does its best to excrete them, in fact to drive them as far away as possible. And, being prevented from effecting an expulsion downwards when the severest part of the inflammation is there, it expels the matter into the adjoining part of the intestines situated above. Thus the tendency of the eliminative faculty is step by step upwards, until the superfluities reach the mouth.
