PHILOSOPHY OF INDUCTIVE INFERENCE. 257 



under which a perpetual motion, that is, a perpetual 

 source of self-created energy might exist. d The larger 

 part of the philosophic world has long held that in mental 

 acts there is free will in short, self-causation. It is in 

 vain to attempt to reconcile this doctrine with that of an 

 intuitive belief in causation, as Sir W. Hamilton candidly 

 allowed. 



It is quite obvious, moreover, that to assert the exist- 

 ence of a cause for every event, cannot do more than 

 remove into the indefinite past the inconceivable fact and 

 mystery of creation. At any given moment matter and 

 energy were equal to what they are at present, or they 

 were not ; if equal, we may make the same inquiry con- 

 cerning any other moment, however long prior, and we 

 are thus obliged to accept one horn of the dilemma ex- 

 istence from infinity, or creation at some moment. This 

 is but one of the many cases in which we are compelled 

 to believe in one or other of two alternatives, both incon- 

 ceivable. My present purpose, however, is to point out 

 that we must not confuse this supremely difficult question 

 with that into which inductive science inquires on the 

 foundation of facts. By induction we gain no certain 

 knowledge ; but by observation, and the inverse use of 

 deductive reasoning, we estimate the probability that an 

 event which has occurred was preceded by conditions of 

 specified character, or that such conditions will be followed 

 by the event. 



Definition of the Term Cause. 



Clear definitions of the word cause have been given by 

 several philosophers. Hobbes has said, ' A cause is the 

 sum or aggregate of all such accidents both in the agents 



d 'Cambridge Philosophical Transactions/ [1830] vol. iii. pp. 369- 

 372. 



S 



