The Lenore Thomson Exegesis Wiki
More detail from the Place-Your-Stakes Exegesis.
To be an introvert, perhaps, is to be Oriented primarily by your sense of a "state of grace": a certain way of being and responding.
Extraverts can understand and appreciate this, too, but they are primarily Oriented by worldly callings. Extraverts are often in a better position to preach the value of a State Of Grace, because they understand it primarily from a perspective outside it, and they must engage in conscious effort to choose it.
Introverts find that they need to take worldly matters seriously, though, or their state of grace becomes hollow.
Lenore says that ITPs are attracted primarily to situations that bring their internal sense of logic into play. What matters, then, is not the results or the situation, but being "in the zone", responding faithfully to some idea manifesting itself in the present situation.
This can be baffling to people who expect that everyone has a consciously understood goal and purpose when they act. Within an ITP's typical self-experience, there is no goal or purpose, only responding to the situation as the situation calls for. One creates art, designs and builds, or understands for the sake of the process of doing these things, not for the end result, not for praise, not anything else.
Perhaps the same is true, in different forms, for all introverts, and even for extraverts to the extent that they take an introverted attitude seriously. Fi types aim to live each moment in harmony with the life spirit that they perceive in all things, Si types aim to live each moment upholding and doing their part in the cosmic order, and Ni types aim to live each moment heeding the call of something beyond. All are ways of existing in a certain way, for its own sake. As ways of consciously Orienting oneself, though, they aren't sufficient unto themselves: none can be fully achieved without attending to specific, genuinely culture- and situation-dependent concerns.