How does one come to be the type one is?
Is it a result of the experiences one has as a child?
Or is one born with it - not meaning that type is in one's genes, but in an Eastern philosophical manner - according to which there is an existence before we came into this world, and when we come to this world, we carry a distinct set of potentialities. And often - though not necessarily - we are born in an environment that suits the fruition of those potentialities.
A few weeks ago, I put this question to the Jungian therapist Cheryl Fuller (who writes the blog Jung at Heart) and she wrote back that introversion and extraversion may be inborn, but the other functions are perhaps the result of our childhood experiences. I understand that these answers were tentative.
Jung himself, it seems, did not specify the answer to this question.
I feel more inclined towards the view that we are born with our primary function (in my case, introverted feeling, as I am an INFP), if not type. I say this more out of an intuitive understanding of people than any hard, logical reasons.
At the heart of this also lie some issues between my psychotherapist and myself. She often interprets my personality - for instance, my introversion - to be a result of stresses in childhood. I, rather believe, that I was an introvert in any case, but became more so, and more rigidly so because of the stresses. The early stresses did not create my personality, they only set in stone what may otherwise have been more fluid and manoueverable. The purpose of therapy, for me, is to get that freedom and manoueverability back, so that I can use whatever function (out of the 8 that Jung described), according to the need of the situation. Hence, to make a fine distinction, I am not the result of the childhood stresses, but the rigidity of my personality is.
I also find it curious that my mother is an introvert (introverted sensing, ISFJ most probably), and she has two brothers, who are also introverts (most probably both introverted feeling, INFPs). I am a rare type, and I even have to uncles who are that rare type! This seems to somewhat strengthen the argument for type being inborn, although I know that some people will consider this to point towards psychological learning from adults. My father and brother are ENFPs.