VTII.] ERRORS ATTRIBUTED TO ARISTOTLE. 197 



to refer to their observations, and to explain why, 

 in his judgment, they fell into the errors which he 

 corrects. 



Aristotle's knowledge, in fact, appears to have 

 stood in the same relation to that of such men as 

 Polybus and Diogenes of Apollonia, as that of 

 Herophilus and Erasistratus did to his own, so far 

 as the heart is concerned. He carried science a step 

 beyond the point at which he found it ; a meritorious, 

 but not a miraculous, achievement. What he did, 

 required the possession of very good powers of 

 observation ; if they had been powers of the highest 

 class, he could hardly have left such conspicuous 

 objects as the valves of the heart to be discovered 

 by his successors. 



And this leads me to make a final remark upon a 

 singular feature of the " Historia Animalium." As a 

 whole, it is a most notable production, full of accurate 

 information, and of extremely acute generalisations of 

 the observations accumulated by naturalists up to 

 that time. And yet, every here and there, one 

 stumbles upon assertions respecting matters which lie 

 within the scope of the commonest inspection, which 

 are not so much to be called errors, as stupidities. 

 What is to be made of the statement that the sutures 

 of women's skulls are different from those of men ; 

 that men and sundry male animals have more teeth 

 than their respective females ; that the back of the 

 skull is empty ; and so on ? It is simply incredible 

 to me, that the Aristotle who wrote the account of the 

 heart, also committed himself to absurdities which 



