Some academic psychologists have criticized the MBTI instrument in research literature, claiming that it "lacks convincing validity data. Proponents and sellers of the test cite unblinded anecdotal predictions of individual behavior, and claim that the indicator has been found to meet or exceed the reliability of other psychological instruments. For most adults (75-90%), though not for children, the MBTI is reported to give the same result for 3–4 preferences when the test is administered to the same person more than once (although the period between measurements is not stated). Some studies have found strong support for construct validity, internal consistency, and test-retest reliability, although variation was observed.
The definitive published source of reference on the Myers-Briggs Type Indicator is The Manual produced by CPP, from which much of the information in this article is drawn, along with training materials from CPP and their European training partners, Oxford Psychologists Press. However, a popularized source of the model, with an original test, is published in David Keirsey's book Please Understand Me.
The registered trademark rights to the terms Myers-Briggs Type Indicator and MBTI have been assigned from the publisher of the test, CPP, Inc., to the Myers-Briggs Type Indicator Trust.
Fundamental to the Myers-Briggs Type Indicator is the theory of psychological type as originally developed by C. G. Jung. Jung proposed the existence of two dichotomous pairs of cognitive functions:
Jung went on to suggest that these functions are expressed in either an introverted or extraverted form. From Jung's original concepts, Briggs and Myers developed their own theory of psychological type, described below, on which the MBTI is based.
The 16 different types are often referred to by an abbreviation of four letters, the initial letters of each of their four type preferences (except in the case of iNtuition), for instance:
And so on for all 16 possible type combinations.
| Dichotomies | |
| Extraversion | Introversion |
| Sensing | Ntuition |
| 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).
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.
According to the Myers-Briggs typology model, each person uses one of these four functions more dominantly and proficiently than the other three; however, 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 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. 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.
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.
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.
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, 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, 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". 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.
Katharine Briggs' daughter, Isabel Briggs Myers, wrote a prize-winning mystery novel Murder Yet to Come in 1929 using typological ideas. She added to her mother's typological research, which she would progressively take over entirely. In 1942, the "Briggs-Myers Type Indicator" was created, and the Briggs Myers Type Indicator Handbook was published in 1944. The indicator changed its name to the modern form (Myers-Briggs Type Indicator) in 1956.
Judging vs. Perceiving
The most notable addition of Myers and Briggs to Jung's original thought is their concept that a given type's fourth letter (J or P) is determined by how that type interacts with the external world, rather than by the type's dominant function. The difference becomes evident when assessing the cognitive functions of Introverts.
To Jung, a type with dominant Introverted Thinking, for example, would be considered rational (Judging) because the decision-making function is dominant. To Myers, however, that same type would be irrational (Perceiving) because the individual uses an information-gathering function (either Extraverted iNtuition or Extraverted Sensing) when interacting with the outer world.
Orientation of the tertiary function
According to Jung, if the dominant cognitive function is introverted, the other functions are extraverted, and vice versa. However, many MBTI practitioners hold that the tertiary function is oriented in the same direction as the dominant function. Using the INTP type as an example, the orientation would be as follows:
From a theoretical perspective, noted psychologist H.J. Eysenck calls the MBTI a moderately successful quantification of Jung's original principles as outlined in Psychological Types.
Using psychometric techniques, such as item response theory, the MBTI will then be scored and will attempt to identify the preference, and clarity of preference, in each dichotomy. After taking the MBTI, participants are usually asked to complete a Best Fit exercise (see above) and then given a readout of their Reported Type, which will usually include a bar graph and number to show how clear they were about each preference when they completed the questionnaire.
During the early development of the MBTI thousands of items were used. Most were eventually discarded because they did not have high midpoint discrimination, meaning the results of that one item did not, on average, move an individual score away from the midpoint. Using only items with high midpoint discrimination allows the MBTI to have fewer items on it but still provide as much statistical information as other instruments with many more items with lower midpoint discrimination. The MBTI requires five points one way or another to indicate a clear preference.
Isabel Myers had noted that people of any given type shared differences as well as similarities. At the time of her death, she was developing a more in-depth method of measuring how people express and experience their individual type pattern. This tool is called the MBTI Step II.
A Step III is also being developed in a joint project involving the following organizations: CPP, the publisher of the whole family of MBTI works; CAPT (Center for Applications of Psychological Type), which holds all of Myers' and McCaulley's original work; and the MBTI Trust, headed by Katharine and Peter Myers. Step III will further address the use of perception and judgment by respondents.
In addition, the Type Differentiation Indicator (TDI) (Saunders, 1989) is a scoring system for the longer MBTI, Form J, which includes the 20 subscales above, plus a Comfort-Discomfort factor (which purportedly corresponds to the missing factor of Neuroticism). This factor includes seven additional scales to indicate a sense of overall comfort and confidence versus discomfort and anxiety: guarded-optimistic, defiant-compliant, carefree-worried, decisive-ambivalent, intrepid-inhibited, leader-follower, and proactive-distractible. Also included is a composite of these called "strain." Each of these comfort-discomfort subscales also loads onto one of the four type dimensions, for example, proactive-distractible is also a judging-perceiving subscale. There are also scales for type-scale consistency and comfort-scale consistency. Reliability of 23 of the 27 TDI subscales is greater than .50, "an acceptable result given the brevity of the subscales" (Saunders, 1989).
Type not trait: The MBTI sorts for type; it does not indicate the strength of ability. The questionnaire allows the clarity of a preference to be ascertained (Bill clearly prefers introversion), but not the strength of preference (Jane strongly prefers extraversion) or degree of aptitude (Harry is good at thinking). In this sense, it differs from trait-based tools such as 16PF. Type preferences are polar opposites: a precept of MBTI is that you fundamentally prefer one thing over the other, not a bit of both.
Own best judge: Individuals are considered the best judge of their own type. While the MBTI questionnaire provides a Reported Type, this is considered only an indication of their probable overall Type. A Best Fit Process is usually used to allow the individual to develop their understanding of the four dichotomies, form their own hypothesis as to their overall Type and compare this against the Reported Type. In more than 20% of cases, the hypothesis and the reported type differ in one or more dichotomies: the clarity of each preference, any potential for bias in the report and, often, a comparison of two or more whole Types may then be used to help the subject determine his or her own Best Fit.
No right or wrong: No preference or total type is considered 'better' or 'worse' than another - they are all, as in the title of the book on this subject by Isabel Briggs Myers, Gifts Differing.
Voluntary: It is considered unethical to compel anyone to take the Myers-Briggs Type Indicator. It should always be taken voluntarily.
Confidentiality: The result of the MBTI Reported and Best Fit type are confidential between the individual and administrator and, ethically, not for disclosure without permission.
Not for selection: Because the MBTI measures preferences instead of aptitude - and because there are no right or wrong types - it is not considered a proper instrument for purposes of employment selection. Many professions contain highly competent individuals of different types with complementary preferences.
Importance of proper feedback: Individuals should always be given detailed feedback from a trained administrator and an opportunity to undertake a Best Fit exercise to check against their Reported Type. Feedback can be given in person or, where this is not practical, by telephone or electronically.
| The Sixteen Types | |||
| ISTJ | ISFJ | INFJ | INTJ |
| ISTP | ISFP | INFP | INTP |
| ESTP | ESFP | ENFP | ENTP |
| ESTJ | ESFJ | ENFJ | ENTJ |
| The table organizing the sixteen types was created by Isabel Myers (an INFP). | |||
| U.S.A. Population Breakdown | |||
| ISTJ 11.6% | ISFJ 13.8% | INFJ 1.5% | INTJ 2.1% |
| ISTP 5.4% | ISFP 8.8% | INFP 4.3% | INTP 3.3% |
| ESTP 4.3% | ESFP 8.5% | ENFP 8.1% | ENTP 3.2% |
| ESTJ 8.7% | ESFJ 12.3% | ENFJ 2.4% | ENTJ 1.8% |
| Estimated percentages of the 16 types in the American population using inferential statistics. The figures above are from a random sampling of 3009 people culled from a total pool of 16,000 using the 1998 MBTI Form M. The individuals whose form results were used in this random sampling were not provided with the data to verify or question their accuracy. But these numbers do provide a working base on which to build further understanding and development of the model as extrapolated to larger populations. It should be noted that some types are more likely to take the MBTI than others (such as the INFP) and raw statistics prove unreliable because of this. | |||
The interaction of two, three, or four preferences is known as type dynamics. 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 funciton 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).
The sequence of differentiation of dominant, auxiliary and tertiary functions through life is termed type development. This is an idealized sequence which may be disrupted by major life events; for example, the death or serious illness of a parent during childhood is considered commonly to halt full development of the auxiliary function.
The dynamic sequence of functions and their attitudes can be determined in the following way:
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.
A couple of examples of whole types will help to clarify this further.
Taking the ESTJ example above:
The dynamics of the ESTJ are found in the primary combination of Extraverted Thinking being their dominant function and Introverted Sensing being their auxiliary function: The dominant tendency to order the ESTJ's environment, to set clear boundaries, to clarify roles and timetables and to direct the activities around them is supported by the facility for using past experience in an ordered and systematic way to help organize themselves and others. ESTJs, for instance, may enjoy planning trips for groups of people to achieve some goal or to perform some culturally uplifting function. Because of their ease of directing others and their facility of managing their own time, they will 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. Though 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:
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 "signature" that can be recognized.
Big Five
McCrae and Costa present correlations between the MBTI scales and the Big Five personality construct, which is a conglomeration of characteristics found in nearly all personality and psychological tests. The five personality characteristics are extraversion, openness, agreeableness, conscientiousness, and emotional stability (or neuroticism). The following study is based on the results from 267 men followed as part of a longitudinal study of aging. (Similar results were obtained with 201 women.)
These data suggest that four of the MBTI scales are related to the Big Five personality traits. These correlations show that E-I and S-N are strongly related to extraversion and openness respectively, while T-F and J-P are moderately related to agreeableness and conscientiousness respectively. The emotional stability dimension of the Big Five is largely absent from the original MBTI (though the TDI, discussed above, has addressed that dimension).
These findings led McCrae and Costa, the formulators of the Five Factor Theory, to conclude, "correlational analyses showed that the four MBTI indices did measure aspects of four of the five major dimensions of normal personality. The five-factor model provides an alternative basis for interpreting MBTI findings within a broader, more commonly shared conceptual framework." However, "there was no support for the view that the MBTI measures truly dichotomous preferences or qualitatively distinct types, instead, the instrument measures four relatively independent dimensions."
It has been estimated that between a third and a half of the published material on the MBTI has been produced for conferences of the Center for the Application of Psychological Type (which provides training in the MBTI) or as papers in the Journal of Psychological Type (which is edited by Myers-Briggs advocates). It has been argued that this reflects a lack of critical scrutiny.
Unlike other personality measures, such as the Minnesota Multiphasic Personality Inventory or the Personality Assessment Inventory, the MBTI lacks validity scales to assess response styles such as exaggeration or impression management. The MBTI has not been validated by double-blind tests, in which participants accept reports written for other participants, and are asked whether or not the report suits them, and thus may not qualify as a scientific assessment. Validity has also been questioned on theoretical grounds.
In her research, Isabel Myers found that the proportion of different personality types varies by choice of career or course of study. However, some other researchers examining the proportions of each type within varying professions report that the proportion of MBTI types within each occupation is close to that within a random sample of the population.
With regard to factor analysis, one study of l29l college-aged students found six different factors instead of the four used in the MBTI. In other studies, researchers found that the JP and the SN scales correlate with one another.

Official websites
Criticism of the MBTI
The 16 personality types
Free online Jungian typology tests