CHAPTER XI. 



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 recur 

 rence, 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 ; 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 ; though in many particular investigations the place 

 of the induction may be supplied by a prior deduction ; but the 

 premises 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 tendencies; 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 premises 

 on observation or experiment. Thus, if the subject be social 

 or historical phenomena, the premises of the Deductive Method 

 must be the laws of the causes which determine that class of 

 phenomena ; and those causes are human actions, together 

 with the general outward circumstances under the influence of 

 which mankind are placed, and which constitute man s posi 

 tion on the earth. The Deductive Method, applied to social 

 phenomena, must begin, therefore, by investigating, or must 

 suppose to have been already investigated, the laws of human 



