34 



Summary. 



HABIT AND INTELLIGENCE. 



[chap. 



The various uervous actions belonging to sentient and 

 mental life may be enumerated as — 



Enumera- 

 tion of 

 mental 

 actions. 



Mutual 

 relation 

 of the 

 nervous 

 organs of 

 mind. 



Sensation, 



Motor action, 



Consciousness (including Memory), 



Will, and 



Thought. 



Each of these has its own special nerve-fibres, and is 

 caused by the mutual action of the fibres and the ganglia 

 with which they are connected — or, in other words, by 

 nerve-currents flowing from the fibres into the ganglia, or 

 the converse. A current of one kind can determine the 

 production of a current of another kind, according to 

 definite laws. 



The position of the ganglia and nerve-fibres of mind 

 may be represented in the following diagramatic form : — 



Ganglionic substance of the cerel)rum. 

 Nerves of thought. 



^ 





Sensory ganglia. 



Motor ganglia, or 

 corpora striata. 



'S' 



Organs of sense. 



Voluntary muscles. 



Sensation. All mind begins with sensation : the first fact of mind 

 consists in currents flowing upwards from the external 



