Jung’s typological model regards psychological type as similar to left or right handedness: people are either born with, or develop, certain preferred ways of perceiving and deciding. The MBTI sorts some of these psychological differences into four opposite pairs, or “dichotomies”, with a resulting 16 possible psychological types. None of these types are “better” or “worse”; however, Briggs and Myers theorized that people innately “prefer” one overall combination of type differences. In the same way that writing with the left hand is difficult for a right-hander, so people tend to find using their opposite psychological preferences more difficult, even though they can become more proficient (and therefore behaviorally flexible) with practice and development.
The 16 types are typically referred to by an abbreviation of four letters—the initial letters of each of their four type preferences (except in the case of intuition, which uses the abbreviation “N” to distinguish it from introversion). For instance:
- ESTJ: extraversion (E), sensing (S), thinking (T), judgment (J)
- INFP: introversion (I), intuition (N), feeling (F), perception (P)
These abbreviations are applied to all 16 types.
Type Dynamics and Development
The interaction of two, three, or four preferences is known as “type dynamics”. Although type dynamics has received little or no empirical support to substantiate its viability as a scientific theory, Myers and Briggs asserted that for each of the 16 four-preference types, one function is the most dominant and is likely to be evident earliest in life. A secondary or auxiliary function typically becomes more evident (differentiated) during teenage years and provides balance to the dominant. In normal development, individuals tend to become more fluent with a third, tertiary function during mid-life, while the fourth, inferior function remains least consciously developed. The inferior function is often considered to be more associated with the unconscious, being most evident in situations such as high stress (sometimes referred to as being in the grip of the inferior function).
However, the use of type dynamics is disputed: in the conclusion of various studies on the subject of type dynamics, James H. Reynierse writes that “Type dynamics has persistent logical problems and is fundamentally based on a series of category mistakes; it provides, at best, a limited and incomplete account of type related phenomena”; and that “type dynamics relies on anecdotal evidence, fails most efficacy tests, and does not fit the empirical facts”. His studies gave the clear result that the descriptions and workings of type dynamics do not fit the real behavior of people. He suggests getting completely rid of type dynamics, because it does not help but hinders understanding of personality. The presumed order of functions 1 to 4 did only occur in one out of 540 test results.
The sequence of differentiation of dominant, auxiliary, and tertiary functions through life is termed type development. Note that this is an idealized sequence that may be disrupted by major life events.
The dynamic sequence of functions and their attitudes can be determined in the following way:
- The overall lifestyle preference (J-P) determines whether the judging (T-F) or perceiving (S-N) preference is most evident in the outside world; i.e., which function has an extraverted attitude
- The attitude preference (E-I) determines whether the extraverted function is dominant or auxiliary
- For those with an overall preference for extraversion, the function with the extraverted attitude will be the dominant function. For example, for an ESTJ type the dominant function is the judging function, thinking, and this is experienced with an extraverted attitude. This is notated as a dominant Te. For an ESTP, the dominant function is the perceiving function, sensing, notated as a dominant Se.
- The auxiliary function for extraverts is the secondary preference of the judging or perceiving functions, and it is experienced with an introverted attitude: for example, the auxiliary function for ESTJ is introverted sensing (Si) and the auxiliary for ESTP is introverted thinking (Ti).
- For those with an overall preference for introversion, the function with the extraverted attitude is the auxiliary; the dominant is the other function in the main four letter preference. So the dominant function for ISTJ is introverted sensing (Si) with the auxiliary (supporting) function being extraverted thinking (Te).
- The tertiary function is the opposite preference from the auxiliary. For example, if the Auxiliary is thinking then the Tertiary would be feeling. The attitude of the tertiary is the subject of some debate and therefore is not normally indicated; i.e. if the auxiliary was Te then the tertiary would be F (not Fe or Fi)
- The inferior function is the opposite preference and attitude from the Dominant, so for an ESTJ with dominant Te the inferior would be Fi.
Note that for extraverts, the dominant function is the one most evident in the external world. For introverts, however, it is the auxiliary function that is most evident externally, as their dominant function relates to the interior world.
Some examples of whole types may clarify this further. Taking the ESTJ example above:
- Extraverted function is a judging function (T-F) because of the overall J preference
- Extraverted function is dominant because of overall E preference
- Dominant function is therefore extraverted thinking (Te)
- Auxiliary function is the preferred perceiving function: introverted sensing (Si)
- Tertiary function is the opposite of the Auxiliary: intuition (N)
- Inferior function is the opposite of the Dominant: introverted feeling (Fi)
The dynamics of the ESTJ are found in the primary combination of extraverted thinking as their dominant function and introverted sensing as their auxiliary function: the dominant tendency of ESTJs to order their environment, to set clear boundaries, to clarify roles and timetables, and to direct the activities around them is supported by their facility for using past experience in an ordered and systematic way to help organize themselves and others. For instance, ESTJs may enjoy planning trips for groups of people to achieve some goal or to perform some culturally uplifting function. Because of their ease in directing others and their facility in managing their own time, they engage all the resources at their disposal to achieve their goals. However, under prolonged stress or sudden trauma, ESTJs may overuse their extraverted thinking function and fall into the grip of their inferior function, introverted feeling. Although the ESTJ can seem insensitive to the feelings of others in their normal activities, under tremendous stress, they can suddenly express feelings of being unappreciated or wounded by insensitivity.
Looking at the diametrically opposite four-letter type, INFP:
- Extraverted function is a perceiving function (S-N) because of the P preference
- Introverted function is dominant because of the I preference
- Dominant function is therefore introverted feeling (Fi)
- Auxiliary function is extraverted intuition (Ne)
- Tertiary function is the opposite of the Auxiliary: sensing (S)
- Inferior function is the opposite of the Dominant: extraverted thinking (Te)
The dynamics of the INFP rest on the fundamental correspondence of introverted feeling and extraverted intuition. The dominant tendency of the INFP is toward building a rich internal framework of values and toward championing human rights. They often devote themselves behind the scenes to causes such as civil rights or saving the environment. Since they tend to avoid the limelight, postpone decisions, and maintain a reserved posture, they are rarely found in executive-director-type positions of the organizations that serve those causes. Normally, the INFP dislikes being “in charge” of things. When not under stress, the INFP radiates a pleasant and sympathetic demeanor, but under extreme stress, they can suddenly become rigid and directive, exerting their extraverted thinking erratically.
Every type, and its opposite, is the expression of these interactions, which give each type its unique, recognizable signature.
|The Sixteen Types|
|US Population Breakdown|
|The table organizing the sixteen types was created by Isabel Myers (an INFP person).|
|Estimated percentages of the 16 types in the U.S. population.|