326 INDUCTION. 



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 al- 

 ready investigated, the laws of human action, and those properties of out- 

 ward things by which the actions of human beings in society are deter- 

 mined. Some of these general truths will naturally be obtained by obser- 

 vation and experiment, others by deduction : the more complex laws of 

 human action, for example, may be deduced from the simpler ones; but 

 the simple or elementary laws will always, and necessarily, have been ob- 

 tained by a directly inductive process. 



To ascertain, then, the laws of each separate cause which takes a share 

 in producing the effect, is the first desideratum of the Deductive Method. 

 To know what the causes are which must be subjected to this process of 

 study, may or may not be difficult. In the case last mentioned, this first 

 condition is of easy fulfillment. That social phenomena depend on the acts 

 and mental impressions of human beings, never could have been a matter 

 of any doubt, however imperfectly it may have been known either by what 

 laws those impressions and actions are governed, or to what social conse- 

 quences their laws naturally lead. Neither, again, after physical science 

 had attained a certain development, could there be any real doubt where to 

 look for the laws on which the phenomena of life depend, since they must 

 be the mechanical and chemical laws of the solid and fluid substances com- 

 posing the organized body and the medium in which it subsists, together 

 with the peculiar vital laws of the different tissues constituting the organic 

 structure. In other cases, really far more simple than these, it was much 

 less obvious in what quarter the causes were to be looked for: as in the 

 case of the celestial phenomena. Until, by combining the laws of certain 

 causes, it was found that those laws explained all the facts which experi- 

 ence had proved concerning the heavenly motions, and led to predictions 

 which it always verified, mankind never knew that those were the causes. 

 But whether we are able to put the question before, or not until after, we 

 have become capable of answering it, in either case it must be answered ; 

 the laws of the different causes must be ascertained, before we can proceed 

 to deduce from them the conditions of the effect. 



The mode of ascertaining those laws neither is, nor can be any other 

 than the fourfold method of experimental inquiry, already discussed. A 

 few remarks on the application of that method to cases of the Composition 

 of Causes are all that is requisite. 



It is obvious that we can not expert to find the law of a tendency by 

 an induction from cases in which the tendency is counteracted. The laws 

 of motion could never have been brought to light from the observation of 

 bodies kept at rest by the equilibrium of opposing forces. Even where the 

 tendency is not, in the ordinary sense of the word, coimtei'acted, but only 

 modified, by having its effects compounded with the effects arising from 

 some other tendency or tendencies, we are still in an ixnfavorable position 

 for tracing, by means of such cases, the law of the tendency itself. It 

 would have been scarcely possible to discover the law that every body in 

 motion tends to continue moving in a straight line, by an induction from 

 instances in which the motion is deflected into a curve, by being compound- 

 ed with the effect of an accelerating force. Notwithstanding the resources 

 afforded in this description of cases by the Method of Concomitant Varia- 

 tions, the principles of a judicious experimentation prescribe that the law 

 of each of the tendencies should be studied, if possible, in cases in which 



