CAUSE AND EFFECT— PROBABILITY 123 



explain the why of the motion. If I grant that my will 

 set the stone in motion, I cannot suppose it to continue 

 in motion for the same reason, for any amount of willing 

 after the stone has left my hand will not, in the majority 

 of cases, be in the least able to influence its motion. 

 Hence, even in motion started by a conscious being, 

 we have at once a mystery. My will might explain 

 the origin, it cannot explain the continuance of the 

 motion. If will is to help us at all, we must postulate 

 it as producing motion at every stage. But clearly this 

 will is not my will ; it must be some other will. Here 

 we are only restating the solutions of primitive man with 

 his spiritualism behind nature, of Schopenhauer with his 

 undefined will behind all phenomena, of Aristotle when 

 he says God moves all things. But this solution in- 

 volves an extension of the notion of will beyond the 

 sphere where we may legitimately infer its existence — 

 i.e. beyond the physiological structure with which, in our 

 experience, we have always found it associated. Like 

 the hypothesis of force it postulates an unthinkable x 

 outside sense -impressions. It carries us no- whither. 

 Will cannot, therefore, be looked upon as necessitating a 

 sequence of motion, any more than what we have termed 

 a secondary cause, for in the great majority of cases it 

 will be supposed to start a motion, it cannot enforce its 

 continuance in a particular sequence, and so far as the 

 will is concerned the motion might cease at its birth. 



§ 6. — Will as a Secondary Cause 



Will thus appears, like the secondary cause, as a stage 

 in the routine of perceptions. Our experience shows us 

 that in the past an act of will occurred at a certain stage 

 in a routine of perceptions, but we cannot assert that 

 there was anything in the act itself which enforced the 

 stages which followed. Does will, however, differ on 

 closer analysis from other secondary causes in being the 

 first stage of an observed routine ? This leads us to our 

 second question (p. 122), and the answer to it is really 



