MBTI – Cognitive Function DEVELOPMENT


PREVIOUS: Attractivenessthe INF

SITEs: “Learn all about MBTI
▪︎ MANY links at “
Mental Symmetry

Birth to about age 13
We develop our DOM function. It’s the most obvious in children, & the one they will have the most control of throughout life. Glimpses of their auxiliary function will be seen as well, but underdeveloped & not quite balanced

13 to about 21
The AUX function develops, in support of the DOM. For Introverts, the AUX will be shown to the outside world, while the Dom is less visible – at first

DOM & AUX are the 2 most relied-on functions, & make up about 90% of our personality type

21 to mid-40s
The TER function develops. While this will never be as strong as the first 2, it will help balance them out if developed properly

40s through 70s
The INF is gradually developed. For many it will always be a weak point in the personality, since it’s rarely going to be as easy to use as the first 2. However, with proper practice & persistence, we can greatly benefit from its addition

✦ Normal personality growth happens in stages which correspond to the order of our specific functional stack, so by observation we can see which stage someone happens to be in, because chances are they’ll gravitate to people who have a weaker function higher up in their stack, in an unconscious attempt to learn from them.

EXP: An INTP (Ti-Ne-Si-Fe) who is having trouble using their Si-Tert successfully (lazy, sloppy, procrastinating….) may hang out with an ESFJ (Fe-Si-Ne-Ti) or an ISFJ (Si-Fe-Ti-Ne) to see how those people organize / structure their life.

Se will look to SPs or NPs for adaptability
Si will look to SJs or NJs for discipline

Ne will look tot NPs or SPs for openness
Ni will look to NJs or SJs for expertise

Te will look to TJs or TPs for competence
Ti will look to TPs or TJs for self-possession

Fe will look to FJs or FPs for compassion
Fi will look to FPs or FJs for moral virtue

✦ Any Undeveloped Function (BY eilamona )
▸ Usage is in its raw, basic form
▸ Usage is usually one-dimensional & not adaptable (like: an undeveloped inferior Ne who only sees negative possibilities)
▸Is present but untrusted & undervalued by the user

▸ User who doesn’t recognizes an undeveloped function’s influence on their thought process will have little or no control over it
▸ When it becomes prominent, usually under pressure, the undeveloped function is explosive & uncontrollable (INF in “Grip”)

Any Developed Function
▸ It’s multi-faceted, so can be used in many complex ways
▸ It easily adapts to & supports many different life situations

▸ The user has mastered the function, trusts their ability to use it in their thinking, & consciously consults it often
▸ Being comfortable with the function, the user relies on it to make important decisions in life

Any Unhealthy Function
It’s used in negative, unproductive & destructive ways, toward self & others
▸ It’s often used in isolation, not interacting with other functions of opposite E / I preferences (such as a DOM/TER loop with an undeveloped AUX), unless other functions are also unhealthy

EXP: An INFJ girl with an unhealthy Ni-Fe “knows” that her friend is dating a ‘wrong’ person who’s likely to cheat. So she plans & proceeds to sabotage the friend’s relationship through manipulation, because she’s sure she knows what’s best, without asking what the friend actually wants (true story)

Any Healthy Function
It’s used in beneficial, productive ways (to self/ others)
▸ It works well with other functions around it

 If the same INFJ girl has a healthy Ni-Fe, she may notice that her friend’s new romantic partner is very non-committal. She cares about her friend & her ‘wants’, so decides to talk to her about it.
It turns out the friend is already aware, & explains the partner will be leaving the country in a few months anyway, so it’s ok. The INF respects her friend’s choice, and will be supportive in future if/when she may have relationship problems, but will never be the cause of them!

NEXT: Function overview

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.