ISTJ
The everyday you
As an ISTJ, you know how it has been done and you do it that way, thoroughly, whatever the distractions. You decide logically what should be done and work toward it. You keep your own values private and firm. And your weakest habit, the one that unsettles you fastest, is seeing what could be, the new and the untested.
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The four selves

comparing with what's been Si · making it work Te · staying true Fi · seeing what could be Ne
At your best you are the person everyone relies on: practical, accurate, responsible, with a well-organized library of remembered detail and proven method. The cost is rigidity. Anything frivolous, disorganized, or needlessly risky puts you on edge, and tending to yourself, or to a change that is coming anyway, is easily overlooked.


seeing what could be Ne · staying true Fi · making it work Te · comparing with what's been Si
You admire the person who sees life as full of possibilities and moves on them with a confidence you cannot account for. That imaginative openness is your weakest habit turned into her strength, so it fascinates you and it unsettles you. You grow toward it by trying one untested thing, on purpose, in a small safe dose.

noticing what's here Se · making it make sense Ti · tending the room Fe · sensing where it's going Ni
Under stress you catastrophize: every disaster that could happen, all of them at once. You lose your usual grip on the facts, act on impulse in ways quite unlike you, and judge yourself harshly afterward. That is your Unconscious, your four habits turned the other way. It is also why someone who lives entirely in the moment can be hard for you to stand.

sensing where it's going Ni · tending the room Fe · making it make sense Ti · noticing what's here Se
When you are watched you play the wise one: quietly sure of where things are heading, attentive to what everyone feels, organized around the common good. You can hold it for a family crisis. Held longer it costs you, because it runs on the habits you own least, and it asks you to trust a hunch over a record.
one type, four selves:
across = reversed · down = turned
NorthYour family
An ISTJ’s four selves are ISTJ, ENFP, ESTP, and INFJ. Those four types share one set of selves, which makes them a family, and every one of the sixteen types belongs to one of four families. That is why your other three are the same as every other ISTJ’s, and why they can be compared with anyone’s. ISTJ is in the North family.
The types most often mistaken for yours
| Your type, or its neighbor | The question that separates them |
|---|---|
| ISTJ or ISTP | One letter, zero shared functions. Do you lead with stored experience and procedure, or with in-the-moment analysis of how things work? |
| ISTJ or ESTJ | Same functions, different attitudes and lead: does the remembered standard lead (Si) or the outward organizing (Te)? |
A detail worth knowing: for introverts, the last letter describes the second function, not the first. Your lead function works on the inside; what the world sees is the second. That is why the types below can look alike from the outside and feel completely different from within.
The workbook
Go deeper, on paper. A workbook for your type, with a chapter for each of your four selves and questions about your own week rather than your traits. It comes as a PDF to print at home, or to fill in on a tablet with a stylus.
The workbook for your type. Fifty-five pages, a chapter for each self, mostly questions to write about.
$14 · PDF Coming soon
Your four selves, as a signature
Your type, and the three that come with it, on one card. Save it, post it, or send it to someone who should take the quiz.
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