156 ANNUAL REPORT SMITHSONIAN INSTITUTION, 193 2 



MIND AND INDETERMINISM 



I have, perhaps fortunately, left myself no time to discuss the 

 effect of indeterminacy in the phj^sical universe on our general 

 outlook. I will content myself with stating in summary form the 

 points which seem to arise. 



(1) If the whole physical universe is deterministic, mental deci- 

 sions (or at least effective mental decisions) must also be predeter- 

 mined. For if it is predetermined in the physical world, to which 

 your body belongs, that there will be a pipe between your lips on 

 January 1, the result of your mental struggle on December 31 as to 

 whether you will give up smoking in the New Year is evidently 

 predetermined. The new physics thus opens the door to indeter- 

 minacy of mental phenomena, whereas the old deterministic physics 

 bolted and barred it completely. 



(2) The door is opened slightly, but apparently the opening is not 

 wide enough. For according to analogy with inorganic physical 

 systems we should expect the indeterminacy of human movements 

 to be quantitatively insignificant. In some way we must transfer 

 to human movements the wide indeterminacy characteristic of atoms 

 instead of the almost negligible indeterminacy manifested by inor- 

 ganic systems of comparable scale. I think this difficulty is not 

 insuperable, but it must not be underrated. 



(3) Although we may be uncertain as to the intermediate steps we 

 can scarcely doubt what is the final answer. If the atom has in- 

 determinacy, surely the human mind will have an equal indeter- 

 minacy; for we can scarcely accept a theory which makes out the 

 mind to be more mechanistic than the atom. 



(4) Is the human will really more free if its decisions are swayed 

 by new factors born from moment to moment than if they are the 

 outcome solely of hereditj^, training and other predetermining 

 causes ? 



On such questions as these we have nothing new to say. Argu- 

 ment will no doubt continue " about it and about." But it seems to 

 me that there is a far more important aspect of indeterminacy. It 

 makes it possible that the mind is not utterly deceived as to the mode 

 in which its decisions are readied. On the deterministic theory of 

 the physical world my hand in writing this address is guided in a 

 predetermined course according to the equations of mathematical 

 physics; my mind is unessential — a busybody who invents an irrele- 

 vant story about a scientific argument as an explanation of what my 

 hand is doing — an explanation which can only be described as a 

 downright lie. If it is true that the mind is so utterly deceived in 

 the story it weaves round our human actions, I do not see where 



