Comparing the Look-alikes: INTP vs. ISTP vs. INTJ

The INTJ, INTP and ISTP types have often been called “look-alike” personalities. I personally think that that’s in part due to mistypes… In day-to-day life, INTJs and INTPs come across very differently in my experience. There are certain scenarios in which an ISTP will appear similar to an INTJ, but those two as a whole are very different as well. So, I’m going to write up some general comparisons to clarify these three types, and point out some of the indicators that I look for. It may seem somewhat scattered since every section will probably reference a previous section and build on each other as I compare and contrast the types, so you’ll have to read the entire thing to get a complete picture.

Extraverted Intuition vs. Introverted Intuition

Let me start this off by contrasting Extraverted Intuition (Ne) and Introverted Intuition (Ni). To clarify, an INTP’s function stack is Ti-Ne-Si-Fe,  so they are Ne users. On the other hand, an INTJ’s function stack is Ni-Te-Fi-Se and an ISTP’s stack is Ti-Se-Ni-Fe. Note that both of these types are Ni users. Obviously, Ni in an INTJ will be much much stronger than Ni in an ISTP, but there will still be some basic qualities that they share.

Ne users focus on possibilities, so they tend to get really excited when they hear about something new. They tend to be good at brainstorming because they naturally generate ideas and see potential. They sometimes struggle with narrowing their options down to the best one, because they see so many. They enjoy theoretical speculation and what-if scenarios. INTPs are specifically known for being the inventor type – although that is a stereotype though so take it with a grain of salt. However, I did know an INTP who would randomly come up with ideas for household gadgets… and then look very disappointed when he found out that someone had already invented it.

Ni is not like that. Ni focuses more on perspectives so it can discover an underlying pattern or truth, a principle per say. Ni users don’t necessarily want options – They want to know the best path forward. Ni users are likely to get frustrated by Ne users who are constantly throwing out possibilities and hypotheticals since they will view these as excessive and distracting. Ni is prone to jumping to conclusions, which is why they’re known for having a tunnel vision issue. Ni users are known for having that eureka moment – because the answer or solution or insightful observation just kind of pops into their head. So, they’ll just know, without knowing why or how they know. (It’s not magical though – it’s fully explainable, and the Ni “answer” can be wrong.) As a tertiary Ni user, I’ve observed myself leaping to a conclusion, and then having to logically work backwards to rationalize why that conclusion makes sense. An Ni dominant is more likely to just trust that initial instinct.

Conversations

When healthy, INTPs are usually more talkative than both the ISTP and INTJ. This is due to high Ne. When they get started on a subject that interests them, they usually have a lot to say. INTPs tend to explain things in a more roundabout way, feeling the need to share the entire context of something (Si), possibly before actually stating the point of what they’re saying or the conclusion that they have drawn. I’ve even seen INTPs actually completely forget to share the point of what they were saying. As mentioned above, Ne is known for idea generation, so INTPs are good at brainstorming and coming up with endless ideas, theories, speculations, what-if scenarios, and etc. I’ve noticed that high Ne users tend to enjoy puns and word play, due to their natural ability to connect things in an odd and quirky fashion. They make connections to seemingly unconnected things. This is why conversations with them can appear kind of scattered, especially for those who can’t naturally track their train of thought.

In conversations, ISTPs will be more direct and to the point, since they have Se/Ni. ISTPs tend to be known for talking less, but this tends to be because ISTPs struggle to verbalize their thoughts due to the Ti-Ni combo. INTPs may think they struggle with this, but they’ll probably still manage to produce an abundance of words in their attempt to explain something accurately. For INTPs, it’ll be more of an issue with nailing down the precise verbiage that they want. Whereas, ISTPs, who are having to vocalize something that they have not had to vocalize before will probably struggle to find words at all. Due to this struggle, they frequently refuse to try at all. (I personally tend to resort to pointing, gestures, and saying “the thing” or other unspecific words.) ISTPs, if at all possible, are going to prefer to demonstrate their knowledge, rather than verbalizing it. Although, an ISTP can learn how to explain their knowledge and thoughts via practice. As an ISTP myself, if I think about something for long enough and essentially rehearse it in my head, I can usually produce that later on when prompted. However, if you put me on the spot by asking me something I’ve never thought about before and never had to vocalize, I’m pretty much doomed to stutter or give you a blank expression.

A general note about Ti: All high Ti users tend to avoid absolute terminology, which in the context of this article applies to the INTPs and the ISTPs. These types tend to use words like ‘probably,’ ‘maybe,’, ‘possibly,’ ‘usually,’ frequently,’ ‘tend to,’ and etcetera to make everything they say be less absolute and subject to change. You can probably see me doing that in this article… or any of my articles, really. In fact, I always have to go back and delete a bunch of qualifiers because frankly, it gets ridiculous. Nothing about personality theory is absolute anyway, so I’d hate to accidentally box someone in.

Te, in comparison to Ti, is very absolute in nature. AKA: “This equals this. No exceptions.” Ergo, INTJs are blunt, absolute, and to the point. Unlike the IXTPs, they do NOT struggle to state certainties. INTJs will view the world in a more black-and-white way. If it’s wrong, it’s wrong. If it’s right, it’s right. If you disagree with the INTJ, you’re wrong. This mentality should surface in the way that they talk. That’s not to say that they’ll always be mean, but they probably won’t struggle to state an opinion that’s in contradiction to your own, and aren’t likely to feel compelled to sugarcoat their disagreement, due to lack of Fe. Their Te will drive them to state things in the most succinct way possible. INTJs are also prone to stating conclusions and opinions as facts, and may not volunteer their reasoning behind them. They may also struggle to verbalize their thoughts due to Ni, and therefore may be hesitant to try to share their thought process with you. I’ve noticed that the NTJs like to emphasize getting to the point of whatever you are saying, and are less interested in all of the details. They want the big picture, and may talk about perspectives or seek out other perspectives in an attempt to find that big picture. Remember, they’re focusing on principles not possibilities. They may use grand scale metaphors to explain the essence of something. I’ve literally heard the stereotypical “life is like a grand game of chess” type line come from the mouth of an INTJ.

Lifestyle

INTPs tend to be scattered and more on the spontaneous side of life, having less of a need for a concrete plan or advance notice. An INTP that is in touch with their Si may schedule certain aspects of their lives and adhere strictly to those small routines. However, an INTP as a whole will have a relatively loose and flexible lifestyle. They’ll also tend to enjoy exploring new subjects and jumping between hobbies or interests. They’ll get bored with focusing on one specific thing for too long.

ISTPs are also going to be scattered and spontaneous, not needing much advance notice or preparation before going out to do something. They’ll also probably dabble in a bunch of different hobbies. Since they lack Si,  they’re unlikely to adhere to any specific schedule for long, and may randomly switch things up for no apparent reason. (Or simply forget the order that they typically do things in because it just doesn’t matter to them.)

Now, for the INTJs. INTJs probably view INTPs and ISTPs as scattered disasters. INTJs are not typically spontaneous. They prefer to have a plan, and they prefer advance notice before altering their schedule. They’ll be more concerned with their physical environment. That doesn’t mean that they have to be neat freaks, but they’ll want order, and they won’t want you too mess with their order.

Information Gathering/Goals

INTPs won’t need a specific reason to be exploring what they are exploring. If it’s interesting, that’ll be reason enough, or maybe they’ll fall down the rabbit hole of YouTube and end up exploring a subject that they had absolutely no previous interest in. This is a general Ne/Si tendency. Due to their Si, INTPs tend to know random facts about random things due to the random subjects that they briefly took interest in.

ISTPs will usually have more of a concrete reason for anything that they decide to learn. That doesn’t mean it has to be physical in nature; it simply means that they will need to visualize an achievable end goal (Ni) in order to motivate themselves. Otherwise, they’ll see the effort as pointless. INTPs won’t need a goal; they’ll just explore for the fun of it and may or may not find a use for whatever they learn later. ISTPs probably won’t be able to do that. They’ll need goals and reasons. They will see a need and resolve it.
(Don’t fall for the lie that ISTPs are always risk-taking adrenaline junkies. Ti is abstract and attributes of Ti are often misattributed to Ne, causing the average MBTI ISTP description to be too Se heavy. As a result, many ISTPs relate better with the INTP descriptions)

INTJs tend to be good at setting goals and achieving them, due to Ni-Te. Ni makes them focus on one thing, Se gives them the desire to put it into action, and Te will give them the drive to see the end result or the completion of that goal. Te tends to be ambitious and more concerned with the end result, rather than the process. The Se in ISTPs can sometimes mimic Te because Se will motivate them to get concrete results. However, ISTPs are still more likely to enjoy the process more so than the end result. And then comparing that to the INTP… Well, INTPs are known for failing to make their goals/ideas reality because once they’ve figured it out or fully explored it in their head (conceptually), they get bored, and then struggle to find the drive to complete the goal (lack of Te AND Se). I’m phrasing it this way because that does not make them innately lazy, so if you’re using your laziness to claim Ne/Si, you’re out of line. They’re just motivated differently, and will need to learn how to follow through so they can share their ideas with the world.

Insensitivity/Emotions In All Three Types

All of these three types will likely be somewhat blunt and insensitive. That’s just the nature of being a thinker – in our healthy state we still struggle with taking emotions into account before speaking or acting. (That’s not an excuse, by the way. Just a fact. We have to learn sensitivity.) However, INTJs will be instinctively concerned with their own emotions, and oblivious to the external emotional environment. (Unless they run across a situation that they have personally experience, and thus are able to empathize.) This means that INTJs will have a tendency toward unapologetic insensitivity. They said it, that’s what they think, and they just don’t care what anyone else thinks. Tertiary Fi usually makes them very sure of themselves. “I am what I am. You can’t change me.” However, with all that being said, they can be very kind and empathetic people, especially to close friends and family. I’m not trying to say otherwise, but these are just the tendencies that they’re going to have. If they try to help you out and solve your problems, they may try to do so in a way that they think is best or would want (Fi), versus recognizing what you actually want (Fe).

The IXTPs, however, with their inferior Fe will be sensitive to the emotional environment. They’ll probably attempt to read the emotional environment, struggle to do so, and then feel inadequate. They’ll make an insensitive statement by accident and likely feel instant regret as they notice the reaction or response of the affected person (or realize the implications of what they just said.) That tendency may cause them to have an underlying fear of hurting or dealing with others – since they have that Fe awareness but lack the confidence or capability to use Fe effectively. They are going to be more insecure about their ability to navigate a social environment than they let on. (For more info: Inferior Fe from the Mind of an ISTP).

High Ti vs. High Ni

I’m injecting this section into this article real quick (post-publication) because I’ve noticed people subconsciously mix these two functions up. However, I’m not going to cover this topic specifically in this article, and instead will point you to an article Ryan wrote that was completely dedicated to this subject: Ti vs Ni: Am I an NJ or a TP?

Some closing notes…

INTJs don’t typically mistake themselves as INTPs. ISTPs frequently mistake themselves as INTPS, and both the ISTPs and INTPs frequently mistake themselves for INTJs. Ti overthinks everything, so bear that in mind. I could probably have kept on talking about these three types, but I think the article has gotten a little long, so I’m cutting myself off. I hope this article made sense and you found it at least somewhat helpful.