For those of you who can reason it out:
Why do you think you developed the dominant function you did? What impulses or reasons led to it? What, if anything, did it have to do with your inferior?
I'm not sure. I don't believe in the complete "blank slate", but I think it's a combination of nature and nurture. I believe I had natural tendencies for introverted judgment that my upbringing and environment allowed to flourish. But I'm not sure if I was naturally introverted thinking from the beginning or if that came later. But, by rifling through my memories (my earliest memory dates back to when I was three), I can't remember when I haven't been an introverted thinker.
I was always a quiet and laid-back child, but also very independent and low maintenance. I always wanted to do everything myself. I had incredible concentration even at a very young age. I could sit by myself for hours, playing or listening to my mom read to me and my siblings. My mom is Ni-dominant, and she said as a child she was very spacey and in her own world. But she said that while I was in my own world too, I was always very focused.
For as long as I can remember, I've been fascinated in how things work and why things are the way they are. I collected rocks, leaves, coins, shells. I had books on the classification of trees and stars, and my mom bought me these treasure chest books about Ancient China, Egypt, Greece and Rome. They had maps which had stickers that you had to find the right outline on the map to match to, and the Greece and Egypt ones had cipher wheels with the different alphabets or symbologies. I poured over these for hours at a time, and drew charts, and started created secret alphabets of my own. (I actually can pinpoint the beginning of my fascination with Linguistics to this). I would create stories in my head about what was like to live in those times. I had books about things like castles or the Titanic, about how they were built. My favorite part was the cross-section and the break-down of all the parts of the structure. I thrived on these things. My childhood was one rich with ideas and stories.
My introverted nature was encouraged; everyone in my immediate family is an introvert. I've never been particularly emotive nor had a lot of friends. My quiet nature did not serve me well in this case, and I've always marveled at the ease which everyone else seemed to travel through the world of relationships. This has followed me and my continued misadventures in this area have reinforced my aversion to it. Being detached and keeping to myself were not conducive to forming connections. In fact, I had such reign over my emotions, or perhaps avoidance of them, that, when I was 12 and had seemingly developed extreme anger issues out of the blue, it completely blind-sided my mom.