I don't believe we are born with it.
If you ask me, it's not a coincidence that more than 75% of the population is comprised of Ss, and that the Ns that roam boards such as this one are usually people coming from environments and societies that don't frown upon abstract thinking (N) as much. Meaning if you go to developing countries you're bound to found higher percentages of Ss (this says nothing about intellegence, but as abstract as it is, it makes sense that N sensibilities would develop more naturally in a country like the US for instance), since a more concrete and down-to-earth mindset is needed in order to survive even.
I also don't think it is a coincidence that 75% of the population is sensor and it doesn't conflict with the my genetic theory.
Say you have two parents, one with brown eyes "B" and one with blue eyes 'bl'. Lets say for the purposes of this example that the father carries a recessive blue eye gene. This would make the father dom brown (B) with recessive blue (bl) or Bbl. Since blue eyes is a recessive trait, for it to manifest it would need to be matched with another recessive blue at conception. Since the mother shows a dominant recessive trait, she would carry double-recessive genes or 'blbl'.
Because of the way gene combination works during conception, their child would have a one in four chance to have blue eyes because the recessive blue eye trait needs to be doubled with another recessive blue to get a child with blue eyes. There would be a 75% chance of the combination B from the father and bl from the mother resulting in Bbl and brown eyed child because of the presence of a gene for a dominant trait and a 25% chance of a blbl combination or blue eyes.
The minority status of intuition in society can simply be explained by it being controlled by a recessive gene and this would explain why its also possible to get a family of mixed sensors and intuitives.
I'm open to the idea that we all have genetic predispositions, but as the ENFP that I am, and looking at my background and life story, I can see a direct correlation between my well developed Ti (my 3rd strongest function) and my career choices (which quite frankly are not really aligned with my personal likes that much) - science. So, yes...
Do you mean extraverted thinking? Te is the third function for ENFPs.
I don't know what you mean by static personality types (could you please clarify?) but as far as function preference, like I hinted at earlier, I believe early childhood is the most important phase in a person's life.
What I mean by static personality type is that even though we become actualized as we grow older by gaining mastery of other cognitive functions, we still retain our base personality type. The first four functions still serve their purpose as preferred decision making, information gathering function, etc. For example, in an INFJ, Ni,Fe,Ti and Se had a genetic head-start. In the real world we are never developing just one function at a time, but all at once as each function reacts to nearly simultaneously external stimuli. Since the cognitive functions are growing and forming connections simultaneously, the initial leg up those cognitive functions were given can never be overcome.
Also take into account the fact that humans tend to live in their comfort zones until forced to do otherwise. Since the weaker the function the harder it is to access (perhaps by the small number of neural connections limiting ease of impulse transfer), our stronger functions would seem more comfortable and therefore would naturally get more use, tilting the scales even further in their direction.
It also seems impossible from all of my studies for a cognitive function surpass your dominant or at least take on its role. I haven't quite worked out what biological reason a specific function is designated as captain of the ship; it's still something I'm turning over in my head.
Funny thing being, that I choose computer related courses since they were the closest thing I had to game development, which in turn ensured I studied stuff
I really disliked, and that didn't come naturally to me, like programming, for example, which, I'm pretty sure, was the primary reason why I developed my Ti so much. Moral of the story being - if I hadn't had that chance meeting with that videogame when I was a kid, Ti would probably not be my third strongest function today
Typically extraverted thinking gets more use in programing and computer science in general.
An extraverted thinker going about the process of programing an application would probably do a lot of planning ahead, implement his plan and then begin be forced to use Ti to deal with bugs and such. An extraverted thinker would be more likely to utilize programing flow charts for exmaple.
A purely intraverted thinking approach to programing would be a tendency to just pick a point and dive in, the code growing and evolving as problems are encountered and overcome. Intraverted thinking is a more organic, unconscious, trial and error process while Extraverted thinking deals with logic and by moving in a step by step, logical fashion.
If i had my cognitive function book handy i'd quote it directly, but it's currently loaned out to my girlfriend...