Hello, this is my first thread on this website, but I'm just going to get straight to the point. For quite some time now I've found most descriptions of Ne and Ni to be rather useless since they more or less just say the same things. Both functions notice patterns, make connections, dig deep into ideas, and make predictions. This is simply an intuition thing and isn't unique to either function. I think in order to properly differentiate the functions, it is vital to consider the difference in focus the two functions have. This is just a hypothesis, so I would like some constructive feedback on any potential shortcomings in my descriptions.
To put it simply, I'm arguing that Ni is primarily focused on finding deep insights, while Ne is focused on finding all of the things that connect to a singular insight. Both functions will do things like draw connections, but I think the motivation behind finding said connections is what makes the difference. I speculate that Ne makes connections between ideas simply because it likes to see how many ways a single principle is/can be applied and enjoys seeing the connections between these things simply because it is fun. Ne may go back and think about the underlying mechanism or meaning behind an idea, but only so it can find more situations where that insight also applies. I think this is supported by the fact that dominant or auxiliary Ne is always paired with a dominant or auxiliary introverted judging function. When Ne finds more ideas that stem from a single insight, Ti or Fi can spend more time playing with those ideas and coming to decisions about them internally. I believe for Ni it is the opposite. Ni may bounce around from idea to idea, but it only does that as a means to an end. For Ni, bouncing around from idea to idea, or from observation to observation, only matters insofar as it leads to the production of one deep, original insight that can be acted upon. If the upper Ni user can glean a mind blowing insight from a single observation they will be more than satisfied with that, whereas the Ne user will only care about gleaning a powerful insight if it allows them to spend time finding more tangentially related ideas to think about. I think upper Ni is helped in this matter by the fact that it is always paired with a dom or aux extraverted judging function. Ni will glean an incredible insight about some system, which will then energize the Ni user, and inspire them to take action with Fe or Te.
To illustrate how I think this might play out in a real example, I'll use something I commonly observe in myself. I'm fairly certain I'm an INTJ, and I find alot of joy in coming up with novel ways to solve problems in mathematics and physics. However, my way of going about it is rather formulaic, I've come to notice. 1. analyze problem 2. Develop hypothesis on how to solve said problem based on some inexplicable realization 3. See if hypothesis is valid 4. repeat process if invalid, move on if valid.... I'm entirely satisfied with coming up with a single original way to solve the problem. Even if there are other ways to solve it, I'll only consider spending a lot of time thinking about them if my own method turns out to be inefficient. I imagine a high Ne user would be more likely to think about how to solve the problem in every conceivable way just for the fun of it, before moving on when they finally run out of potential methods. They might look at the method derived by the Ni user only because it might help them to think about other ways to accomplish the same result.
I suspect this has a lot to do with the stereotypical INTJ scientist classification. It's a description of how Ni and Te work together to come up with hypotheses and make plans to verify or falsify them. I'd be willing to wager it's much the same for INFJs, ENTJs, and ENFJs. Basically I look at it like this: Ne and Ni are both both circles of data points orbiting one central idea like a ring of stones around the larger boulder they broke off from. Ni will analyze the rocks on the out side, but only to learn what they want about the boulder on the inside, so they can act on their insights. Ne will analyze every rock around the boulder and will sometimes return to study the boulder on the inside, but only so they can see if they may have missed some other rocks on the outside that may have broken off of it.
Tl;dr Ni works by connecting ideas, noticing patterns, changing perspectives, etc, etc, but only so it can gain some crucial deep insight that Te or Fe can verify and act upon. Ne works by noticing patterns, gaining insights, changing perspectives, etc, etc, but only so it can find more emergent possibilities and ideas that Fi and Ti can play with.
Tell me if I'm off base.