Jung: the original, and everything after

Jung published Psychologische Typen in 1921, eight years after the break with Freud, and stated plainly what question drove him: how could two incompatible theories — Freud’s, centred on the object and on desire directed outward, and Adler’s, centred on the subject and on power — both seem true to the men who framed them. His conclusion was that the difference lay not in the data but in the habitual direction of each man’s consciousness.

What came out of it does not resemble a personality test. The first nine chapters cross the problem of types in antiquity, in the Church Fathers, in the quarrel between nominalists and realists, in Schiller, in Nietzsche, in Spitteler’s poetry. The descriptions of the eight types occupy chapter X, at the end, and are explicitly presented as extreme portraits — clean cases that barely exist in pure form.

Record that before anything else, because everything after it inherits from here: there is no measurement at the origin. There is an attentive clinician describing what he saw, with enormous erudition and no sample at all. The strength of the text is literary and observational. The weakness is that there is no way for it to be wrong that anyone could demonstrate.

In the original scheme there is one introverted intuitive type. Only one. Whoever’s consciousness is governed by inward-turned intuition belongs to that type, full stop — Jung does not subdivide it by whatever comes second. The INTJ and the INFJ are therefore the same Jungian type, described in the same chapter, in the same words about the mystic and the crank.

The letter that separates the two of you — T or F — is Myers’ way of naming the auxiliary function, inside a rule she created and Jung never formulated. It is not a refinement of the original; it is a theoretical decision laid on top of it. When someone writes “Jung said that the INTJ…”, they are quoting Myers with the wrong name on the cover.

This has a practical consequence any typology forum will confirm: INTJ/INFJ confusion is the commonest and the hardest to resolve. That is neither chance nor carelessness. In Jung’s terms the two share exactly what he considered definitive — the same inward perception, the same certainty without a chain of reasoning, the same difficulty translating it — and differ only in what he never systematised.

In a later essay, gathered into the same volume of the collected works, Jung wrote that the purpose of a psychological typology is not to classify human beings into categories — that, he said, would be fairly pointless. The purpose is to give the clinician a critical apparatus: a way of knowing that his own reading of the patient already arrives bent, and in which direction.

The irony is obvious and worth stating without elegance: the reader most at risk of using type as a label is exactly the one who reads best, retains most and systematises hardest. Which is you. The INTJ has a particular weakness for closed systems that explain people, and the defence against it is not abandoning typology — it is remembering that typology describes a tendency of consciousness rather than issuing a licence.

Jung also insisted that a type is a habitual disposition and not an essence, and that the portraits in chapter X are extreme cases nobody embodies entirely. A century later, with sixteen acronyms sold as identity, that is probably the most useful sentence he left behind.

Katharine Cook Briggs had been sketching a typology of her own at home, out of biographies and the people around her, when she read the English translation of Psychological Types, published in 1923. She recognised a better system than hers and adopted Jung’s. Her daughter, Isabel Briggs Myers, a political science graduate, began in the early 1940s to turn that descriptive scheme into something a person could answer on paper.

Neither of them had training in psychology. Her biographer Frances Saunders records that Myers learned item writing and test statistics as an apprentice to Edward Hay, personnel manager at a Philadelphia bank — not in a university department but in a human resources office. The motive was wartime: with millions of women entering factories and offices for the first time, Myers wanted an instrument that would help each person find a post compatible with the way she actually worked. The first form of the indicator circulated around 1943.

That is worth weighing without contempt and without indulgence, because both easy readings get it wrong. Two brilliant laywomen built, outside the university, the most widely administered type instrument in the world; academic psychology only examined it closely decades later, and the reviews it produced are predominantly critical. The part that concerns you is a different one: the acronym INTJ is not a research finding. It is a design decision, taken by a specific person, for a specific purpose, in a specific year.

And what Myers added to Jung is substantial, and almost never credited to her. Four inventions: the four-dichotomy format in place of eight portraits; a questionnaire that produces the result with no clinician in the middle; the rule that the auxiliary runs in the attitude opposite the dominant; and the fourth letter. Two of those — the auxiliary rule and the fourth letter — are exactly what makes the INTJ exist as something separate from the INFJ. Without them you are the introverted intuitive of 1921 and nothing more.

In 1983, Harold Grant, Magdala Thompson and Thomas Clarke published From Image to Likeness. It is not a book of psychometrics. It is a book of Christian spirituality, published by Paulist Press, about a Jungian path within the Gospel journey. It is there that the four-slot stack with alternating attitudes was formalised — the one that now structures every conversation about cognitive functions, from forum to video to this site.

The rule is elegant: the attitudes alternate, position by position. In the INTJ that yields introverted intuition, extraverted thinking, introverted feeling, extraverted sensation — the stack you have seen a thousand times written as Ni–Te–Fi–Se. Grant and colleagues also added a developmental timetable, with age bands for the maturing of each function. It is from that book, and not from Jung or Myers, that the idea of the tertiary waking up in your early twenties comes.

The point almost nobody makes: Myers left the attitude of the tertiary function deliberately open, and the Myers & Briggs Foundation still leaves it open. Its own page on type dynamics describes dominant, auxiliary, tertiary and inferior without fixing whether the tertiary is introverted or extraverted. Which means that when someone tells you confidently that your tertiary feeling is Fi and not Fe, that person is quoting Grant — not Myers, and certainly not Jung.

Grant measured nothing either. The alternation is a choice of symmetry: handsome, easy to teach, with no study behind it. Reynierse, reviewing the literature, went as far as arguing that type dynamics as a whole adds no explanatory power to the four preferences taken on their own. That does not oblige you to throw the vocabulary away — it obliges you to know what it is: a grammar, not a result.

While the Jungian line was branching, two commercial branches grew alongside the trunk and are now mistaken for it. The first is David Keirsey, who from Please Understand Me in 1978 took the four letters and regrouped them into four observable temperaments, deliberately discarding the cognitive functions: he said he was interested in what people do, not in what goes on inside them.

In Keirsey’s system you are a Rational (NT), and in Please Understand Me II, in 1998, you are given the role of Mastermind — the contingency strategist, the one who keeps plans ready for scenarios that have not happened. It is a well-made portrait, and it needs saying plainly that it does not derive from Ni–Te. Keirsey arrived at that INTJ by another road, starting from Hippocrates and from behavioural typologies; the acronym coincides and the theory underneath disagrees.

The second branch is the likelier to have been your way in. NERIS Analytics, which runs 16Personalities, kept the four letters as a label and replaced the whole machinery underneath: the dichotomies became five continuous scales aligned to the five-factor model, and the cognitive functions were explicitly abandoned. The company says so itself, on the page where it sets out its theory.

The fifth scale is the one you have seen as a suffix: -A for assertive and -T for turbulent. It does not exist in the MBTI, does not exist in Grant and does not exist in Jung; in NERIS’ own description it is the identity scale, a relative of five-factor neuroticism. If “INTJ-T” felt like a hit, it is worth knowing that this part of the acronym is the newest and the least Jungian of the lot — and that what it describes is sensitivity to stress and self-doubt, not intuition.