An additional dichotomy dimension, Extraversion – Introversion, can be used for a more comprehensive understanding of personality.
According to Carl G. Jung's approach to personality, extraversion is the tendency toward active actions as a dynamic response to the events and information from the external world. Extraverted people draw the energy for their undertakings from the outside world. The outside world is the main driver of their actions and the main motivational factor. They typically have numerous contacts with others, even if their job does not require it.
Introversion is the tendency to reflect on one's own perceptions, thoughts and feelings. Introverted people draw the energy for their undertakings mainly from their inner world. The inner world is a very significant stimulus for their actions and is a very important motivational factor. They are unlikely to have numerous contacts with others, unless their job requires it.
Since in a workplace both extraverted and introverted people may have numerous contacts, this fact in itself cannot be used to conclude a slant to extraversion. Differentiating characteristics are better observed outside of workplace and in an informal environment. An extravert will energetically participate in conversations and activities. An introvert will try to find a place of solitude where he or she can avoid active contacts and can focus on their own thoughts and things they like.
Use the table above to identify extraverted vs. introverted personalities in other people.
E-I dimension together with T-F and S-N dimensions in Carl G. Jung typology form 8 possible combinations or groups with distinct behavioural qualities described above: EST, ESF, ENT, ENF, IST, ISF, INT, INF.