A reasonable case can be made that Jung would see the fourth function as opposite the dominant in distinctive ways, meaning that judgement is opposite perceiving and what is conscious is opposite an unconscious attitude. Further, Jung seems to suggest that the unconscious functions do not serve the "superior" or dominant function but have more important matters to attend to in the unconscious arena of the psyche. He noted that the "...inferior functions are found in service of"...the opposite attitude of the superior function (Jung, 1973, p.426). In addition, users of type often forget that inferior or unconscious functions are inferior to consciousness not in inferior in strength
in the psyche (Jung, 1971 p.450).
Jung sees that it is important for differentiation to occur among the functions or else we would not have types. He wrote that it is the habitual use of a function that sets a "definitive stamp on the character of the individual" (Jung, 1971, p.482). What is critical to understand is that the mental function used in a habitual attitude in consciousness is the source of the type; thus, the other functions work in the un-(or semi) conscious world of psychological energy.
And to this final theoretical point Jung suggests that a differentiating function is more likely to do so in the energy field (E or I) in which it resides (Jung, 1971, 405). Thus, if an individual is an extraverted type, then the other functions would be working in the introverted energy field, or vice versa. This would again suggest Myers formulation is closer to Jung's reflections on the importance of the balancing extraverted and introverted energies in the psyche.