CAUSATION AND TIME'S ARROW 295 



practicable to obtain the data of prediction, but because 

 no data connected causally with our experience exist. 

 It will be necessary to defend so remarkable a change of 

 opinion at some length. Meanwhile we may note that 

 science thereby withdraws its moral opposition to free- 

 will. Those who maintain a deterministic theory of 

 mental activity must do so as the outcome of their study 

 of the mind itself and not with the idea that they are 

 thereby making it more conformable with our experi- 

 mental knowledge of the laws of inorganic nature. 



Causation and Time's Arrow. Cause and effect are closely 

 bound up with time's arrow; the cause must precede 

 the effect. The relativity of time has not obliterated this 

 order. An event Here-Now can only cause events in the 

 cone of absolute future; it can be caused by events in 

 the cone of absolute past; it can neither cause nor be 

 caused by events in the neutral wedge, since the neces- 

 sary influence would in that case have to be transmitted 

 with a speed faster than light. But curiously enough this 

 elementary notion of cause and effect is quite incon- 

 sistent with a strictly causal scheme. How can I cause 

 an event in the absolute future, if the future was pre- 

 determined before I was born? The notion evidently 

 implies that something may be born into the world at 

 the instant Here-Now, which has an influence extending 

 throughout the future cone but no corresponding 

 linkage to the cone of absolute past. The primary laws 

 of physics do not provide for any such one-way linkage; 

 any alteration in a prescribed state of the world implies 

 alterations in its past state symmetrical with the altera- 

 tions in its future state. Thus in primary physics, which 

 knows nothing of time's arrow, there is no discrimina- 

 tion of cause and effect; but events are connected by a 



