Jordan's thoughts in Jung's "Psychological Types".
"the reflective character, the introvert, though certainly trying to deal with his unruly affects, is in reality more influenced by his passions than the man whose life is consciously guided by desires oriented to objects. The latter, the extravert, tries to get away with this all the time, but is forced to experience how his subjective thoughts and feelings constantly stand in his way. He is far more influenced by his psychic inner world than he suspects. He cannot see it himself, but the people around him, if observant, will always detect the personal purpose in his striving ". <...>.
"The other, the introvert, with his conscious thought-out intentions, always overlooks what the people around him see only too clearly, that his intentions are really subservient to powerful impulses, lacking both aim and object, and are in a high degree influenced by them."
"The observer and critic of the extravert is liable to take the parade of thinking and feeling as a thin covering that only imperfectly conceals a cold and calculated personal aim. Whereas the man who tries to understand the introvert will readily conclude that vehement passions are only with difficulty held in check by apparent sophistries. "