ARISTOTELIAN PHYSICS -15 



says, "from what is known to what is unknown." 

 This will not be denied ; but we can hardly follow 

 him in his inference. He adds, " we must proceed, 

 therefore, from universal to particular. And some- 

 thing of this," he pursues, "may be seen in lan- 

 guage ; for names signify things in a general and 

 indefinite manner, as circle, and by defining we un- 

 fold them into particulars." He illustrates this by 

 saying, " thus children at first call all men father, 

 and all women mother, but afterwards distinguish." 

 In accordance with this view, he endeavours to 

 settle several of the great questions concerning the 

 universe, which had been started among subtle and 

 speculative men, by unfolding the meaning of the 

 words and phrases which are applied to the most 

 general notions of things and relations. We have 

 already noticed this method. A few examples will 

 ' illustrate it further : Whether there was or was 

 not a void, or place without matter, had already been 

 debated among rival sects of philosophers. The an- 

 tagonist arguments were briefly these: There must 

 be a void, because a body cannot move into a space 

 except it is empty, and therefore without a void 

 there could be no motion : and, on the other hand, 

 there is no void, for the intervals between bodies 

 are filled with air, and air is something. These 

 opinions had even been supported by reference to 

 experiment. On the one hand, Anaxagoras and 

 his school had shown, that air when confined, re- 

 sisted compression, by squeezing a blown bladder, 



