Jung’s original work on Psychological type was adapted into several other personality theories. These theories are often blurred together in internet discussions although they are different. This article assumes you are already generally familiar with the various Jungian personality theories (MBTI/Keirsey/Socionics) so I’m focusing on clarifying the differences between theories rather than providing an explanation of how each theory works.
Jung’s Psychological Types
Developed By: Swiss Psychiatrist Carl Gustav Jung
Alternative INTJ Terms: Introverted Intuitive
Jung developed the frame work of personality types later used by Myers-Briggs and other personality theorists. His theory consists of four functions (S/N and T/F) which are modified by introversion and extraversion to create eight psychological types. The cognitive processes are Se/Si, Ne/Ni, Te/Ti, Fe/Fi. In Jung’s theory, “rational” is used to describe the judging functions thinking and feeling and “irrational” is used to describe the perceiving functions sensation and intuition.
There was no type labelled as an “INTJ” in Jung’s theory as the 16 types were coined in a later theory.
Myers-Briggs
Developed By: Katharine Cook Briggs and psychological theorist Isabel Briggs Myers
Alternative INTJ Terms: Introverted Intuition Supported By Thinking
Katharine Cook Briggs and her daughter Isabel Briggs Myers developed the Myers-Briggs Type Indicator (MBTI) based on a modified version of Jung’s theory. Their goal was to make Jung’s theory more understandable and useful to people. Myers-Briggs stuck with Jung’s cognitive functions and added the J/P dimension to create 16 personality types. The Myers-Briggs theory is based heavily on cognitive processes and how people think and feel.
Most discussions about personality theories on the internet is based on a mixture of the Myers-Briggs theory and Keirsey’s Temperament sorter.
Keirsey’s Temperament Sorter
Developed By: American psychologist David Keirsey
Alternate INTJ Terms: Mastermind
Keirsey’s personality theory is based on a combination of the four temperaments and Jung’s original theory. His theory only uses the four scales (I/E, N/S, T/F, J/P) and does not incorporate the cognitive processes to create each personality profile. Keirsey’s theory is based on people’s core needs and long term observable behavior whereas Myers-Briggs primarily describes what people think and feel.
A significant portion of what is discussed about personality typology in internet communities comes from Keirsey’s contributions. If you group the types as NT, NF, SP and SJ, you are referencing groupings Keirsey introduced. Keirsey believed the differences between N and S types were the most important, followed by T/F for N types and J/P for S types. He is also the one who coined the term “Mastermind” for INTJs. Many of the tests available online use the four scale model similar to The Keirsey Temperament Sorter.
Keirsey’s INTJ profile focuses on behavior more than thought processes, but doesn’t necessarily clash with the Myers-Briggs version of the type.
Socionics
Developed by: Lithuanian researcher Aušra Augustinavičiūtė
Alternate INTJ Terms: The Analyst (INTj) or The Observer (INTp)
Augustinavičiūtė used a combination of Jung’s personality type theory and Antoni Kępiński’s information metabolism theory to develop the socionics theory. Augustinavičiūtė believed each type had a distinct role to play in society, which is the reason the name “socionics” was chosen. Like Jung’s theory, socionics has eight functions (socionics: information aspects) that combine to create 16 different personality types (socionics: sociotypes). The letters making up the types in Socionics are the same as Jung’s, but the functions are in a different order and the last letter of a type is always lowercase. For this reason, using a lower case letter for J/P to show a “weak” function may be confused for displaying a socionics type.
The most striking difference between the socionics profiles and those of other Jungian theories is the focus on physical appearance. The profiles describe the shape of the face and body, posture, gestures, clothing choices and voice. Intertype relations, social roles and the interaction of functions between types is prominent in the descriptions, rather than behavior or how the types think which is prominent in other Jungian theories.
Many people think the socionics INTj is actually the INTp and vice versa. It is stated on the socionics site that this is a myth and there is no direct conversion of types between the systems for introverts. Therefore, some INTJs will relate to the INTj profile more and others will relate more to the INTp. However, in socionics the cognitive functions are swapped — the INTj is TiNe and the INTp is NiTe, so the INTj functions directly conflict with the Myers-Briggs INTJ.