Where Did INFJ Come From? A Timeline from Jung to Four Letters

Published 2026-08-31 · imINFJ

You’re asking where INFJ came from — which is really two questions: where did type theory start, and when did the four letters INFJ get fixed as a label. Below is a timeline I’ve put together. Where I can cite a source, I do. Where it’s contested, I say so.

If you only need what the four letters mean, start with What Is INFJ?. This page is about history and sources.

In one sentence

Jung laid the foundation, the Myers-Briggs team built the sixteen-type house, and INFJ is one room number — Advocate is a nickname someone hung on the door later, not a Jung quote.

Timeline

1921 — Jung’s Psychological Types

Swiss psychiatrist Carl Jung published Psychological Types. He proposed:

• Two attitudes: Introversion and Extraversion
• Four psychological functions: Thinking, Feeling, Sensing, Intuition

Each person leads with one function in an introverted or extraverted attitude. Jung discussed eight dominant-function types (e.g. introverted intuition). He did not use today’s four-letter, sixteen-type table, and he did not use the code INFJ.

Everything that followed — including MBTI — traces back here.

1920s — Briggs and Myers begin

Katharine Cook Briggs studied Jung’s work and began systematically observing personality differences. Her daughter Isabel Briggs Myers pushed the framework toward practical use — especially during WWII, when she wanted to help women entering the workforce find suitable roles.

Their work was not a straight translation of Jung. They added the Judging / Perceiving dimension on top of Jung’s eight types, expanded the combinations to sixteen types, and wrote questionnaire items for each.

1940s–1960s — Instrument and manual

• Around 1943: early versions of the MBTI questionnaire appear (often cited as a starting point in biographies and histories)
• 1962: Isabel publishes the first MBTI manual; the indicator enters research and applied settings
• 1980 (drafted 1974): Gifts Differing — one of the best books for understanding how the mother-daughter project actually thought

In this system, INFJ means Introverted (I) + Intuitive (N) + Feeling (F) + Judging (J). It is one of sixteen four-letter combinations, not a type Jung named himself.

1990s onward — Commercialization, the web, nicknames

Rights to MBTI-related materials were developed commercially (including through CPP, Inc. and predecessors). Corporate training and career counseling scaled the model. At the same time, academic criticism of retest reliability, dichotomous scoring, and comparison to models like the Big Five kept accumulating — more on that below.

In the 2010s, sites like 16Personalities gave each type a plain-language name; INFJ became the Advocate, spreading through free online tests. The name fits the pattern of idealism plus quiet persistence, but it is not official Jung or Myers terminology.

Earlier, David Keirsey called INFJ the Counselor in the temperament tradition. Different schools, different nicknames — not a right/wrong contest.

Two bloodlines — don’t merge them

imINFJ’s rule: know who said what, then decide how far you trust each layer.

Who actually named INFJ “Advocate”?

Three stories that can all be true:

1. Keirsey line: Counselor — temperament and role description
2. 16Personalities: Advocate — mass-market memory and branding
3. Official MBTI materials: usually just the four letters INFJ, without a required nickname

When you see “INFJ Advocate” online, it’s one popular label for the same preference pattern — not a term from Psychological Types.

Why does academia push back?

Not “MBTI is all wrong” — but what it’s good for and what psychometrics demands are different things:

• Retest drift: many people get a different type weeks later; a strict diagnostic tool shouldn’t wobble like that
• Forced binaries: most people sit in the middle of I/E, N/S, etc.
• Relation to Big Five: correlated in places, not interchangeable
• Popularity vs. evidence: workplaces and creators love it; top journals rarely treat it as a gold standard

Those criticisms matter for imINFJ: we use type language for self-understanding and communication, not an immovable medical stamp.

What I’m still sorting out

• INFJ population rates vary wildly by sample; “rarest type” is mostly internet narrative
• The cognitive function stack (Ni-Fe-Ti-Se) is a later Jungian development (John Beebe and others), not spelled out item-by-item in Myers’s original questionnaire
• Free online quizzes and formal MBTI Step I/II are not the same instrument

Read next

• Who are the experts and authorities in this field? — who to read and how schools differ
• What Is INFJ? — the four letters and rarity claims
• INFJ cognitive functions — how Ni-Fe-Ti-Se actually work

This is a research note, not a psychological diagnosis. If you’re struggling, please seek help from a qualified professional.