ch. i.] MATTER, MOTION, AND FORCE. 289 



of force, that there is an invariable order of succession 

 between the totality of phenomena which exist at any given 

 instant and the totality of phenomena which exist at the 

 next succeeding instant. No matter how many special orders 

 of sequences may interlace to form the grand web of sequent 

 phenomena, the order of sequences, both separately and in 

 the aggregate, must be invariable. In complicated mechanical 

 problems, where many forces are involved, we proceed to 

 eliminate one after another by means of the principle of the 

 parallelogram of forces, until at last we retain but two 

 differently located forces, the resultant of which is easily 

 calculable. So, in the most complex cases of causation to be 

 found in nature — as, for instance, in those concerned in the 

 development of the moral character of individuals — if we 

 possessed the means of measuring quantitatively the ratio of 

 each set of antecedents to its set of consequents, we might 

 eliminate one group after another, until at length a necessary 

 relation of sequence would be disclosed between the resultant 

 group <f antecedents and consequents. As Mr. Mill observes : 

 " For every event there exists some combination of objects 

 or events, some given concurrence of circumstances, positive 

 and negative, the occurrence of which is always followed by 

 that phenomenon. We may not have found out what this 

 concurrence of circumstances may be ; but we never doubt 

 that there is such a one, and that it never occurs without 

 having the phenomenon in question as its effect or con- 

 sequence." 1 Our unhesitating assurance that " there is a law 

 to be found if we only knew how to find it " is thus the 

 foundation of all the canons of inductive logic. The 

 uniformity of the laws of nature is elsewhere called by Mr. 

 Mill "the major premise of all inductions." The present 

 analysis further shows us that this uniformity of law is 

 resolvable into the persistence of relations among forces, and is 

 therefore an immediate corollary from the persistence of force. 

 1 System of Logic, 6 th fdit., vol. i. p. 367. 

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