That's actually been one of my biggest stumbling blocks, because I can't seem to find good descriptions of Ni? I don't relate to the sort of "psychic" vibe the function seems to imply...but the only times I can fully utilize the Ne "brainstorming" seems to be when I'm worrying about all the things that can go wrong in a situation.
For what it's worth, I also seem to use Ne mostly for thinking up negative possibilities. That may be an indication of it being in your shadow functions?
I can't comment on how INTP you seem since I don't know any IRL, but I second Z Buck that what you've said in this thread seems INFJ.
I'm not sure of how "psychic" you think Ni is, as in knowing winning lottery numbers or something, but that's definitely not it
(there are some people who believe this, BTW). It's more that Ni is pretty future-focused. It's like . . . over the course of a lifetime, someone using Ni takes in all the information that they've ever received or encountered through study or through living life (Se data) and then tries to make universal principles out of it. Then they use these principles when they encounter what's happening now to try to figure out what will most likely happen in the future, and using what's happening now to add to their universal principles.
For an example of Ni principles, take the song "Affirmation" by Savage Garden (one of my favorite bands), lyrics written by Darren Hayes (who I believe to be ENFJ). One line says "I believe that junk food tastes so good because it's bad for you." The principle: things that are bad for you generally seem more fun/desirable because of the person believing they're bad for them. So if someone using Ni believes this principle to be true, then when they're with someone else who's trying to decide between two things that are otherwise equal but one they believe is healthy and the other less than healthy (doesn't have to be food-related at all), the Ni-user will probably conclude that this other person will be naturally drawn to what they believe is unhealthy (although whether the person actually chooses this unhealthy thing is far more complicated).
Or, for instance, if I'm with a good friend who I've known for years, I've accumulated information over the years about what things they're likely to do when and under what circumstances. So when certain circumstances come up, it's almost an unconscious process that I will get hunches saying "This person is likely to do ____ because of being in these circumstances." But the hunch is based on info of what this person has done over the years; it's not out of nowhere.
I understand how Ne is supposed to be like brainstorming, so as an analogy...if Ne use is like being faced with a problem or question and then coming up with all sorts of answers and ideas as a response that jump off one another, then is Ni use like seeing one clear answer relatively quickly, and then pulling things from outside in to further develop it?
For Ni, it is like one hunch comes up. But there two caveats: there's not always a hunch. There isn't always enough accumulated "Se data" or principles built up for every situation, and sometimes I get no hunch at all even if I really, really want one! The other caveat is that sometimes I'll see a couple likely scenarios that will happen because of a couple pieces of information that I don't have. Sometimes I'll think things like: "If this person is doing this for reason X, then they will mostly likely do action A. But if they're actually doing it for reason Y, then they will most likely do action B." And the disparity in my thinking is because of not having the information of whether they're doing it for reason X or Y. But it's not a million and one possibilities.
I'm not sure what you mean by "pulling things in from the outside to further develop it." It's more like if I get an Ni hunch, I will analyze it further in my own head, mostly trying to make it more clear to myself. Sometimes it will be a really vague notion, and I'll need to wait for it to become more clear. Or sometimes it's a clear notion, but the reasoning behind it is not so clear (not at all that it's not there or not valid, it's just that it's less in focus), and so I'll work on trying to make the reasoning more clear (using Ti) so that I can explain it to others if asked.
[Edit] I want to add too that Ni isn't all about finding "one possibility." Since it's a perceiving function, it's always working to refine itself. And looking at multiple perspectives is also a big part of what Ni is. It's like looking at something through different lenses and believing that all of these lenses are valid and needed in order to see the complete picture. For instance, if you're looking at a novel, you might examine it through the perspective of characters, and then through setting, and then through theme, etc. Or if you're an English major, it might be through gender theory, New Criticism, deconstruction of binaries, etc. Someone using Ni would believe that all of these perspectives (and many others) are needed to fully understand the novel (the object) completely, and they could shift talking from one perspective to another perspective and still feel like they're still talking about the same whole object, even if one perspective seems to contradict the other. But this is different than multiple possibilities.
Here is a link to a copy of an article that's probably my favorite description of what Ni is. I would have linked directly to the article, but it seems like it doesn't exist anymore.
Here is a link to a discussion on this site that some have recommended as a good description of Ni.
Here is a thread focused on the differences of Ne/Ni that has some good posts in it.
I hope this helps!
