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 held 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 like to “have matters settled”.
Those types who prefer perception 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, perceptive 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 the ENTJ type is extraverted, the J indicates that the dominant function is the preferred judging function (extraverted thinking). The ENTJ type introverts the auxiliary perceiving function (introverted intuition). The tertiary function is sensing and the inferior function is introverted feeling.
Because the INTJ type is introverted, however, the J instead indicates that the auxiliary function is the preferred judging function (extraverted thinking). The INTJ type introverts the dominant perceiving function (introverted intuition). The tertiary function is feeling and the inferior function is extraverted sensing.