A post I made at INTJf. This is a useful artificial construct an ENTP friend and I worked on for awhile...It is sort of handy when trying to understand issues across the Te/Fi to Fe/Ti boundary. It is utter speculation and I dont think it is real, but the idea construct is very useful as a tool to appreciate why we might be so very different in how we communicate. All parties have the very best intents-but seem hardwired to work in different directions....thus inadvertantly offend one another endlessly. There is beauty in everyone, but since it doesnt match what we, as individuals, understand, we will call it by more ugly terms..

wrt biological basis of type:

Jung thought type was innate from birth.

As, I understand it, certain aspects of personality monitored by the big five seem to be present from birth.

I spoke with a researcher who studied type in infants/children and developed the MMTI-c. She said type trends can be seen as young as nine months.

As a mom, my two kids had very different personalities very young. As soon as they were born-very obvious differences in their behaviors could be noted. I have spoken with other moms familiar with typology or not and they agree that infants have very distinctive personality traits.

inheritance of type:
I have seen this topic come up many times on other boards. The pattern isnt an obvious one. You see odd trends in families, but an obvious pattern of inheritance doesnt pop out.

It makes my Ne spider sense tingle, but the patterns just are not concrete enough and there data is too speculative.

With MBTI types it always seemed kinda obvious that they should balance each other out and they sorta do.

But last year, as I learned about the Jungian functions, I started to see a pretty big split down the judging divide. Fe(Ti) and Te(Fi) both are ways of exerting control and insuring social stability for the group. They both form external bonds which pull people together. But on almost every score, the way they communicate seems to be in direct opposition to one another. Not in a balancing way, but in a way that insures frustration, hurt and confusion on both parts.

If you look at a bunch of Fe(Ti) users or Te(Fi) users in isolated groups, these communications diffs go away-and the groups become much more productive with less infighting and are quite stable. In my workplace people and divisions will self-sort into groups in this manner. Te doesnt NEED Fe and Fe doesnt NEED Te. (Look at corporate america as an example)

So why would humans have evolved to have judging strategies that directly conflict so badly, as it seems the conflict would destablize a social group, not stablize it?

I (and the ENTP) got this crazy ass idea awhile back that perhaps we have two societies (Te and Fe) inter-meshed on top of one another-thus destined to conflict and fight and interbreed. Inside our heads we have all 8 cognitive functions so both Fe and Te are innate biological potentials obviously, just unrealized-we pick one path or the other.

But why would the two societies ever be mixed? When I thought over Fe(Ti)-the patterns make beautiful sense for short term goal accomplishment and maximum sharing of resources-a small group with socialistic tendencies-like a hunter/gatherer society where all resources must be pooled and goals will be day to day survival via social reciprocality. Te(Fi) was more optimal for long term goal accomplishment-where resources must be stored and preserved, logistical planning is an absolute, and you are held responsible for providing your share own resources-a more agrarian society.

So it kinda left me wondering if there isnt an epigenetic switch that, based upon enviornmental triggers during pregnancy, toggles between the two. It might take a few generations to toggle, given the heritability of methylation patterns, but if an entire society was hunter-gatherer vs agrarian, we would be born with the optimal set of cognitive functions to optimize survival.

But nowdays, it is all mixed together. (yes, this idea is ridiculous and insane, but you did ask for speculation It'd be fun to study MBTI types of a hunter gatherer tribe though.)