172 Human Personality. 



consciousness ceases until they resume contact. If the 

 blow was heavy, it is never resumed. 



So ephemeral a thing is this self-conscious personality, 

 this soul of man. And at best it is intermittent, with the 

 alternate lighting and darkening of the terrestrial hemis- 

 pheres. Once in twelve hours it must stop in order that 

 the neurons may rest from the stress caused by their uni- 

 fication as mind. The self-conscious personality is as 

 much lost in sound sleep, as in organic death, only in the 

 one case sentient contact is resumed, in the other not. 



Moreover, this personality varies in degree according as 

 the brain cells come fully into sentient relationship, or 

 but partially. In certain degrees of somnolence, a part of 

 the brain cells appear to join contact, giving rise to 

 dieanis. A dream implies a minor degree of self -con- 

 sciousness ; a part of the neurons are in contact ; but the 

 more complete personality of waking hours is not estab- 

 lished. To be fully self-conscious, all the lobes, convolu- 

 tions, and tracts of cells must be involved. This is best 

 accomplished after the cells have rested, after sleep, when 

 each cell has for a time been withdrawn from the consen- 

 tient hund and has had time to attend to its personal 

 wants, nutrition and the expulsion of waste products which 

 accumulate while the cells are consecrating their energies 

 and merging their self-lives in the greater life of the organ- 

 ism. The sentient contact is less perfect toward the end of 

 the day, when the neurons are fatigued. The personality 



