The four dichotomies
Dichotomies
Extraversion Introversion
Sensing iNtuition
Thinking Feeling
Judging Perceiving
The four pairs of preferences or dichotomies are shown in the table to the right.

Note that the terms used for each dichotomy have specific technical meanings relating to the MBTI which differ from their everyday usage. For example, people with a preference for Judging over Perceiving are not necessarily more "judgmental" or less "perceptive".

Nor does the MBTI instrument measure aptitude; it simply indicates for one preference over another. Someone reporting a high score for Extraversion over Introversion cannot be correctly described as 'more' Extraverted: they simply have a clear preference.

Point scores on each of the dichotomies can vary considerably from person to person, even among those with the same type. However, Isabel Myers considered the direction of the preference (for example, E vs. I) to be more important than the degree of the preference (for example, very clear vs. slight).[13]


[edit] Attitudes: Extraversion (E) / Introversion (I)
The preferences for Extraversion (thus spelled in Myers-Briggs jargon) and Introversion are sometimes referred to as attitudes. Briggs and Myers recognized that each of the functions can show in the external world of behavior, action, people and things (extraverted attitude) or the internal world of ideas and reflection (introverted attitude). The Myers-Briggs Type Indicator sorts for an overall preference for one or the other of these.

People with a preference for Extraversion draw energy from action: they tend to act, then reflect, then act further. If they are inactive, their level of energy and motivation tends to decline. Conversely, those whose preference is Introversion become less energized as they act: they prefer to reflect, then act, then reflect again. People with Introversion preferences need time out to reflect in order to rebuild energy. The Introvert's flow is directed inward toward concepts and ideas and the Extravert's is directed outward towards people and objects. There are several contrasting characteristics between Extraverts and Introverts: Extraverts desire breadth and are action-oriented, while introverts seek depth and are thought-oriented.

The terms Extravert and Introvert are used in a special sense when discussing the Myers-Briggs Type Indicator.


[edit] Functions: Sensing (S) / iNtuition (N) and Thinking (T) / Feeling (F)
Jung identified two pairs of psychological functions: the two Perceiving functions, Sensing and iNtuition (thus spelled in Myers-Briggs jargon to distinguish it from Introversion); and the two Judging functions, Thinking and Feeling. Although each person uses one of these four functions more dominantly and proficiently than the other three, all four functions are used at different times depending on the circumstances.

Sensing and iNtuition are the information-gathering (Perceiving) functions. They describe how new information is understood and interpreted. Individuals who prefer Sensing are more likely to trust information that is in the present, tangible and concrete: that is, information that can be understood by the five senses. They tend to distrust hunches that seem to come out of nowhere. They prefer to look for details and facts. For them, the meaning is in the data. On the other hand, those who prefer iNtuition tend to trust information that is more abstract or theoretical, that can be associated with other information (either remembered or discovered by seeking a wider context or pattern). They may be more interested in future possibilities. They tend to trust those flashes of insight that seem to bubble up from the unconscious mind. The meaning is in how the data relates to the pattern or theory.

Thinking and Feeling are the decision-making (Judging) functions. The Thinking and Feeling functions are both used to make rational decisions, based on the data received from their information-gathering functions (Sensing or iNtuition). Those who prefer Feeling tend to come to decisions by associating or empathizing with the situation, looking at it 'from the inside' and weighing the situation to achieve, on balance, the greatest harmony, consensus and fit, considering the needs of the people involved. Those who prefer Thinking tend to decide things from a more detached standpoint, measuring the decision by what seems reasonable, logical, causal, consistent and matching a given set of rules.

As noted already, people with a Thinking preference do not necessarily, in the everyday sense, 'think better' than their Feeling counterparts; the opposite preference is considered an equally rational way of coming to decisions (and, in any case, the MBTI assessment is a measure of preference, not ability). Similarly, those with a Feeling preference do not necessarily have 'better' emotional reactions than their Thinking counterparts.


[edit] Dominant Function
Although people use all four cognitive functions, one function is generally used in a more conscious and confident way. This dominant function is supported by the secondary (auxiliary) function, and to a lesser degree the tertiary function. The fourth and least conscious function is always the opposite of the dominant function. Jung and Myers called this the inferior, or shadow, function.

The four functions operate in conjunction with the attitudes (Extraversion and Introversion). Each function is used in either an extraverted or introverted way. A person whose dominant function is extraverted intuition, for example, uses intuition very differently from someone whose dominant function is introverted intuition.


[edit] Lifestyle: Judging (J) / Perception (P)
Myers and Briggs added another dimension to Jung's typological model by identifying that people also have a preference for using either the Judging function (Thinking or Feeling) or their Perceiving function (Sensing or iNtuition) when relating to the outside world (extraversion).

Myers and Briggs taught that types with a preference for Judging show the world their preferred Judging function (Thinking or Feeling). So TJ types tend to appear to the world as logical, and FJ types as empathetic. According to Myers[2], Judging types prefer to "have matters settled." Those types ending in P show the world their preferred Perceiving function (Sensing or iNtuition). So SP types tend to appear to the world as concrete and NP types as abstract. According to Myers[2], Perceiving types prefer to "keep decisions open."

For Extraverts, the J or P indicates their dominant function; for Introverts, the J or P indicates their auxiliary function. Introverts tend to show their dominant function outwardly only in matters "important to their inner worlds".[2] For example:

Because ENTJ types are Extraverts, the J indicates that their dominant function is their preferred Judging function (Extraverted Thinking). ENTJ types introvert their auxiliary Perceiving function (Introverted iNtuition). The tertiary function is Sensing and the inferior function is Introverted Feeling.

Because INTJ types are Introverts, the J indicates that their auxiliary function is their preferred Judging function (Extraverted Thinking). INTJ types introvert their dominant Perceiving function (Introverted iNtuition). The tertiary function is Feeling, and the inferior function is Extraverted Sensing.