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ISTJ is an Introverted Sensing Type. (Another Introverted Sensing Type: ISFJ)

Common traits of Introverted Sensing Types, summarized in Gifts Differing are:

  • Are systematic, painstaking, and thorough
  • Carry responsibility especially well, but ISTJ generally likes it better than ISFJ 
  • Are very hard working; they are the most practical of the introvert types
  • Are outwardly matter-of-fact, inwardly entertained by extremely individual reactions to their sense impressions
  • Are conspicuous for patient and willing application to detail
  • Make an excellent adaptation to routine
  • Absorb and enjoy using an immense number of facts

(Myers et al., 2002)

ISTJ: Introverted Sensing Supported by Thinking

ISTJs emphasize logic, analysis, and decisiveness. With enough extraversion, ISTJs make able executives. They also make exhaustively thorough lawyers who take nothing for granted and thus catch many slips and oversights that others make. All contracts should be cleared by IST]s; they will overlook nothing that is in it and assume nothing that is not.

This is a fine type for accountants. It also appears to be ideal for dictating-machine transcribers. The head of a central transcription department selected three operators as having the perfect temperament for the work; they were chosen for their accuracy, continuity, concentra- tion, and ability to be content without socializing at work. All three were well-marked ISTJ women, though apparently only about one woman in twenty-three belongs to this type.

ISTJs will give any amount of help if they can see that it is needed, but their logic rebels against requirements or expectation to do anything that doesn't make sense to them. Usually they have difficulty under- standing needs that differ widely from their own. But once they are convinced that something matters a great deal to a given person, the need becomes a fact worthy of respect; they may go to generous lengths to help satisfy it, although they still hold that it doesn't make sense. In fact, they may be sharply critical of the carelessness or lack of foresight by which some unfortunate has landed in trouble and, all the same, spend much time and energy to help.

Sometimes ISTJs carry their type development beyond their domi- nant and auxiliary processes and achieve a marked supplementary development of their third-best process, feeling, for use in human relationships, especially for appreciating their closest friends.
(Myers et al., 2002)

ISTJ by Michael Pierce

ISTJs have been commonly nicknamed the “inspectors” or sometimes the “duty fulfillers,” given the stereotype in the Jungian community, as far as I have seen, of a rather boring worker bee satisfied to meticulously “inspect” and maintain all the boring detailed systems underlying society – in essence, an unambitious and short-sighted INTJ. This stereotype is far enough from the truth that the majority of people who get ISTJ on the MBTI test report that they don’t relate to their type description. ISTJ preferences merit far greater appreciation and respect than the nickname “inspector” produces.

As with all of these pieces, I aim to describe the core of the ISTJ profile and the typical ISTJ as an individual just as capable or incapable of becoming a hero of the history books as any other personality.

To begin, let’s break down what constitutes the ISTJ functionally.

They are a Judging type, meaning that they prefer extroverted judging and introverted perceiving. This means that they base their judgment criteria on objective, outside information, while simply observing and drinking in their subjective information and experiences. You could say that they are more aggressive towards the outside world and more receptive towards their inner experience.

Their preferred way of doing this is through extroverted thinking and introverted sensation. Extroverted thinking is inductive. It forms conclusions based on objective data, which they then aggressively try to fulfill. Meanwhile, introverted sensation perceives reality as it is, but invests its perceptions with subjectivity and recalls these subjective memories in similar situations. It is recording, or if you like, cataloguing or recalling.

Third, they are very similar to the ESTJ; both prefer Te and Si. The ISTJ, however, prefers Si more than Te. Nevertheless, they are in some sense the same type, or at least sister types. I personally like to call STJ types the “Scientists”, because they thoroughly examine reality and compare it with all the past experiences they’ve collected in their database. They then form logical conclusions from this breadth of objective data. Of course, “Scientist” is merely a nickname to help me remember the STJ nature and does not mean STJs are more likely to have an interest in actual science.

The ISTJ, then, is a “scientist” for whom their subjective perceptions of reality hold more importance than objective data and its resultant conclusions. They are more concerned with recording and exploring information gleaned from reality than with fulfilling its obligations.

The word I like to use for the ISTJ is “solidifying”, with a very specific meaning attached to it. I have found that part of the principal driving force behind ISTJs is preparation for the future. With the ISTJ there is a sense that the world is unpredictable, ever-changing, and therefore unreliable. To counter this, the ISTJ’s Te collects masses of solid facts to determine with as much certainty as possible what is real and substantive, what is really going to come out on top in the future, and what really happened in the past. So when I say the ISTJ is “solidifying”, I mean they are seeking to find and factually bolster those things they deem real and of actual value and not just another passing fad in this crazy, irrational society of ours.

We can now see where the nickname “inspector” comes from: the ISTJ is notoriously thorough and meticulous. In some sense, they perceive the world as a maelstrom of nonsense and irrationality, and anything that they plan to do has to be constructed to withstand that storm, patiently waterproofing every inch of it and mathematically bolstering every inch of its structure as needed. Anything that they believe in must be submitted to meticulous testing and research to determine if it will serve reliably as they venture into the storm of the future.

Their intense scrutiny gives them another well-known characteristic which is being dutiful. This is because if they are putting their trust in anything it is because their trained eyes have deemed it safe to sail in, and there is no reason they ought not remain loyal to it even when it seems about to fall apart. They knew at the beginning that it would pull through, and no moment of terror will budge their original plan until they are up to their neck in water. Their dutifulness and loyalty extends in how they advise others. If others want to survive the storm, they need to determine what is reliable and then hold to it with courageous fidelity, and ISTJs are saddened or perturbed by how little effort others seem to put into their work and research.

There is another layer to their dutifulness, namely their tertiary Fi. As Sigmund Freud once said, “If I love someone, they must deserve it.” For the ISTJ, once something or someone has passed inspection, their feeling, sentiment and passion will grow deep and rooted within them, and though not deliberately or actively expressed outward, it is powerful and individual. They deeply love what they love, and it no longer becomes just a matter of logical obligation, but of sentimental attachment to those duties that merit this place in their heart. In other words, yes, there is a soft, fuzzy, boiling, passionate, sincere realm in their hearts.

The weight of their introverted sensation, which is responsible for their meticulousness and distrust of the unknown future, crushes their inferior Ne, which would be responsible for the perception and embracing of new possibilities. They recoil from the new and subject it to severe inspection and research, and if too much weight is given to this Si tendency, then the ISTJ can become overly stubborn and resistant to change and ingenuity. AKA the old man who complains about all this unreliable new-fangled junk like the internet and pockets, wishing we could go back to the good old familiar and tested days of radio and togas.

So, in summary, the ISTJ is solidifying, thoroughly determining the reliability of things in patient preparation for the unpredictable future through factual and practical research. However, they do become sentimentally attached to some of their most reliable things, giving them a loving loyalty. Unfortunately, their mistrust of the future can make it difficult for them to accept change and ingenuity without vigorous inspection.

Thanks for reading, and for all the ISTJs out there: thanks for trying to keep things real and reliable and lead us confidently into the future.

(by Michael Pierce)


Myers, I. B., & Myers, P. B. (2002). Descriptions of the Sixteen Types. In Gifts differing: Understanding personality type (pp. 83–114). essay, Davies-Black Pub.

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