Regardless of the internet's overall frequent misinterpretations of MBTI (I blame the elementary way it's often summarized; I'm much more into socionics theory than academic MBTI theory due to that socionics tends to flesh things out more and measures people's functions based on interrelations and behavior wrt cognition), graphs like these actually highlight the usage of functions well:
Whenever I type people/characters/whatsoever, I usually keep an eye out for dominant and tertiary functions. This image implies - but doesn't state - and I've also seen here and there, that the dominant and tertiary functions tend to be the most prominent in behavior. When I was first learning about cognitive functions, I'd read that the dominant function is the thing you use the most naturally, without question; the tertiary function is what you use without question, but not as
It's interesting, and paves a way to my theory of this:
(which I've also seen implied here and there among abstract posts about cognitive functions)
Dominant and tertiary functions are what you do
. Auxiliary and inferior functions are why
you do them.
Obviously I don't mean this literally; but it's more in that while you "externally" use either your dominant or tertiary function, your internal procedure is more keyed on the auxiliary and/or inferior function.
ExxJ vs IxxJ, and tertiary functions
When it comes to typing, this is why I tend to seek the tertiary function, or at least have a couple of contenders. (Usually I can distinguish the functions that are either dominant or tertiary; it's positioning that sometimes takes me a while.) I have seen typings of characters that I find to be obvious IxTJs as ExTJs, possibly because of the aggression of a Te. But in the case of STJs the characters I find to be "obvious" ISTJs do not have tertiary Ne at all
, because their Ne is something that they reject, or are hard to consolidate with, or only come during moments of panic - inferior at worst.
As for INTJs vs ENTJs, I think it's really a matter of taking into consideration that since INTJs have Te auxiliary
, it's a likelihood that in instances they are militant and emotionless, it's completely deliberate, whereas for an ENTJ it would just seem more "natural," as in the idea of them being otherwise is bizarre and unnatural to them. Contrary to popular belief, INTJs have more flavor in this area, both in this choice to exercise their auxiliary Te in an intentional way, and also
the tertiary Fi. People often talk about INTJs like they've forgotten that the INTJ's instinctive yet unnatural function is introverted feeling
. But we'll get to tertiary functions in any introvert later.
I find there to be similar issues between the I/E dichotomy with NFJs. (Hilariously enough, most people can at least distinguish an ISFJ from an ESFJ.) I have seen many characters/people - usually women, mind you - typed as ENFJs, when I would highly oppose the idea that the person in question has inferior Ti. It's because the thing about IxFJs is similar to that of IxTJs - their aggression or friendliness or whatever that may make them seem like their extroverted counterpart (i.e. leading with Fe or Te) when it's really not that simple. With an ExFJ, the constant awareness of others and how one's (or other's) behaviors affects others is, like the ExTJ, a natural mode. To think or behave otherwise is foreign concept to the ExFJ.
The IxFJ, like the IxTJ, is deliberately
friendly, or concerned about others, or what have you. They do not behave friendly and invested in others because it's their natural way of thinking, but because it's highly important to them. When interacting with an IxFJ, you get a stronger sense of how much they do (or don't) care about how others live their lives and interact with each other - plus, with that tertiary Ti, they're also awfully good at justifying whatever they say due to this. On the other hand, when interacting with an ExFJ, comparatively you get a stronger sense of how externally aware they are - usually external social awareness - more than anything else. Of course, this doesn't mean "socially competent" (although the average ExFJ is likely to have the most socially competent people), but the mere aspect of focusing outwardly, judging first by any ethical implications around them.
ExTP and ExFP, and tertiary/auxiliary judging functions
When it comes to ExTPs and ExFPs, it can often be tricky in choosing whether they're one or the other (F vs. T.) Sometimes it may feel obvious, but I think the most important thing is to compare if they're aux Ti/tert Fe, or aux Fi/tert Te. An ENTP (I would say looping, but I think an average ENTP is prone to this too) may look like an ENFP by how "random" and enthusiastic they are. However, because of an ENTP's tertiary Fe, it's likely that they're doing this on purpose - that they want to get a rise out of people, that they are desperate for attention (however buried down it may be). An ENTP is aggressive in this.
And it's not to say that ENTPs are rude and ENFPs are sensitive. It's intention. Despite the Fe doing things for/around people, because the Fe is tertiary, the ENTP struggles more with being socially aware - that is, recognizing that what they're saying/doing works, how people react to what they're doing, thinking about how what they do/say impacts others. The tertiary Fe tries extremely hard to be used, but unlike the ExFJ, the average/unhealthy tert Fe lacks the subsequent awareness in being used.
But the tertiary Fe does not come in just forms of calls of attention - it can come out through complete apathy, in which the user convinces themselves that they don't need
to be concerned with how they affect others; or caretaking, in which the user tries very hard to protect and provide for people around them. Again, though they may behave these ways, the downside of any
tertiary function is consequential awareness.
And like any F in any type, the tertiary Fe is highly selective and protective of those they care about.
The auxiliary Fi is different. People tend to assume that hyper, enthusiastic, random, happy, and usually loud characters are ExFPs, ENFPs more (if the character is ubiquitously happy.) And they're not always wrong.
(I will write a post on dom Se vs dom Ne at some point - that's another distinction I want to discuss.)
However, what sets the loud ExFP apart from the loud ExTP is that there is more... sincerity. (Sorry looping ExTPs.) An ExFP is behaving as such because that's themselves, they're choosing to do so because they want to. Where the obnoxious ExTP is prone to feel more performative or doesn't regularly appear to have some strong internal value driving them, the obnoxious ExFP is just Like That.
Like everyone who knows cognitive functions knows, Fi is largely based on internal self-awareness and personal values/ethics. When it comes to being in the auxiliary (or inferior) function, it is less used and more of a backdrop. What the ExFP and the ExTP have in common is that they are both aware of how they want to affect other people. However, the ExFP uses their (objective) tertiary Te to exert whatever it is they are exerting (usually activities/projects/ideas), while their auxiliary Fi a) knows how they want to affect people, and b) is aware
of how they affect people, due to being in a "thinking/internal" (aux/inf) position.
It's not to say that auxiliary Fi is superior to tertiary Fe. An ExFP may be more naturally likable than an ExTP (your mileage may vary, of course; I'm just going by general overviews), but once the ExTP utilizes their Ti enough along
with their Fe, they will notice patterns and make logical conclusions of how people will react and can easily navigate their way through a social atmosphere. Conversely, a looping ExFP may ignore personal values and their aux Fi will instead depend on external values/situations rather than self-generated emotions, ideas, and principles.
A looping ExFP is unique in that they tend not to look like their more average counterparts at all
. Of course, I can say this about any type - but I feel like, for example, with an ISFJ, you still get some sort of idea that they are an ISFJ despite their being in an Si-Ti loop.* However, a looping ExFP tends to look extremely apathetic, indulging themselves in something they externally act on that they know will not guarantee in making them happy. This is the tertiary Te - usually a looping ExFP is overindulging in creating and performing objectives that their Fi does not genuinely and fully want without some sort of unhealthy motivation. Due to whatever is buried deep down within their auxiliary Fi - whether it's insecurity, trauma, need for attention - that is what's driving them. A looping ExFP knows exactly what
they're doing! They also likely know why but try to ignore that reality. And yet, when presented with an issue, situation, or person they care about, they can easily access those emotions internally because their auxiliary Fi is still auxiliary Fi.
(I've been obsessed with the Good Place recently and there is a certain character there who I keep seeing typed as a T when I am pretty sure it is a looping auxiliary Fi.)
I dislike calling auxiliary Fi users "sensitive," although that's what they are in a more literal sense. Their static Fi both knows who they are and how what they do may impact others. An ENFP who gets into an argument knows
they are, and knows
they will get a rise out of the other person. An ENTP who gets into an argument is either completely unaware, or doesn't care.
So the ability to blatantly ignore that auxiliary function comes with any other type. The thing with ExFPs is that since Fi is basically self-sincerity, ignoring that tends to make them look not like themselves - that is, not like an ExFP and prone to getting mistyped. This is the issue with perhaps bizarre looking extroverts looking like another type... but not quite.
... I absolutely did not mean to make the ExFP vs ExTP portion so long, apologies.* Loops are not void of the auxiliary function, but rather become extremely subconscious while the user struggles with their dominant & tertiary functions. Despite not being "used", from an outsider's perspective they can still be pretty visible.