Ne-Si makes connections easier than Si-Ne does. Like, from a young age, a high-up Ne user will figure stuff out that the Si-dom wouldn’t even notice. This isn’t a slight against the Si-doms, who can usually actually remember people’s names and maybe even where they parked in the lot five minutes ago, but Ne just… reads between the lines.
As a kid, I knew that Alfred Hitchcock movies were sly, sneaky, a bit kinky, and using double innuendos to get past the censors before I knew what sex even was; I just knew more was going on than was obvious, and that something weird and possibly “bad” (to my innocent little naive radar) was happening in the subtext. Subtext I didn’t even understand yet. I accurately guessed that a girl had been molested as a kid, based on a couple of random conversations that happened months apart and seemingly had no relation to one another, but my brain connected the pieces unconsciously. I was right, but it surprised everyone that at ten years old, I knew this from her parents not letting other siblings go on sleep-overs and being over-protective, and other things.
Now, in fairness, I know a Si-dom (ISTJ) who has an insane use of Ne. She can predict stuff better than I can and I think it’s because she has so much information and personal experiences stored in her head (Si) that her brain subconsciously connects pieces of information, weighs them against similar things that have happened in the past, and trusts that history will repeat itself. And a lot of the time, it does. It’s very much a Si-dominant Ne process, but I suspect it needs stuff to “connect to” in the first place (which, of course, being a Si-Te, she has because it’s all about BOOKS and LEARNING and USING STUFF), whereas mine doesn’t always need former references and instead, will go looking for validation on theories that come out of nowhere.
So I guess the primary difference is — Ne-Si makes crap up that is often right, but then goes looking for proof of it; Si-Ne knows the truth from previous experience.
Not sure how anyone could confuse Si-dom for Ni-dom, because Si-doms are all about concretes and details and repetition and handling the everyday essentials inside a comfortable, reliable routine, whereas Ni-doms are all about big picture visualization and new concepts, and pooh on routine (routine is boring!!), while steadily working toward implementing their inner vision in some way; but I can see how Ni can get confused for Ne, because they both do the same thing in some regards (predictions, “knowing things,” etc), while being very different. Ni-doms, as I have said repeatedly over the last few days, are very much into in-depth symbolism and visualization. Ni goes deep. Really deep into a topic. Deeper than anyone else anticipates, and then it goes back for more. It will be content to re-examine something it values for decades, because there is always another layer of truth to unearth.
Ne is not like this. Ne gets bored with something it has already figured out, and wants to find something new to learn and focus on for awhile. Let’s say that Ni and Ne are both into The Lord of the Rings. Ni will go back, again and again, finding something new and exciting in the series each time. The obsession lasts decades, if not their entire life. Now, the Ne user gets obsessed for awhile, tears it apart, reads the books, watches the movies, discusses it from every angle and… are done.* They will revisit the series now and again, but never with the same level of ferocity and intensity, because in their mind, they understand it, they have seen it, they have explored it, and there probably isn’t any new angle left to discover. It’s an old passion, not dormant but waiting for a new tidbit to add to their knowledge base. Until that arrives, and sheds an entirely new light on Middle-earth, it’s an old hobby like so many, that has a special place in their heart but no longer holds their intense focus. Been there, done that, what’s next?
Of course, Ni has Se, which is factual retention and memories, but without the desire for routine and tendency to relive emotional experiences of Si. So INXJs will not fall into a melancholic memory rut in the way that Si-users of any kind do; Si is subjective memory, influenced by personal values and opinions, but also brings with it access to those same feelings it had when the incident happened. Se is objective, impartial memory retention, which allows Ni to evade the emotional baggage. It wants new experiences merely for the experience itself, whereas Si wants to hold on, in some respects, to the past and routine for its own comfort and state of mind.
* True story. Me and my NJ friends. Heh.
ETA: I should probably mention that Si-doms love LotR too, and will return to it, but their enjoyment is different from Ni. They’re reliving something they loved, and have subsequently loved ever since; each time they watch it, it is solidified in their minds as “awesome.” Si brings back a host of memories of previous experiences watching it, and… you guessed it, the same emotions revisit them each time.