Quasi-defining statements
p. 222: "...draws our attention to immediate sensory phenomena. ... It prompts an interest in perception itself--the process of recognizing and interpreting what we take in."
p. 223: "Introverted Intuition would prompt us to liberate our sense impressions from their larger context, thereby creating new options for perception itself."
p. 229: "Introverted Intuitions are not really ideas. They're like trains at the edge of articulated knowledge. You can't claim them or advocate them. You put on a hat, grab hold of a boxcar door, and see where they go."
p. 153: "Introverted Intuition suggests that absolute meaning is an illusion--the result of having incomplete information."
As a dominant function:
p. 225: "For INJs, patterns aren't 'out there' in the world, waiting to be discovered. They're part of us--the way we make sense of the riot of energy and information impinging on our systems. A disease syndrome is a useful construct, but that's all it is--an aggregate of observations attached to a label, telling us what to see and how to deal with it."
p. 225: "Where Extraverted Intuitives see many behavioral options, INJs acknowledge many conceptual standpoints. They experience no need to declare one inherently better than another. Indeed, these types have the disconcerting habit of solving a problem by shifting their perspective and defining the situation some other way."
p. 234: "For INJs, truth isn't about logic. Truth is a frame of reference, a way of organizing information, which serves one set of needs or another."
Proposed definition #1: Seeing past interpretations
Introverted Intuition (Ni) is the attitude that whatever is manifest (apparent, observable, described) is only the tiniest fraction of the total reality and all of its potential, and it is manifest only because it serves a purpose--a purpose that it achieves by exploiting a certain way of interpreting or navigating by signs. Ni is attunement to what lurks in the shadow of that manifestation. What is that assumed way of interpreting or navigating? What could we see if we were free of it?
Proposed definition #2: What cannot be said?
Introverted Intuition is the attitude of attunement to what cannot be said, by virtue of the structuring that "saying" requires.
For example: At work, we don't dare say our true feelings (or we can only say them if they're positive), because we know that sharing them would bring dire economic consequences. There is no other way, because the structure of the workplace (people working cooperatively to get stuff done that they get paid for) requires that people refrain from saying anything that might put their loyalty in doubt. If an accountant, in his office, says that he loves accounting, you view this as meaningless because, well, what else is he going to say? In fact, he might very well hate accounting. You have to be highly attuned to what's really going on in order to read the true meaning of what people say--which is often the opposite of the literal meaning of their words. (See Eric Berne.)
For example: Why do we put North at the top of most maps? Because the mapmaking tradition began among northern-dwelling people, who considered people who lived further south to be less important. Putting North at the top of the map frames geography in a way that, perhaps unwittingly, conveys the belief that Europeans are better or more important than Africans. This can't be said by anything within the map; the very way that the map is structured and related to reality says it.
For example: What does music mean? You can't say it. It's ineffable. (See Introverted Intuition and the Meaning of Music.) What is God? What is spirit? Any attempt to capture these things in words only cheapens them.
Introverted Intuition is an attitude of "seeing through" the distortion that any interpretation creates, to see the underlying reality. It's a left-brain attitude in that it's sign- and symbol-oriented: attempting to grasp the system of interpretation that makes any particular way of representing reality work, as a prerequisite for using that system. From an Ni ego-state, you want to understand the assumptions of a system of representation before you use the system, so that you can use it with true freedom--including the freedom to use the built-in interpretations in ways that violate those assumptions.
Proposed definition #3: Orientation by manner of orientation
Introverted Intuition is a way of orienting yourself to your environment by consciously attending to the expected interpretations of things. In this manner of orientation, you hold agnostic about whether those interpretations are true. You view them as expected interpretations, nothing more. Your world is a world of expected interpretations defined by others; you navigate through those interpretations and use them without regard to whether they're true, always keeping the interpretations separate in your mind from the actual objects.
For example, whereas from an Extraverted Sensation perspective, you might feel very impressed upon meeting a man wearing a fancy Italian suit (signs call forth a natural response and need no interpretation); from an Ni perspective, you would consciously say to yourself that he's wearing an Italian suit and this is supposed to make you think he's wealthy or upper-class or really has his act together or something like that, and therefore is supposed to make you feel impressed (signs and what they mean are connected only arbitrarily). Whether he really does have his act together is a matter upon which you reserve judgement. Consequently you don't feel impressed. You merely note the expected interpretation as no less a part of your environment than the suit itself.
Without knowing the expected interpretations of a system--the way signs are interpreted within that system, and the expected responses that make the system work--you can't get oriented via Ni. The expected interpretations must be stabilized and clear to you. Then you can comment from an outside perspective, or see ways to respond to the signs that violate the system's assumptions, or simply know how to operate the thing. First you have to get "outside" it, then you can deal with it. The process of "getting outside it" can take a long time. As you identify expected interpretations, you find yourself uncovering ever more and more hidden assumptions, and you feel the need to distance yourself from those, too, before you get your hands dirty or draw a conclusion.
Proposed definition #4: Just knowing
Ni is a way of knowing (or at least thinking you know) that bypasses reason, facts, evidence, the expected or intended interpretations of signs, or anything you can point to, simply giving you an awareness or belief that seems indisputably true to you, period. You can't tell by introspection how you got this idea. There is no thought process. There is only tuning into this form of awareness and just knowing.
For example: You've been interviewing candidates for a job. One of them has all the credentials, and scored the highest on all the company-defined criteria for the job. Another of them was pretty good but not in the same league. You have a sense about the high-scorer, though, that he's bad news, and that the "so-so" one will work out well. You can't point to anything that's let you to this conclusion, you can't justify your belief, but you have this sense just the same. To trust this unjustifiable idea is to orient by introverted intuition.
For example: The song Bad Moon Rising illustrates an Ni sense of danger. The belief is strong yet vague.
For example: A co-worker calls you on the phone and says that he has a cold and won't be able to come in that day. You "see through" what he said: you "just know" it's a lie: really he has an interview at another company. You can't point to a single thing that leads you to such a specific conclusion, and yet there it is.
For example: You are trying to solve some problem--an interpersonal problem, a mathematical problem, it could be anything. Everything seems to be snared and confused. You ask yourself, "What's really going on here?" And an answer comes.
For example: Jack Groverland (ENTJ?) preaches to "be still" and just "tune in to what that greater intelligence that is the universe wants you to do."
With extraverted intuition, you bypass the socially defined interpretations of signs by broadening the context, and thus relate to other people's ideas in a definite way: you propose something "outside the box"--the box that other people are thinking in. You expect that other people's minds will be blown, probably pleasantly, inducing a feeling of "wow!" With introverted intuition, you also bypass the expected interpretations of signs, but your belief is self-contained, and you have no sense that anyone else would find it interesting or compelling. It came to you, for no reason that you can fathom, and you can't show anyone else any reason why they should take it seriously. The belief might be very specific, too vague for words, or even too specific for words.
Orienting by Ni, you are likely to view belief as something that simply arises within each person when they tune into it. If two people have different beliefs, there is no resolving it. I have my belief and you have yours. End of story. New ideas or evidence seem beside the point. If you think there's a bad moon rising, how could mere "evidence" persuade you otherwise?
Lenore doesn't talk much about this
Lenore's writing doesn't emphasize this aspect of Ni. It's hidden in little notes here and there, like the way tertiary Ni can give ISFPs the will to hold to a belief even when others don't agree with it, or the way ENTJs "see around the corners" of an organization's official rules. For the most part, Lenore emphasizes neutrality between conflicting ideas. The present hypothesis proposes that this emphasis is a possible, maybe illustrative, but not necessary consequence of the basic idea: "just knowing" in a way that bypasses built-in or conventional interpretations of signs: seeing past the signs, and just "getting" the truth (or at least thinking you have).