Am I an INFP or an ISTJ?

I know what some of you may be thinking right about now. Why would you do a typing dilemma for whether someone is an INFP or ISTJ? Those two types are nothing alike. While on the surface you would be right, there are certain scenarios that can cause the line between them to blur. They do, after all, share all the same cognitive functions. In addition to that, they are both introverted. Honestly, once you get past the stereotypes, there is a decent amount of commonalities between the two. So, let’s delve into some of the similarities and differences, and how to tell them apart.

Why They Can Look Similar

1. They both share the same four cognitive functions

INFP: Fi-Ne-Si-Te
ISTJ: Si-Te-Fi-Ne

As you can see laid out above, the ISTJ and INFP are both dealing with the same set of functions. While typically there are defining traits that highlight an Si or an Fi dominant, this does not mean that they can’t look alike. For instance, these two types can be easily confused when they are really unhealthy/looping, or on the flip side, when they are really balanced. A balanced ISTJ who is in touch with their emotions, for example, could potentially start looking somewhat like an INFP. On the other hand, a balanced INFP, who has a good handle on structuring their life, could potentially start looking like an ISTJ.

2. They are both introverted

Both ISTJs and INFPs lead with an introverted function. This will cause them both to default to observation over action. Both can have a tendency to be overly reserved, which would make them hard to tell apart. The less information that they give you, the harder it will be to distinguish which is which. If you only get the bare minimum out of them, you may recognize an Fi judgement or Si observation, but be unable to distinguish where in the stack those functions lie.

3. They can both try to act more masculine or feminine

An INFP that is trying to act more masculine has a tendency to crutch too hard on their Te. This can lead to them showing much more Te than they would otherwise. At a glance, this may make them look like a thinker, but typically any extended observation will lead one to notice a level of Fi motivation that an ISTJ usually does not possess.

Alternatively, an ISTJ who is attempting to come across as more feminine may crutch on Fi. They will try to skip over their Te to appear softer and more emotionally-engaged. Again, this can, at a glance, make them appear to be a feeler, but if you watch them for long enough, there should be signs that this behavior isn’t their default response.

How To Tell Them Apart

1. Their approach to planning (Si + Te)

While both of these types can produce detailed plans and use lists to keep track of what they need to do, there is still a difference in the way that they go about it. If you are able to observe them for long enough, you will find that INFPs will tend toward leaving things more open-ended. ISTJs, on the other hand, will take a more structured approach with their planning. Basically, what this means is that INFPs will fashion the plan in such a way that improvisation will be possible and welcome. Their plan will allow them to adjust as needed to follow whatever direction things naturally end up going. An ISTJ is going to be less likely to do this. They will tend to have a much more specific plan, which may include multiple contingencies in case something goes awry.

2. Their approach to structure (Te)

This goes hand-in-hand with the previous point. ISTJs, as a whole, will tend toward wanting more structure than the INFPs due to the higher Te in their stack. While they may not consciously assert this desire, it will come across in the way that they do things. They will naturally take a more structured approach to most activities. On the other hand, while INFPs can be structured, they are more likely to take an open-ended approach.

The confusion between INFP and ISTJ on this point can happen if you are observing one specific thing that an INFP has decided to tightly structure or control. This is not uncommon, since inferior functions can outlet very strongly. However, it will usually only be centered around one specific thing (or subset of things) instead of being a general approach to their entire life.

3. Their approach to identity (Fi)

This is one of the main areas where you should be able to distinguish one from the other. Barring a loop situation, an ISTJ should be much more cemented in place when it comes to their Fi identity and morals. Typically, they will not care for dwelling on these things once they have laid the foundation. Once established, ISTJs prefer to not have to come back and re-evaluate their stances on things. The ISTJ that does find themselves obsessively re-evaluating their identity is usually in a loop, which will be addressed later in this article.

This is in stark contrast to the INFP. Fi dominants tend to view their identity and values as much more dynamic. Their identity and values tend to be in a constant state of growth and evolution. It will be much more natural for them to re-evaluate themselves on a semi-regular basis, and to see that as normal behavior.

4. Their approach to speculation (Ne)

Their use of Ne is probably one of the biggest giveaways between the two types when you can identify it. Ne in the ISTJ tends to be pretty weak and as a result, will manifest in fairly insignificant ways and may be hard to see at all. Ne tends to come to ISTJs in random bursts that they often express being unable to control. Typically, their only consistent use of Ne is when coming up with negative scenarios which they feel the need to account for. While ISTJs may occasionally produce a more playful type of Ne speculation, it will typically only be shown to those who are extremely close to them.

INFPs on the other hand, provided they are not in a loop of some sort, tend to use their Ne to do far more speculating than their ISTJ counterpart. They tend to devote more of their energy to thinking about the different possibilities, both positive and negative. This leads them to often come up with several ideas, which they may more readily share with others. It also leads them to leave things more open ended than ISTJs usually do. ISTJs, in comparison, tend to approach things in a more focused and linear way. They prefer to find ways to limit and control possibilities rather than allow them to potentially play out.

5. Their fixation when stuck in a loop

It can be hard at times to distinguish between an Fi-Si loop and a Si-Fi loop. It is here that I would say that most of the confusion exists between the two types. A feedback loop between Fi and Si can make it hard to tell which one is dominant. The best way to distinguish them from one another is to see where the fixation lies. Typically, in a loop, the tertiary function is the fixation point that the dominant function is pouring its energy into. So, an Fi-Si loop would have a greater fixation on the comfort of the past, for example. A Si-Fi loop, on the other hand, would have an Fi fix, which tends to shift the focus onto morality and identity. (Bear in mind, that a healthy INFP may relate somewhat to the ISTJ’s Si-Fi loop, and vice versa, but they will be actually functioning and interacting with the world through their extraverted functions.)

The Fi-Si loop tends to provoke the INFP to relive the emotions of the past. They may focus on all of the guilt, shame, and embarrassment attached to past mistakes, which will drive them to fear any new action. This causes them to want to relive their positive past experiences over and over and never leave their comfort zone.

The Si-Fi loop, on the other hand, tends to provoke the ISTJ to evaluate past actions and start questioning whether they have stayed true to their own identity. They may be plagued with remembering all of the times that they were inconsistent with their values. They may start questioning who they are, and feel as if they are a fraud. They will be frozen in inaction due to distrusting themselves and their motives.

Summary:

So, there you have it. Hopefully this will help with distinguishing the INFP and ISTJ that fall into that murky, in-between area. In the end, INFPs should still present with more Perceiver leaning tendencies, and ISTJs should present with more Judger related ones due to what extraverted function they more naturally prefer. Like most things personality related, close observation and open discussion with others and yourself is usually the most helpful in uncovering the valuable information that you can use to figure things out.