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CHAPTER XL 

 OF THE DEDUCTIVE METHOD. 



1. THE mode of investigation which, from the 

 proved inapplicability of direct methods of observation 

 and experiment, remains to us as the main source of 

 the knowledge we possess, or can acquire, respecting 

 the conditions, and laws of recurrence, of the more 

 complex phenomena, is called, in its most general 

 expression, the Deductive Method ; and consists of 

 three operations : the first, one of direct induction ; 

 the second, of ratiocination; and the third, of 

 verification. 



I call the first step in the process an inductive 

 operation, because there must be a direct induction 

 as the basis of the whole ; although in many particular 

 investigations the place of the induction may be 

 supplied by a prior deduction ; but the premisses of 

 this prior deduction must have been derived from 

 induction. 



The problem of the Deductive Method is, to find 

 the law of an effect, from the laws of the different 

 tendencies of which it is the joint result. The first 

 requisite, therefore, is to know the laws of those ten- 

 dencies ; the law of each of the concurrent causes : and 

 this supposes a previous process of observation or 

 experiment upon each cause separately ; or else a 

 previous deduction, which also must depend for its 

 ultimate premisses upon observation or experiment. 

 Thus, if the subject be social, or historical phenomena, 

 the premisses of the Deductive Method must be the 



