mbti | Basic MBTI Functions

Before I get into explaining each of the individual functions, here is the foundation of both the functions and MBTI in general.

Each personality type, as we know, goes in the order of this:

Either I or E
Either N or S
Either T or F
Either J or P

However, when it comes to the functions, we have to forget about the first bulletpoint and the last bulletpoint, at least for a second. They do mean things eventually, but as the Functions (which I will now be capitalizing) basically lay the groundwork for MBTI, and neither IEJP are technically within these functions as we will be initially understanding them, we have to forget about them completely. Just focus on the middle two possible letters - NS/TF.

So. Here we are, with I(N)tuition, (S)ensing, (T)hinking, and (F)eeling. These are basically the four key ways that the brain functions, according to personality typing ideology.

What most people are familiar with is that you’re either N or S, or you’re either F or T. This is wrong. I mean, okay, yes, an ISTJ and ISFJ are valid personality types and they are very different types of people. But that’s not to say that the ISTJ doesn’t have Feeling, or the ISFJ doesn’t have Thinking. To be a mythbuster here, the other core part of MBTI is that everyone has all of these functions. An ISTJ also has Intuition and Feeling; an ENFP also has Sensing and Thinking. And explaining that we have to understand two additional features of MBTI.

The first: So we’ve established the four basic functions, I(N)tuition, (S)ensing, (T)hinking, and (F)eeling.

And now we’re bringing back the concepts of Introversion and Extraversion (i/e).

Here’s what you need to understand: while there are these four basic functions, there are actually two types of each basic function, Introverted and Extraverted. So, eight actual functions in total. These are the ones I’ll be explaining shortly.

It’s also important to note that each function plays a direct opposite to another function, but in the way that if you have one function, you also have to have its opposite. Balance and all that.

The second: And while everyone has different types of each function - that is, if Introverted Feeling is one of your functions, then Extraverted Feeling won’t be - it’s also important to note that MBTI functions work like a “stack” - or rather, they’re not equal, but that for each personality, there is a dominant one, an auxiliary one (these two are the main ones that are found in the personality lettering), a tertiary one, and an inferior one. Or: every personality type is essentially made up of two “Strong” functions, one “Uncontrollable” function, and one “Inferior” one.

It’s hard to define these adjectives more concretely, as generally they can manifest in different ways for different people. The easiest to define but the most difficult to locate and settle on are actually the Strong functions - more specifically, the Dominant one, which people use so instinctively and naturally that sometimes they don’t really think or consider it to be a part of their personality. But anyway - a “Strong” function basically means it’s used with instinct, nature, and subconsciousness - one of the core ways that your brain wants to, and does, function.

With the tertiary function (position 3) and the inferior function (position 4 - can be recognized as the “weak” or “stress” or “stagnant” or “insecure” function, but again, varies from person to person, and personality type to personality type) - these are a lot harder to conclusively explain, but that’s more into personality theory and we’re just talking about functions right now.

MBTI FUNCTIONS

Since I explained earlier that each function also serves to balance another, I’ll be explaining each of these in their pairs. Additionally, all of these functions as explained here exist in a vacuum, unrelated to social justice or personal experiences, as personality types are never indicative of politics or relationships/preferences/experiences/etc.

I’m also only explaining each of the functions only in their dominant position because while I know it’s not the easiest way to figure out if it’s your dominant function (since, as previously explained, we use our dominant functions so naturally that we just often forget to pinpoint them or don’t even notice them), it’s still the easiest way to understand the function at its forefront.

Perceiving Functions, AKA Functions that allow you to take in information, AKA rational functions

1A: Extraverted Intuition (Ne)

Ne says: “What are the possibilities? What if [this likely improbable/impossible] happened?” Ne can be seen as randomness or spontaneity or openminded-ness. Or change!

In balancing the seemingly rigid Si, the Ne opens the mind to the possibilities of the present. Where constant and effective structure identifies the Si, the Ne is the freedom and complete lack of structure away from that. Ne embraces possibilities and probabilities and the endlessness of both the present, but also the future. Ne is generally what people think of when they think of "extraversion" due to the outward energy the Ne loves to absorb and throw back into the world. (This can also apply to Se, but that's in a more physical sense.) Ne loves to learn and question and see, in a very mental manner.

The Ne-dom is incredibly abstract, but outwardly so. Ne-doms tend to talk a lot, even if they say that they don’t like to or don’t see themselves as extraverted as others may do. It’s just that the Ne-dom is bursting with so many ideas, and they also want to hear other people’s ideas, so sometimes they express theirs to get the ideas out of other people. Ne-doms love gathering ideas, whether they’re possible or not, rational or not, because they’re fascinated by the abstract world. To them, today is huge and endless with basically everything ever, no matter how unrealistic or senseless. The Ne-dom will embrace it.

Dominant in: ENFP, ENTP

1B: Introverted Sensing (Si)

Si says: “What do I already know? What has already happened?” Si is commonly associated with tradition, memory, and old methods, whether it’s learning from them or recognizing a comfort zone or wanting to return to an old interest or being nostalgic - and these past things help Si-users also determine the future and what to do now.

It balances the Ne because while the Ne is, in some sense, ‘liberal’ in the present sense, the Si brings the Ne/Si user to structure and familiarity outside of uninhibited possibility. The Si says - the world is full of possibilities, yes, but there is also a way that things may go and things that need to be done, and they should be acknowledged and focused on.

The dominant Si is often focused on trying to organize and execute in the most effective way possible, which often results (though not strictly) in usage of past experiences - an established framework to build the system upon - and/or memory-reliance, because the most efficient way to work is to work with what’s already there. The Si-dom immediately and naturally perceives what they see to be the most usable and workable way at once, and more often than not go forth with it without thinking too much about it. Beyond work ethic, it can also reflect how an Si-dom works their priorities and values - they use the perception they already have and have established to continuously apply it.

The main takeaway from Si is that it is not only structural, but comfortable.

(This can lead to Si-doms to doing things that they know will work because it’s worked for them before, and wanting to live in the world that they think the world is, based on old ideas and the world they’re used to having always lived in. But Si being attached to ‘traditional values’ and ‘good planners’ tends to be a senseless correlation, as it’s not the value but rather the method that identifies the Si.)

Dominant in: ISTJ, ISFJ

2A: Extraverted Sensing (Se)

Se says: “Where am I right now? How am I presently interacting with the world?” Se is concrete, the physical (though not necessarily bodily) present, experience existing just as it is - every moment we are here is experience.

Balancing the Ni, the Se brings the Se/Ni user into the existing world around them, instead of an abstract internalization only happening in their head. It is actually the most literal definition of “grounding” (though the Ni is more anticipatory than dreamy), because it fundamentally has to do with the concrete workings of right now. The Se can be excited and spontaneous and all over the place; Se can also be chill, but very much present. Se is externalization and outside of one's head, instead in touch with their physicality and the world around them.

Due to this, Se-doms tend to be interested in sports, risk-taking, traveling, fashion, or other things that have to do with doing and working, especially to do a new task or of interest. Se-doms are very much hands-on, live for experience, and constantly in the moment - while they can be as talkative as an Ne-dom or as efficient as a Te-dom, they primarily know how to live now - and that can be a good thing. (That can also be a bad thing - no function in any position is inherently superior or inferior to another.) They live on the outside - not necessarily outgoingness, but with the mental focus on the things happening physically around them, than within. They notice what is happening around them and live in action and reaction.

Dominant in: ESFP, ESTP

2B: Introverted Intuition (Ni)

Ni says: “What will happen? What do I want to happen?” Ni is often regarded as prophetic or predictive - it can either be knowing how things will happen, or knowing what needs to be done to make certain things happen. More or less, it's pure abstraction in the mind, with a slight predicator what happens next.

Ni balances the Se in rather than letting the Se/Ni user always “live in the moment,” it also deals with the internalization and abstract understanding, leading to goal-setting, ambition, and internalized structure based on pure mental work and understanding. There is no external action here - it is the internal work, things that happen in the mind to follow and further something streamlined.

Ni-doms often see themselves as knowing what will happen before anyone else does, which can be true, anyway. Ni-doms look for symbols and meanings, less in a spiritual/religious way, and more on… finding things mentally, carving a path to do before they start doing the first thing, things that are purely inhibited in the mind because there is a constant need to structure and rework things inside. Ni-doms always find plans for or trust the future, whether it’s an actual plan or advice for someone else, because they always know. At the end of the day, the Ni-dom already understands tomorrow morning. If not, you know, the next week.

Dominant in: INTJ, INFJ

Judging Functions, AKA Functions that allow you to interpret information, AKA irrational functions

3A: Extraverted Feeling (Fe)

Fe says: “What are the feelings of the people around me? What do others need?” Fe is largely seen as sympathetic - which, well, it usually is. And since it’s extraverted, it’s actually taking action based on the work of sympathy, rather than just understanding the feelings of others.

Fe balances the Ti in bringing sympathy to what can be seen as coldness or detachedness (interestingly enough, the ISTJ which is often seen as the ‘coldest’ personality is actually not a Ti/Fe user at all.) Since Ti centers on personal logic with no feelings involved, Fe brings the Ti/Fe user back amongst the people, how they feel and overall social recognition and needs.

Fe in the dominant position is usually seen as caring and helpful, often counseling or teacher-type characters. If they’re leaders, it’s usually for the people, rather than for a goal or some sort (which would be Te.) Fe-doms, of course, can have a strong sense of self, values, and individuality, like an Fi-user - the main thing is, though, Fe-doms will still make the majority of their decisions based on the feelings of needs and others, while their personal feelings still exist. And, of course, their personal feelings can fuse into their Fe - Fe-doms actually often get their opinions and personal values based on feelings of others, either as told/imposed by them, or by how the Fe-dom themselves judges what others need.

Due to their intrinsic connection and understanding with other people, Fe users are also good at making decisions to affect the feelings of other people around them - so far I've worded this as overall a positive thing, but let's not forget that manipulation is also highly dependent on one's ability to understand people. Fe has that constant awareness of other people, which can affect a whole host of things for oneself: their own self-worth (because of other people); their ability to comfort, connect, and sympathize; their ability to understand people to make those people do things; and more. Fe is a masterclass in understanding how interactions and relationships work, and all the ins and outs of emotional resonation - or working towards that, in any case.

Dominant in: ESFJ, ENFJ

3B: Introverted Thinking (Ti)

Ti says: “Where are the patterns? How can this logically be explained?” Ti is fundamentally analytical and seeks rationality (although again it is still considered an 'irrational' function; Ti is simply one’s personal understanding of logic and reason) - everything can be, or should be, explained logically.

Of course, Ti balances the Extraverted Feeling with the “inner voice of reason,” although it's less reason and more of the Ti/Fe user’s understanding of what makes sense to them. The Ti can ground the Ti/Fe user in their personal sense of logic, when paired with sympathy exuded to the world. On its own, the Ti seeks detachment in order to understand everything "objectively," which again is up to the user's understanding of logic. They also seek to explain everything objectively - you might realize at this point I'm a Ti dom.

In the dominant position, Ti users tend to make their judgments based on what they perceive as pure unadulterated logic. They like patterns and tend to be good at finding them, instinctively trying to find logical explanations. Everything they do has “justification,” and the world can do whatever it wants, so as long as the Ti-dom can analyze it from afar. Due to this, however, Ti users tend to be oblivious where their analyses require more context than they have, or if the Ti user themselves is a factor within the situation that they are trying to analyze. Other people - the Ti user's interactions with them especially - tends to be a massive blind spot when such examinations occur.

Ti enjoys logical complexity, to take it apart mentally and put it back together. The more a Ti develops, the more they learn to understand that their idea of logic and reason needs to constantly expand, so that their idea of unadulterated logic does not have gaping holes of simplicity or lack of complex. Of course, the highest form of Ti also realizes that emotions and sympathy can and should be factored into their idea of rationality, too...

Dominant in: INTP, ISTP

4A: Extraverted Thinking (Te)

Te says: “What has to be done? What actions need to be taken?” The concept of Extraverted Thinking probably sounds initially oxymoronic, but it’s basically the physical act of planning, taking action, and commanding.

In balancing the Fi, it allows for the Te/Fi user to see the world as a place where things need to be done, rather than letting the Fi/Te user stay contained within their personal feelings and values and mind. For someone who can have so many feelings or ideals, the Te allows them to also be efficient action-takers. Te can be thought of as "autopilot," except fully conscious - execution of tasks can be difficult for many people for whatever the cause; but largely, Te is the idea of just applying. It is seeing the world as something moldable, and usually going forth and molding it.

Te in the dominant position are usually boss-types: not just those who need to get things done, but also just… get them done. It’s often a sense of duty, or a strong drive, or a goal. This will differ, of course, with various situations; but in most environments, Te-doms are the ones you see effortlessly leading and planning, knowing how to be efficient and effective. Te doms are the ones comfortable making decisions and doing what needs to be done, if either by themselves or with other people.

A common misconception about Te doms being extraverted is that they're, well, extraverted in the conventional sense. Don't misunderstand this - many times they are not necessarily "outgoing," but they are still comfortable enough interacting with other people, if it is what their execution requires (or even not.) Again, to the Te dom, the world is always theirs to act upon and modify at any given time; they are always piloting the plane, even if they don't know where they are going. The Fi gives Te purpose, meaning, and drive - it directs the Te if in terms of values or in the moment. Te would truly just be autopilot without Fi - or if the Te/Fi (or Fi/Te) user is not in a great mental space, really.

Dominant in: ENTJ, ESTJ

4B: Introverted Feeling (Fi)

Fi says: “What do I want? How do I feel about this?” Sometimes people mistake it as selfish - but it’s more about having that sense of who one is, what one wants, and how one feels about things.

I suppose this sounds odd since everyone does feel things and everyone does have values, but for an Fi user who, somehow, exerts their external energy on objective action (Te), they need the subjective reflection to balance that out. Fi is purely yourself, which can either lead to a strong sense of identity or constant identity crises; an inherent understanding of your feelings while not knowing how to put them into words; seeking and developing attachments that are not just a part of you now, but as a part of your identity for a long, long time. Though everyone has passions, feelings, and perhaps a sense of individuality, the Fi inherently (or tries to) understands that they are their own person, and who they are and what they feel comes first, even if they don't understand that themselves.

Again, it is not to say that it's selfish: actually, many Fi users highly value the people around them, so they can often be selfless to a fault. Additionally, if an Fi user values honor, loyalty, respect, courage, and other noble principles, they strive to act on them, which again is entirely unselfish. It's easy to dismiss the Fi as based on purely on the individual's feelings (selfish) or moral values (selfless) when it's both; where the Fi does not have the same type of interpersonal understanding of people as Fe, they have an intrapersonal understanding of themselves and who they are in the world around them.

Fi values uniqueness and individuality to the core. In the dominant position, it's basically always living in a “soul searching” world. Fi knows or subconsciously learns what they like, what they want; they make personal judgments without thinking, based solely on what they know about themselves, their values, and automatically trusting their feelings. Even if they doubt themselves, they absolve to understand themselves and to stay true to that. Fi is often explained simply as individuality, but I think it’s more it’s a constant-running instinctive self-reflection, and seeking to polish, understand, and act on that.

Dominant in: INFP, ISFP

WHAT FUNCTIONS DO ALL THE TYPES HAVE?

ENFP: Ne (dom), Fi (aux), Te (tert), Si (inf)

ENTP: Ne (dom), Ti (aux), Fe (tert), Si (inf)

INFJ: Ni (dom), Fe (aux), Ti (tert), Se (inf)

INTJ: Ni (dom), Te (aux), Fi (tert), Se (inf)

ESFP: Se (dom), Fi (aux), Te (tert), Ni (inf)

ESTP: Se (dom), Ti (aux), Fe (tert), Ni (inf)

ISFJ: Si (dom), Fe (aux), Ti (tert), Ne (inf)

ISTJ: Si (dom), Te (aux), Fi (tert), Ne (inf)

ENFJ: Fe (dom), Ni (aux), Se (tert), Ti (inf)

ESFJ: Fe (dom), Si (aux), Ne (tert), Ti (inf)

INFP: Fi (dom), Ne (aux), Si (tert), Te (inf)

ISFP: Fi (dom), Se (aux), Ni (tert), Te (inf)

ENTJ: Te (dom), Ni (aux), Se (tert), Fi (inf)

ESTJ: Te (dom), Si (aux), Ne (tert), Fi (inf)

INTP: Ti (dom), Ne (aux), Si (tert), Fe (inf)

ISTP: Ti (dom), Se (aux), Ni (tert), Fe (inf)

When together, theoretically I'm sure you can assume what a lot of these functions can bring out in a person. For example, an ENFJ - an Fe dom and Ni auxiliary, is probably extremely good at manipulating people. An INFJ, on the other hand - an Ni dom and an Fe auxiliary - is excellent at giving advice, to the point where it may be overbearing because they're always right. This is usually what leads to more accurate descriptions of each MBTI type on the internet.

Fundamentally, though, I believe that figuring out your MBTI type and what that should mean to you comes with a core understanding of yourself. I'm aware that it's perceived by many to be "astrology for business majors," which I won't necessarily argue against since MBTI can't necessarily be proven or disproven any more than astrology can. (My dominant Ti says otherwise, but I won't get into that.) I personally don't care about the capitalistic application of MBTI and personality; rather, I think that MBTI can be helpful in self-growth and applying yourself in situations that you may not be comfortable in. When you start to see yourself, and oftentimes others, in a way that you haven't been able to see them before, it can allow you to stop assuming the worst of people, and start discovering what you really need to work on. For example, if you're an Si dom it does not mean embrace new ideas and methods blindly, but rather recognize where the Si dom benefits you (which should be in most situations, for yourself), and where it may hinder you that you might need to tap your inferior Ne in, however briefly. No function is inherently superior or inferior; rather, it highly depends on what works for you.

Also I do want to note that while your MBTI type consists of four of the eight functions, it doesn't mean that you're lacking the other four functions entirely. Instead, those other four functions become your "shadow functions," which... I won't really get into here. The point is that MBTI theory states that your brain is more inclined to your four functions in whatever order they are, and the other four aren't invisible, but aren't as relevant to you or your processing of information.

Anyway, do note that MBTI is not just the big picture of each personality, or even each letter, but rather each of these eight core functions. There are a lot of other MBTI theories that I won't get into here (looping, unhealthy, in the grip...), but to understand MBTI at its fundamentals is to understand this post.