Si vs. Ni: 5 Main Differences

It would be really easy to start talking about the stereotypical differences of Ni vs Si: how Ni users are the visionaries and Si users are the traditionalists as many articles do, but both of these statements would be misleading. Sure, Ni users will have a vision for their own personal future, but that’s a far cry from being a visionary. After all, the average high Ni user doesn’t produce some global, earth shattering vision of how they can solve all of mankind’s problems. That’s clearly unrealistic. Likewise, the Si users aren’t always steeped in traditions and repeating the past. Sometimes they’re avoiding repeating the past at all costs. It just depends on how events in their life actually unfolded. So, I’m going to bring up the key differences as dictated by the cognitive functions, and explain what they mean in a practical, real life setting.

The 5 Main Differences

1. Si users have a detailed sensory-based memories, while Ni users have impressionistic memories

This is the most important concept for you to grasp in this entire article. This is the root of Ni and Si. If you really think about this point and really dwell on the implications of it, you will be able to understand where every stereotype, misconception, and description of Ni/Si actually comes from.

Si users introvert concrete, sensory data. When they look into the past, they’ll remember how something physically felt (but not necessarily emotions), smelled, looked, and etc. They’ll remember odd and possibly mundane details that people may be surprised that they remember. This is probably one of the easiest cognitive functions to understand. When Si users search their memories, they’re looking to match up the present details with the past details. Ni users are the opposite.

Ni users store away memories in the form of impressions. Sure, everyone remembers details to a degree, but Ni users are going to hone in less on those details. Sure, they’ll notice details in the moment, but they’re going to focus more on the overall idea of what just happened and store that away. They’re more interested in the lesson or meaning behind something. Essentially, they’re introverting information to be used for pattern recognition later. Ergo, while Si users are matching up details with details, Ni users are comparing present patterns with past patterns. This is why Si conclusions are frequently traceable to specific memories, while Ni conclusions can appear to be without backing.

I’ve also covered this subject a decent amount here.

2. Si users lean heavily on past experience, while Ni users are guided by intuition

Because Si users store away the past in great detail, they will lean heavily on that vast store of information in their head. This does NOT mean they will mindlessly repeat traditions. They’ll repeat the good, but avoid the bad. If something has always worked, they’ll keep doing it that way, and usually won’t feel the need to explore some new method of doing it, unless there is a very clear indication that the new way will be better. On the flip side, if something didn’t work, they will NOT do it again. They’ll excel at learning from the past. Therefore, with all that said, the ISXJs will feel very uncertain and hesitant when they have no experience to match up to the current situation since they rely on their past experiences. They’ll probably try to gather information from others, effectively trying to learn from other people’s experiences, since they have none of their own. Both ISXJs and ESXJs may appear very future oriented in an attempt to plan out the best path to reach their desired life goal. ESXJs will be more impulsive or eager to try something new than ISXJs since their dominant function is extraverted, but they’re unlikely to be as impulsive as the ENXJs due to lack of Se.

Ni users are the opposite. Their memory is abstract, more akin to a blurred photo. They’re not seeing the past in high definition like the Si users. Instead, they’re seeing the patterns, the big picture , or the end result. Pattern recognition is a much “quicker” type of memory, because it doesn’t require time to sift through all of the individual details to find the best matching memory. Rather, Ni users will somewhat regularly walk into a situation and recognize it without any explanation as to why. They will then respond based on these instincts. Because of the abstract nature of their memory, they’ll grow accustomed to acting in spite of the absence of clear information. Ergo, Ni users will be more comfortable operating in situations where they don’t have concrete information to dictate their next decision or action. Bear in mind, that Ni users can store away inaccurate impressions and inadvertently feed themselves bad information. While Si users can place too great an emphasis on irrelevant details, Ni users may lean heavily on a feeling or instinct that turns out to be based on a flawed memory or false impression. Regardless, using their intuition as a guide, Ni users will seek out the best path possible to achieve whatever personal vision or life goals they have formed.

3. Si users are more prone to being haunted by the past, while Ni users will view the past more objectively

I almost blended this point into the previous one, but then realized it warranted its own section. It’s relatively straightforward if you take into account everything I’ve said thus far. On a practical level, everyone can have a tragic past, and anyone with a tragic past will be greatly affected by it, no matter what their personality type. (Be very careful typing someone as an Si user if they legitimately have a tragic past – the trauma resulting from their past cannot be your primary reasoning.) However, as a general rule, Si users will remember their past more intimately. They’ll remember how something physically felt and all the individual, painful (or pleasant) details surrounding it. A negative past experience will leave a very bad taste in the Si user’s mouth, and Si users will very purposefully avoid repeating any scenario that went sour. For instance, dominant Si users are the types who may avoid a restaurant that’s typically good because of one bad or disappointing meal.

Ni users don’t intentionally reference the past often, especially younger ones. Taking that into account and their tendency to not remember a lot of intimate sensory information, they’ll view their memories and past in a more detached way. Obviously, Ni users can be haunted by their past. Anyone can. However, the average Ni user will simply view the past as the past, over and done with. They’ll prefer to look to the future, rather than glance backwards. However, when they decide to recount their past, they will probably do it in a more factual manner, rather than a personal reliving of the events. (Obviously, an introvert or distrustful personality won’t be quick to share their past with others, but this is all assuming they’ve decided to discuss their past with someone they trust.) The bottom line is that an Ni user won’t be reliving the past through their memories as strongly as an Si user would be, which will make it easier for them to generally explain what happened. The benefit of a less detailed memory is that it is not tied as closely to emotions.

4. Si users make concrete observations, while Ni users read between the lines

Si users prefer to take things at face value. They’ll be the people who get caught up on semantics and what exactly was said. They’ll pick up on your facial expressions, the details of the the rooms, and etc. and use this information to form a conclusion. When they make insightful observations, they’ll typically know exactly where they obtained the information that lead to their conclusion. It’ll usually be very clear cut and easy for them to explain. Please realize that Si users can be just as insightful as Ni users. It’ll just be less out of no where, ergo, seemingly less “magical.”

Ni users will be more about reading the meaning behind the words, rather than taking the words at face value. Ni users will probably get frustrated with semantics because they honed in on what the person meant, rather than what they actually said. They won’t always consciously pick up on expressions, and details and etc. Their Se will be working in the background to do this. Sure, they may notice that information in the moment, but they probably won’t remember a lot of it later. Because Ni users are subconsciously reading the room and comparing it to patterns from their past, they’ll be relatively confident making/sharing observations based on their intuition or gut.

5. Si users have an eye for the details, while Ni users focus on the big picture

Si users tend to be very meticulous and methodical. Si users have a tendency to take notes and write things down so they can repeat processes correctly in the future. They tend to be good at memorization. They’ll also be the ones that reference the manual, books, instructions, recipes, and etc. Si users in leadership will probably want their subordinates to complete their tasks in a very specific way. The ISXJs are the “slow and steady” people who will make sure whatever they do gets done right the first time. The ESXJs will be the micromanagers who make sure everyone does their task precisely to the ESXJs liking. Si users will also probably share information in a very detailed manner (since they typically have a vast store of information within their head), and they’ll expect detailed and relevant information in return. They won’t be comfortable with vague responses.

Ni users are more interested in the big picture or the broadest perspective possible. They’ll tend to be interested in hearing other people’s perspectives in order to gain a better overall understanding. They’ll also prefer concepts and tend to visualize things in their mind, rather than writing a lot down. They’ll need to understand “why” or the meaning behind something. They’ll prefer a bit less rigidness in their work environment so they can have freedom to complete tasks in the way they desire to. Likewise, Ni users in leadership will be less interested in how something was done, just as long as the desired result was achieved. In conversation, Ni users may feel impatient with people who take too long to get to the point. They’ll be more interested in hearing the point first and then all of the supporting information.

In Conclusion…

I hope this makes sense. I tried to split it up in the most understandable way possible, but I feel like some of the categories may have blended a bit. I apologize if that’s the case. Feel free to ask for any further clarifications.