pikrocholois echthron, tois de phlegmatôdesi philion; heni de logô tois men thermois sômasin ê dia physin ê dia noson ê di' hêlikian ê di' hôran ê dia chôran ê di' epitêdeuma cholês gennêtikon, haimatos de tois enantiois. Kai mên ouk endechetai tauton edesma tois men cholên gennan, tois d' haima mê ouk en tô sômati tês geneseôs autôn epiteloumenês. ei gar dê oikothen ge kai par' heautou tôn edesmatôn hekaston echon kai ouk en tois tôn zôôn sômasi || metaballomenon egenna tên cholên, en 125 hapasin an homoiôs autên tois sômasin egenna kai to men pikron exô geuomenois ên an oimai cholês poiêtikon, ei de ti glyky kai chrêston, ouk an oude to brachytaton ex autou cholês egennato. kai mên ou to meli monon, alla kai tôn allôn hekaston tôn glykeôn tois proeirêmenois sômasi tois di' hotioun tôn eirêmenôn thermois ousin eis cholên hetoimôs existatai. Kaitoi taut' ouk oid' hopôs exênechthên eipein ou proelomenos all' hyp' autês tou logou tês akolouthias anankastheis. eirêtai d' epi pleiston hyper autôn Aristotelei te kai Praxagora tên Hippokratous kai Platônos gnômên orthôs exêgêsamenois. IX For this reason the things that we have said are not to be looked upon as proofs but rather as indications of the dulness[271] of those who think differently, and who do not even recognise what is agreed on by everyone and is a matter of daily observation. As for the scientific proofs of all this, they are to be drawn from these principles of which I have already spoken[272]--namely, that bodies act upon and are acted upon by each other in virtue of the Warm, Cold, Moist and Dry. And if one is speaking of any activity, whether it be exercised by vein, liver, arteries, heart, alimentary canal, or any part, one will be inevitably compelled to acknowledge that this activity depends upon the way in which the four qualities are blended. Thus I should like to ask the Erasistrateans why it is that the stomach contracts upon the food, and why the veins generate blood. There is no use in recognizing the mere fact of contraction, without also knowing the _cause_; if we know this, we shall also be able to rectify the failures of function. "This is no concern of ours," they say; "we do not occupy ourselves with such causes as these; they are outside the sphere of the _practitioner_,[273] and belong to that of the _scientific investigator_."[274] Are you, then, going to oppose those who maintain that the cause of the function of every organ is a natural eucrasia,[275] that the dyscrasia is itself known as a _disease_, and that it is certainly by this that the activity becomes impaired? Or, on the other hand, will you be convinced by the proofs which the ancient writers furnished? Or will you take a midway course between these two, neither perforce accepting these arguments as true nor contradicting them as false, but suddenly becoming