i\ PSYCHO-PHYSICAL PHENOMENA 457 



in the well-known instance of Felida X described by Azain 

 (1876), the primary self has no knowledge of the secondary, nor 

 the latter of the former. The two personalities that alternate 

 are wholly separate as regards memory. Personality A is in- 

 capable of recalling what took place during the period in which 

 personality B was active, and nice verxa ; the two personalities 

 mutually ignore each other, as if separated by an impermeable 

 diaphragm. As we have seen, no such impermeability exists 

 between conscious and subconscious activity, the supraliminal 

 and subliminal self of Myers. At each moment of life our 

 thoughts and actions are not only determined by external 

 sensations and conscious motives, but are largely influenced also 

 by obscure internal sensations and subconscious motives, which 

 are generically known as tendencies or instincts. There is a 

 constant interplay between the subconscious and conscious 

 activities, and the mind that is, our psychical personality as a 

 whole results from the continuous co-ordinated collaboration of 

 the conscious with the subconscious. 



However mysterious from the scientific point of view may 

 be the process which makes possible the disintegration of 

 the human mind into two distinct consciousnesses, coexistent 

 or successive, we can nevertheless state that it results from 

 two factors : abnormal dissociation of conscious from subconscious 

 psycho-physical processes, and abnormal functional exaltation of 

 the latter, or, better, of a portion of them, into a new conscious 

 psychical entity, i.e. a new and distinct personality or subliminal 

 ego. Probably the two factors stand in the reciprocal relation of 

 cause and effect : it can readily be imagined that dissociation 

 promotes exaltation, while, conversely, exaltation promotes or 

 determines the functional dissociation of the two portions of the 

 mind. 



P. Janet believed that disintegration of human personality 

 could only occur in states of nervous enfeebleinent, as in hysterics 

 who exhibit an imperfect unification and co-ordination of the 

 mental functions. Owing to this psycho -asthenia, hysterical 

 subjects are incapable of holding their personality aggregated in 

 an organic whole, and they consequently lose control of the 

 secondary personality. 



Experience does not, however, justify this limitation of 

 the phenomena of dissociated personality merely to pathological 

 conditions, particularly to hysteria. Janet himself has recently 

 changed his opinion, and admits the possibility of the existence 

 of the co-conscious in normal individuals. This, which he admits 

 as possible only, seems on the strength of a number of arguments 

 to be also probable. 



In every human being, even under perfectly normal conditions, 

 there is a more or less pronounced differentiation, sometimes an 



