An INTP’s Take on the MBTI

My next thing on Aristotle is coming up; it’s another supplement rather than part of the main series. This time, it’ll be a collection of short arguments for why reductionism can’t fully account for reality. That’ll lead into part 3, which will be about substances and accidents, which will then lead into the formal and final causes. I might also do a Good Friday post this Friday.

But for now, I feel like writing about the MBTI. I always find myself periodically coming back to it, not necessarily because I think it’s true, or even because I find it useful, but because it’s a fun thought game. The catalyst for my latest  case of MBTI mania is the blog, which I discovered a few weeks ago. has tons of character analyses, which were very eye-opening; seeing those was my first time seeing an analysis of personality based on actual MBTI theory rather than the distorted version that most people on the internet use (which is basically the Five Factor Model minus neuroticism). But the section on the theory behind the MBTI is a bit sparse in places, so I just thought I’d make a little summary of how the MBTI works. Besides, I just like writing about systems like this.

The premise behind the MBTI is that there are four basic mental functions:

Thinking (abbreviated T)
Feeling (F)
Sensing (S)
Intuition (N)

(N is used for intuition because I is used for introversion.)

Thinking and feeling are grouped together as “judging” functions, while sensing and intuition are grouped together as “perceiving” functions. Each of these mental functions can be directed inward (“introverted”)  or directed outward (“extraverted”), resulting in 8 different functions+directions. The same function pointing in a different direction can actually turn out looking very different from its other variant, so you might even say that each function+direction pair is its own separate function. The direction of a function is indicated by a lower case e or i after the function abbreviation; so introverted thinking would be Ti, whereas extraverted thinking would be Te.

Everyone uses all four of these functions, but differences in personality arise because different people use the functions with a different inward/outward orientation, and because different people are naturally better at using different functions.

So the 8 functions+directions are:

Introverted thinking (Ti): Making sense of things
Ti-users judge based on what makes sense to them. They often love to learn about how things work. Stereotypically, they’re said to be attracted to abstract subjects like math, but this isn’t always the case by any means; in fact, if I’m right in thinking that my brother is an ISTP, then he would be an example of a Ti-user who hates math. Ti-users often don’t care whether their ideas have any practical applications; they like thinking for its own sake. If they aren’t careful to check their theories against facts, they may end up coming up with all kinds of elaborate systems of rules that do technically generate the proper results, but do so by making use of constructs that have no basis in reality; for numerous examples of this, research linguistics. They are often very precise and careful in their word choices. (This one is my primary function.)

Extraverted thinking (Te): Getting results
Te-users judge based on what gets the best results. They make efficiency a top priority. They tend to be highly organized, and often end up being the ones to plan out events and such. In contrast to Ti-users, who think in terms of what makes sense in their own heads, Te-users’ thought processes are based primarily on empirical evidence, and they tend not to care about ideas unless they have practical applications. They are sometimes overly blunt.

Introverted feeling (Fi): Understanding and acting on one’s own feelings
Fi-users judge based on what feels right to them. This isn’t to say that they don’t sympathize with or care about other people, or that they’re irrational; they just choose their own loyalties rather than letting other people dictate things to them. They generally don’t care much about fitting in with a group, though that’s not to say they necessarily like standing out either. They relate to others primarily on the basis of shared experiences, and may have difficulty sympathizing with people without common experiences.

Extraverted feeling (Fe): Understanding other people’s feelings and relating to groups; charming other people
Fe-users generally judge based on what preserves harmony or what they have learned from others, such as their parents or siblings. In contrast to Fi-users, Fe-users relate to others simply on the basis of being fellow humans. They are more likely to follow social conventions than Fi-users. Since their feeling function is turned outward, they may have an easier time observing other people’s emotions than processing their own. They are often good at charming, inspiring, or persuading people.

Introverted sensing (Si): Past-focused sensing
Si-users constantly compare what they are experiencing now with the past. They often have a good memory, even without using devices like memory castles. (I’m an Si-user, and I write pretty much everything on this blog from mostly-unassisted memory.) They may be prone to nostalgia and to revisiting things that they’ve enjoyed in the past. They often stick to tried-and-true methods for solving problems.

Extraverted sensing (Se): Present-focused sensing
Se-users live in the moment and pay close attention to their surroundings. They are more likely than Si-users to appreciate the “fine” things in life, like good food and aesthetic beauty. (Not that Si-users don’t appreciate those things; Se-users are just more sensitive to them.) Many Se-users gravitate toward sports, dancing, or other intense physical activities.

Introverted intuition (Ni): Centralized focus; eerily accurate gut feelings
Ni seems to me to be the hardest function to describe in one phrase; it seems to have several unrelated traits bundled together. Either that, or I just haven’t figured out what the connecting link is yet. Anyways, Ni-users tend to have a very universal, long-term perspective on everything. They tend to come up with a vision of what they want to do with their lives at a very young age. Once they make a decision, they will devote themselves entirely to it. They also tend to have eerily accurate gut feelings; Arvid Walton of fame describes them as “notorious for knowing things that they’re not supposed to know.”

Extraverted intuition (Ne): Decentralized focus; unconventional thinking, creativity
Ne is responsible for seeing the many different possibilities inherent in any situation. Ne-users tend to draw connections between seemingly unrelated ideas, come up with unconventional solutions to problems, and be highly creative. They also tend to have a hard time focusing on a single task; as soon as they start doing one thing, they come up with another totally awesome idea that they just have to work on right now. Unlike Ni-users, Ne-users actually don’t tend to have accurate gut feelings.

Keep in mind that all the descriptions above are trends, not hard-and-fast rules. Each description also applies primarily to people who use that function as one of their better two functions; the functions will come out differently depending on how good a person is at using it. For example, someone who uses Fe but isn’t naturally good at it may show an excessive need for validation from their chosen social group. Or someone who uses Se but isn’t naturally good at it may be easily overwhelmed by overstimulating situations.

Speaking of which, everyone has a hierarchy of functions. The function you’re best suited to using is called your dominant; second best is called auxiliary; third is tertiary; and fourth is inferior. (So that stuff in the previous paragraph about not being naturally good at a given function refers to having that function as your tertiary or inferior, especially inferior.) The directions of your functions alternate down the hierarchy, so if your dominant function is introverted, then your auxiliary will be extraverted, your tertiary will be introverted, and your inferior will be extraverted. If your dominant is extraverted, then the orientations of your functions will be the opposite: auxiliary introverted, tertiary extraverted, inferior introverted.

Your two judging functions will always have opposite orientations, and likewise with your two perceiving functions. Furthermore, your inferior function will always be of the same judging/perceiving category as your dominant; a judging dominant will have a judging inferior, and a perceiving dominant will have a perceiving inferior. So if your dominant is Ti, then your inferior will be Fe; if your dominant is Ni then your inferior will be Se; if your dominant is Ne then your inferior will be Si; and so on.

Due to all of these constraints, once you know what two of a person’s functions are, you already know what the other two are; and if you know what a person’s four functions are, then once you know the hierarchical position of any one of his functions (the dominant will probably be the most obvious), you can derive the rest of his hierarchy.

For example, the functions that I’m most conscious of using are Ti and Si. (The fact that the two functions I’m most conscious of are both introverted is actually a sign that I’m in what’s called a “function loop.” Which is a bad thing. But more on that later.) So that means that my other two functions have to be Fe and Ne. Let’s suppose my dominant function is Ti, which makes sense given my taste for abstract subjects like math, computer science, and linguistics. Since Ti is a judging function, my inferior would have to be Fe, my other judging function. My auxiliary would then have to be Ne, my other extraverted function, to create the alternating pattern. That leaves Si for my tertiary. So my full hierarchy is Ti, Ne, Si, Fe.

A person’s function hierarchy is what determines his type. Types are indicated by a four-letter abbreviation. The first letter indicates the orientation of that type’s dominant function, I for introverted and E for extraverted. The second indicates the type’s higher perceiving function, N for intuition and S for sensing. The third indicates the type’s higher judging function, T for thinking and F for feeling. The fourth indicates which of the type’s two higher functions is extraverted, J if the judging function is extraverted, P if the perceiving function is extraverted. So my type would be abbreviated INTP: dominant function introverted, intuition higher than sensing, thinking higher than feeling, and perceiving function extraverted.

Incidentally, the fact that I don’t post very often can be blamed on Ne. For one thing, while I’m writing a post, I think about all the things that might be wrong with it and all the extra things I can add, and that makes me put off posting it forever. For another thing, I keep on having ideas for new posts before I finish older ones. This would be my 17th post; I have 18 drafts. 20 if you count the two I thought of just now. And even more if you count the others that I have in text files on my desktop.

EDIT: Well, obviously it’s my fault since I’m the one using the function. But the reason I have that tendency is because of Ne.

Now, about function loops. I mentioned earlier that the functions I’m most conscious of using are Ti and Si. This doesn’t quite seem to fit my type; you’d think that if I’m an INTP, my two most used functions would be Ti and Ne. This is a sign of a condition called a “function loop.” A function loop is when you use two of your functions to the (near-)exclusion of the others. Dominant-tertiary loops are particularly common because, although your auxiliary function is the one you’re second best at using,  the tertiary is often the one that people are second most comfortable using, since it’s oriented in the same direction as the dominant. If a person ends up underusing his auxiliary and over-relying on his tertiary, then he will end up either stuck inside his own head (for introverts), or constantly out and about without ever stopping to introspect (for extraverts). Neither of these situations is healthy. So if you find yourself thinking, “It seems like I don’t fit into any of the MBTI types because both my dominant and my auxiliary are introverted/extraverted,” you’re probably actually in a function loop. In fact, to be perfectly honest, I’m not entirely sure that I’m not an ISFJ; it wouldn’t surprise me if it turned out that Si is actually my dominant. This would also make sense because my Ne often acts like an inferior function, distracting me with all the possible ways things can go wrong. But then my Ne also acts more like a proper auxiliary at least part of the time, especially when I’m listening to music; I always try to think of theories for why a certain melodic phrase sounds good, and while listening to music I often get ideas for pieces that I could compose but which I never end up composing. By contrast, my Fe never really acts like a proper auxiliary; I am not good at charming people or anything. Heck, the fact that I’m even considering the possibility that I’m an ISFJ is probably because of Ne. But anyways…

Another anomalous condition is called being “in the grip.” This is when a person over-relies on his lower two functions and stops using his upper two (hence he’s “in the grip” of his lower functions). The trouble with this is that people are not as good at using their lower functions as their upper functions. For example, an Ni dominant may stop following his overarching vision and find himself indulging in hedonism (Se), or an Si dominant may find himself paralyzed by fear of all the  things that might go wrong with whatever he thinks of doing (Ne). People with Se or Ne higher up in their hierarchy would be able to use these functions in healthier ways because they have better control over them.

And the last anomalous condition that comes to my mind is shadow functions. Although everyone has a set of four functions that they’re best at, they also theoretically have the potential to use the other four functions that don’t appear in their hierarchy, called “shadow functions.” This is not advised because everyone sucks at using their shadow functions. No exceptions. As far as I know, people generally only use their shadow functions after experiencing some kind of trauma.

And that about sums up what I know.

I have some mixed feelings about the MBTI. On the one hand, it seems eerily accurate. I have read some descriptions of introverted sensing that were so relatable to me that they actually made me laugh out loud. Similarly with holistic descriptions of INTP’s. On the other hand, there are some aspects of the system that just don’t quite fit. For one thing, what exactly is intuition? What makes extraverted intuition and introverted intuition variations of the same thing? In what sense is a perceiving function introverted? Is it perceiving something inside the user? But Ni, for example, often picks up on things outside the user, like subtle cues in people’s body language or the like. And before we even consider the internal consistency of the MBTI as a system, it also seems worthy of note that there is absolutely no empirical evidence to support it. Even the aforementioned Arvid Walton admits that there is no evidence for it–but says that you should use it anyway because it works. In any case, it’s fun to analyze fictional characters and try to tweak the arrangement of functions until you’ve figured them out.

A couple of sources (since I’m feeling too lazy to explicitly label everything with a citation. This is a blog post, not a research paper. Even if it sounds more like the latter.):