In Robert C. Smith's book The Wounded Jung, we read
Jung candidly tells us that the play and counterplay between what he terms his own Personalities No. 1 and No. 2 ran throughout his entire lifetime (45). He insists that his experience of dual person¬ alities has nothing to do with a split or dissociation in the ordinary medical sense. But is he to be taken seriously in this regard? Quite amazingly, he argues that this same phenomenon is played out in the life of every individual.
Jungians commentators usually shroud in mystery and awe the episode when Jung noticed at a young age that he had two personalities. It conforts them in their view of the magical and wonderful world of the Jungian mystique. They are in such a state of admiration that they are unable to find out the logical meaning of Jung's assertion. Jung's two personalities are the normal differentiation of his dominant and auxiliary cognitive functions.
Smith adds
Jung explains to the reader of Memories that his No. 1 Personality gave him a place in time, but that Personality No. 2 provided a sense of the imperishable, of peace and solitude, and was of supreme importance. In his view this latter personality is what related him to the eternal and archetypal dimension of existence. Jung confesses:
“Somewhere deep in the background I always knew that I was two persons. One was the son of my parents, who went to school and was less intelligent, attentive, hardworking, decent and clean than many other boys. The other was grown up—old, in fact—skeptical, mistrustful, remote from the world of men but close to nature . . . and above all close to the night, to dreams, and to whatever ‘God’ worked directly in him”
Jung was probably an INTJ. His dominant cognitive function was Introverted Intuition and his auxiliary function was Extraverted Thinking. His personality No. 1 was his extraverted cognitive function that gave him a place in the world. His personality No. 2 was his introverted cognitive function that provided him a sense of peace and solitude.
It is no surprise that Jung was brought early to distinguish his two cognitive funcions because his mother taught him so. She already noticed her two personalities and was sspeaking about them. The young Carl only followed her teaching and eventually produced a theory on those two different orientations of consciousness. That was the foudation of his 1921 Psychological Types.
Anyone who reflect on his or her childhood is able to find the two personalities at play. One is extraverted and the other, introverted. One is a function of Perception and the other, a function of Judgment. The same observation can easily be made in the present moment if one is taught how to do so. It is that teaching that is the important factor, not the two personalities.
We know that Jung also found that his mother had two personalities. During the day, she was an extraverted woman who liked talking and was cheerful. At night, she was more introverted and seemed strange to the young Carl. The two different psychological types are a normal occurrence and not the only characteristic of the young Carl Jung. Everybody has them.