THE HUMAN WILL 



is so far from being voluntary that a considerable 

 effort of will is necessary to prevent it from taking 

 place. 



It is to the illustrious Descartes, renowned alike 

 as mathematician and metaphysician, that we owe 

 the discovery of reflex action, which is now known 

 to play such a part in physiology and psychology. 



When we come to examine the nervous system 

 of one of the higher animals or of man we find 

 that it may be regarded as an infinitely complex 

 congeries of reflex arcs, to be numbered by at least 

 thousands of millions. But each sensory nerve- 

 fibre that constitutes the ingoing half of each of 

 these reflex arcs may convey a stimulus that will 

 issue in action in any one or any group of the 

 voluntary or involuntary muscles of the body. 

 Under varying conditions, a blow on a given area 

 of your leg may cause you to advance it by way of 

 offence, to withdraw it by way of defence, to start 

 running in one of many directions, to use your arms 

 pugnaciously or to grasp some supporting object 

 with them, to scream or to laugh, to curse or to 

 pray the outgoing or motor half of the reflex 

 arc may thus vary. Yet, in health, the "will" is 

 not divided; you will definitely do one of these 

 things and not another ; you will not simultaneously 

 attempt half a dozen incompatible acts. Let us 

 take a simple but most significant instance. Two 

 objects are simultaneously presented to your vision. 

 Each of them sends an impulse from the part of 

 the retina struck by the rays of light that make it 

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