328 FALLACIES. 



Female, Rest and Motion, Straight and Curved, Light and 

 Darkness, Good and Evil, Square and Oblong . . . Aristotle 

 himself deduced the doctrine of four elements and other 

 dogmas by oppositions of the same kind.&quot; 



Of the manner in which, from premises obtained in this 

 way, the ancients attempted to deduce laws of nature, an 

 example is given in the same work, a few pages further on. 

 ft Aristotle decides that there is no void, on such arguments as 

 this. In a void there could be no difference of up and down ; 

 for as in nothing there are no differences, so there are none in 

 a privation or negation ; but a void is merely a privation or 

 negation of matter; therefore, in a void, bodies could not 

 move up and down, which it is in their nature to do. It is 

 easily seen &quot; (Dr. Whewell very justly adds) &quot; that such a 

 mode of reasoning elevates the familiar forms of language, 

 and the intellectual connexions of terms, to a supremacy 

 over facts ; making truth depend upon whether terms are 

 or are not privative, and whether we say that bodies fall 

 naturally.&quot; 



The propensity to assume that the same relations obtain 

 between objects themselves, which obtain between our ideas 

 of them, is here seen in the extreme stage of its develop 

 ment. For the mode of philosophizing, exemplified in the 

 foregoing instances, assumes no less than that the proper 

 way of arriving at knowledge of nature, is to study nature 

 itself subjectively ; to apply our observation and analysis 

 not to the facts, but to the common notions entertained of 

 the facts. 



Many other equally striking examples may be given of the 

 tendency to assume that things which for the convenience of 

 common life are placed in different classes, must differ in every 

 respect. Of this nature was the universal and deeply-rooted 

 prejudice of antiquity and the middle ages, that celestial and 

 terrestrial phenomena must be essentially different, and could 

 in no manner or degree depend on the same laws. Of the 

 same kind, also, was the prejudice against which Bacon con 

 tended, that nothing produced by nature could be successfully 

 imitated by man : &quot; Calorem solis et ignis toto genere differre ; 



