3H CAUSATION 



insurance company. Theoretically the one uncertainty 

 might lead to the other, as when the fate of millions 

 turned on the murders at Sarajevo. But the hypothesis 

 that the mind operates through two or three key-atoms 

 in the brain is too desperate a way of escape for us, and 

 I reject it for the reasons already stated. 



It is one thing to allow the mind to direct an atom 

 between two courses neither of which would be im- 

 probable for an inorganic atom; it is another thing to 

 allow it to direct a crowd of atoms into a configuration 

 which the secondary laws of physics would set aside as 

 "too improbable". Here the improbability is that a 

 large number of entities each acting independently 

 should conspire to produce the result; it is like the 

 improbability of the atoms finding themselves by chance 

 all in one half of a vessel. We must suppose that in the 

 physical part of the brain immediately affected by a 

 mental decision there is some kind of interdependence 

 of behaviour of the atoms which is not present in 

 inorganic matter. 



I do not wish to minimise the seriousness of admitting 

 this difference between living and dead matter. But 

 I think that the difficulty has been eased a little, if it 

 has not been removed. To leave the atom constituted as 

 it was but to interfere with the probability of its un- 

 determined behaviour, does not seem quite so drastic 

 an interference with natural law as other modes of 

 mental interference that have been suggested. (Perhaps 

 that is only because we do not understand enough about 

 these probabilities to realise the heinousness of our 

 suggestion.) Unless it belies its name, probability can 

 be modified in ways which ordinary physical entities 

 would not admit of. There can be no unique probability 

 attached to any event or behaviour; we can only speak 



