GENERATION OF ANIMALS, II. viii. 



such circumstances tiro softs give rise to one hard, just as 

 bronze mixed with tin does. In the first place, he has 

 got the reason wTong in the case of bronze and tin 

 (see what I have ^%■ritten about this in the Problems),'^ 

 and further, to put the objection generally, the 

 principles from which he starts his argument are not 

 intelhgible.'' How do the hollows and soUds by 

 " fitting on to one another " produce " the mixture 

 as of wine and water " ? This saying of his is over 

 our heads ; it is quite beyond our perception what 

 we are to understand by the " hollows " of wine and 

 water. Further, in point of fact, a horse is the off- 

 spring of two horses, an ass of two asses, a mule of a 

 horse and an ass — i.e., its sire is a horse and its dam 

 an ass or vice versa, ^^^ly is it then that a horse and 

 an ass produce something so " dense " that the off- 

 spring formed is infertile, whereas the offspring 

 resulting from a male and female horse or from a 

 male and female ass is not infertile ? After all, the 

 secretion of both the male and of the female horse is 

 " soft," and both sexes of the horse unite ^\"ith asses 

 of the opposite sex. The reason why in both these 

 cases the offspring produced is infertile, according to 

 Empedocles, is because the one product of the two 

 soft " seeds " is something (" dense ">. But then so 

 it ought to be when the two seeds originate from two 

 horses. If only one sex of the horse united with the 

 ass, it would be open to Empedocles to say that the 

 cause of the mule's infertihty was the dissimilarity ^of 

 that one sex to the semen of the ass. In fact, how- 

 ever, there is no difference in quality between the 

 seed of the ass Mith which it unites (to form a mule) 



" No such reference can be found. 

 » Cf. Anal. Post. 100 b 9. 



251 



