Enioi || d' autôn kai rhêtôs apephênanto mêdemian einai 29 tês psychês dynamin, hê logizometha, all' hypo tôn aisthêtôn agesthai pathôn hêmas kathaper boskêmata pros mêden ananeusai mêd' anteipein dynamenous. kath' hous dêlonoti kai andreia kai phronêsis kai sôphrosynê kai enkrateia lêros esti makros kai philoumen out' allêlous oute ta engona kai tois theois ouden hêmôn melei. kataphronousi de kai tôn oneiratôn kai tôn oiônôn kai tôn symbolôn kai pasês astrologias, hyper hôn hêmeis men idia di' heterôn grammatôn epi pleon eskepsametha peri tôn Asklêpiadou tou iatrou skopoumenoi dogmatôn. enesti de tois boulomenois kakeinois men homilêsai tois logois kai nyn d' êdê skopein, hôsper tinôn dyoin hodôn hêmin prokeimenôn, hopoteran beltion esti trepesthai. Hippokratês men gar tên proteran rhêtheisan etrapeto, kath' hên hênôtai men hê ousia kai alloioutai kai sympnoun holon esti kai syrrhoun to sôma kai hê physis hapanta technikôs kai dikaiôs prattei dynameis echousa, kath' has hekaston tôn moriôn helkei men || eph' heauto 30 ton oikeion heautô chymon, helxan de prosphyei te panti merei tôn en hautô kai teleôs exomoioi, to de mê kratêthen en toutô mêde tên pantelê dynêthen alloiôsin te kai homoiotêta tou trephomenou katadexasthai di' heteras au tinos ekkritikês dynameôs apotribetai. XIII Now the extent of exactitude and truth in the doctrines of Hippocrates may be gauged, not merely from the way in which his opponents are at variance with obvious facts, but also from the various subjects of natural research themselves--the functions of animals, and the rest. For those people who do not believe that there exists in any part of the animal a faculty for attracting _its own special quality_[80] are compelled repeatedly to deny obvious facts.[81] For instance, Asclepiades, the physician,[82] did this in the case of the kidneys. That these are organs for secreting [separating out] the urine, was the belief not only of Hippocrates, Diocles, Erasistratus, Praxagoras,[83] and all other physicians of eminence, but practically every butcher is aware of this, from the fact that he daily observes both the position of the kidneys and the duct (termed the ureter) which runs from each kidney into the bladder, and from this arrangement he infers their characteristic use and faculty. But, even leaving the butchers aside, all people who suffer either from frequent dysuria or from retention of urine call themselves "nephritics,"[84] when they feel pain in the loins and pass sandy matter in their water.