REFLEX ACTION 215 



the power of co-ordinating the movements of the cells of 

 multicellular animals must have arisen before the evolution 

 of consciousness, and since many reflexes are not associated 

 with feeling, it is certain that reflex action in its beginnings 

 was evolved before mind. The term " reflex," as the deriva- 

 tion implies, is usually limited to actions which occur through 

 the medium of a more or less differentiated nervous system, 

 by means of which " afferent " or in-going impulses pass to, 

 and " efferent " or out-going impulses pass from a central 

 nervous mass. Movements which occur in the absence of 

 a differentiated nervous system, as in very low animals, have 

 been termed " protoplasmic," though the term " reflex " is 

 occasionally applied to them also. Accepting the limitation, 

 it is evident that mind was a new faculty, the evolution of 

 which was rendered possible by the antecedent evolution of 

 a differentiated nervous system a nervous system that near 

 its beginnings was devoted exclusively to reflex action. It 

 is very probable, therefore, that the first function performed 

 by mind in its most primitive form of sense-impressions, was 

 to initiate certain reflexes. As animals grew complex and 

 the reflexes numerous, definite sense-impressions served as 

 delicately discriminating, but potent stimuli to given reflexes 

 sparks which fatally exploded given stores of energy. 1 



366. None of the reflex actions of the individual are 

 initiated by his will. But many of them may, to a greater or 

 lesser extent, be inhibited by it. Thus power of voluntary 

 inhibition, whenever it occurs, is invariably associated with 

 pain, which with pleasure furnishes the springs of desire, of 

 will, of voluntary action. It is present only where it is 

 useful to the individual. Thus a man is quite unable to 

 control the movements of his heart, or the peristaltic move- 

 ments of his stomach and intestines. Under normal 

 circumstances he would derive no benefit from such control. 

 Certainly his remote unintelligent ancestors would have 

 derived none. But he is able to inhibit to a greater or 

 lesser extent, especially when the reflex impulse is somewhat 

 weak, the movements of certain other portions of his 

 alimentary canal, as well as such reflexes as breathing, 

 coughing, and winking. In such cases the exercise of 

 inhibition is associated with increasing pain or discomfort 



1 An attempt to associate mind in its beginnings with reflex action is 

 one thing. Quite a different thing would be an attempt to trace the 

 evolution of mind from that which was non-mental. The latter is not 

 attempted here. If we were able to trace mind from non- mental be- 

 ginnings we should know the exact nature of the connection between 

 mind and matter. 



