Introverted Sensing (Si): 10 Signs and How to Develop Si

Introverted sensing (Si) is quite a paradox. It’s thought to be the most widely used cognitive function, yet it’s also arguably the most misunderstood one.

Many assume that Si simply makes people follow rules and traditions, but that’s a rather limited and simplified picture of this cognitive function.

In this article, we’ll explore introverted sensing (Si) to its core. Stick around and find out:

What is Introverted Sensing (Si)?
10 Tell-Tale Signs of Introverted Sensing Personalities
Introverted Sensing vs Extraverted Sensing: What are the Differences?
What Does an Unhealthy Si Look Like?
How Can Si Users Strengthen Their Introverted Sensing?

And much more!

Introverted sensing (Si) is a perceiving cognitive function that enables people to interpret the world by tapping into their past experiences and memories.

What makes introverted sensing so unique is the fact that people who use this cognitive function don’t simply see the world as it actually is. They filter it internally, comparing external data to their internal data, which often comes in the form of memories. As such, Si users have a subjective understanding of the environment based on personal impressions.

On top of that, Si users often use the past to predict the future. Knowing how something happened previously allows them to draw a direct comparison with what’s happening right now. Most importantly, this helps them not only to foresee what will happen in the future but also to change their behavior and achieve the desired outcome.

This way, introverted sensing is similar to introverted intuition (Ni). Moreover, both are subjective and aim to identify patterns and meanings. However, Ni is more concerned with finding hidden meanings, whereas Si seeks personal meaning.

Note: Check out extraverted intuition and compare it.

For example, if an object reminds Si users of some sweet memories, they’ll hold on to it dearly. But, if it reminds them of something bad, they’ll render it useless. Essentially, Si users attach associations to the things around them and derive value from subjective meaning.

Do you have trouble understanding how introverted sensing works in real life? Let’s take a look at how it shapes the personalities of the primary Si users—SJ (sensing judging) personality types.

ISTJ and ISFJ people use introverted sensing as their dominant function. Si makes ISJ personalities focus on the upkeep of their surroundings and personal well-being.

They take pride in caring for themselves and their environment, which makes them highly organized and well-put-together. They have high standards for their environment, appearance, and other areas. Moreover, they value comfort and things running smoothly but can get overwhelmed by unexpected changes.

What’s more, they’re often attached to objects that hold sentimental value for them. For example, they might hold onto an old pair of generic jeans because they wore them when they first met their significant other.

As auxiliary Si users, ESTJ and ESFJ personalities typically have a good grasp of introverted sensing. It supports their dominant cognitive functions— extraverted thinking (Te) in ESTJs, and extraverted feeling (Fe) in ESFJs.

As a general rule, ESTJs aren’t interested in experimenting. They tend to opt for traditional methods and solutions that have helped them or others in the past. Because of their auxiliary Si and focus on efficiency, they prefer to do things by the book, as this increases their chances of success.

ESFJs, on the other hand, can sometimes become preoccupied with other people and forget themselves. Auxiliary introverted sensing allows them to find a balance between nurturing other people and attending to their personal needs. This helps them live happier and healthier lives, as they don’t overextend themselves at the expense of their health.

Recognizing introverted sensing (Si) in yourself and others is easy when you know what to look for. So, let’s take a closer look at 10 classic signs that indicate strong Si users!

If there’s one thing that Si users can’t deal with, it’s discomfort. They typically place a high value on being comfortable, which makes them great at spotting opportunities to maximize comfort in their surroundings.

If you’re lying on a sofa, for example, they might bring you a pillow and a bed throw so that you feel warm and snug. This is also how most dominant Si users—who tend to be somewhat reserved—show love and care to people around them.

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Si users appreciate and strive for predictability in their lives. They love to start the day with the same morning routine and build positive habits to structure their days. As such, they usually have a methodical approach to life.

Interestingly, auxiliary Si users typically perfect routines to boost their productivity, whereas dominant Si users use them mainly to avoid chaos.

Since Si users aim for stability and predictability, it’s easy to guess that they aren’t open to change. In most cases, they find dealing with change extremely stressful, as it makes them feel out of control.

While they don’t like change, Si users might accept it if they feel it’s necessary or beneficial. For example, they may be against getting a new TV stand just so it fits with the interior of the room. However, they might become more open to the idea if they’re certain it’ll provide more storage space.

Most people with strong introverted sensing users have a talent for recalling memories in great detail. Music, food, smells, and similar things can easily trigger their memories and bring them back to the past.

Generally speaking, Si users’ memories are strongly attached to their emotions. As such, recollecting them allows them to experience the moment as if it’s happening right now. Their past experiences also influence the way they perceive what’s currently happening around them. For this reason, they deem memories important.

Si users are generally sentimental and prone to nostalgia. Although they may not want to admit it, this makes them rather romantic.

They love to surround themselves with things from the past that remind them of positive experiences. They often keep pictures of their loved ones in their wallets or set them as screensavers, hold onto their favorite childhood toys, collect memorabilia, and so on.

Introverted sensing allows people to learn from their mistakes and use their past experiences to improve the present.

Si users are careful about not making the same mistake over and over again. Some people might try and test their luck after failing the first time, but this isn’t the case with Si users. One bad experience is all it takes for them to reconsider their actions and choose a different path.

People with strong introverted sensing are practical and have a matter-of-fact approach to life. They value concrete, factual information over abstract ideas. Moreover, they don’t trust methods that have yet to stand the test of time.

Si users are only interested in theoretical concepts if they have real-world applications. For example, they may not be keen on discussing the differences between Taoism and Stoicism but might be inclined to learn music theory to master songwriting.

People with well-developed introverted sensing tend to be meticulous and detail-oriented. Like all sensing personalities, they are great at noticing details but might miss the big picture.

What’s more, they instinctively make comparisons between how things currently are and how they’ve always been. For this reason, they’re the first people to notice changes in their environment and other people’s behavior.

Si users are some of the most loyal and trustworthy people. They value actions more than words and make sure that their behavior aligns with their values and beliefs.

This consistency in their personalities makes them very dependable, both in their personal and professional lives. They’re realistic, down-to-earth, and certain about their abilities. As such, they don’t make sky-high promises that lead to disappointment.

Introverted sensing enables people to closely connect with their physicality. As such, they can easily tell when they’re hungry, thirsty, or tired and will immediately take action to take care of their needs.

Most Si users are health-conscious, so they make sure to go to sleep at a reasonable time, eat nutritious meals, and so on. They’re also concerned with the well-being of people close to them. So, if anyone asks you if you have eaten anything today, there’s a good chance you’re talking to a Si user!

Introverted sensing and extraverted sensing (Se) are both perceiving cognitive functions concerned with the physical world. Nonetheless, you may be surprised to know that they’re quite different!

Here are some of the main differences between Si and Se:

Objective vs. subjective reality. While Se users see the world for what it is, Si users perceive it through a subjective lens. Their perception of the world is strongly shaped by their impressions, past experiences, and other subjective factors.
Aesthetics vs. comfort. Se users care much more about looks than Si users. They’re more likely to follow fashion trends and buy things based on visual appeal. Si users, meanwhile, value comfort and functionality. They also know exactly what they like or dislike and often repurchase the same items.
Flexibility vs. control. Se users are spontaneous and prefer to leave their options open. Si users, on the other hand, like to be in control of situations. They like predictability, routine, and familiarity—all things that Se users get easily bored of.

Although SJ personalities are the most advanced and confident users of introverted sensing, this cognitive function also impacts other personality types. Here’s how:

Tertiary Si ( INTP, INFP). Developing tertiary Si helps INP types cope with stress by engaging with things (foods, music, movies, etc.) that remind them of positive memories.

Inferior Si ( ENTP, ENFP). Inferior Si enables ENP personalities to learn from their mistakes and become more sensible when pursuing new experiences.

Opposing role Si ( ESTP, ESFP). As their first shadow function, Si can make ESPs overly focused on details. This can make it difficult for them to move forward, as they don’t have much control over this function.

Critical parent Si ( ISTP, ISFP). Introverted sensing in the critical parent role can make ISPs judge themselves for repeating mistakes and not following through with plans.

Trickster Si ( ENTJ, ENFJ). With Si as their trickster function, ENJ personalities can become disorganized and messy. Alternatively, they may neglect their personal needs, especially if they fixate on their goals.

Demon Si ( INTJ, INFJ). Unhealthy INFJs and INTJs might dwell on regrets and be unnecessarily unkind to themselves for making mistakes.

Like all cognitive functions, introverted sensing is only advantageous if you’re using it healthily. Here are some signs of Si getting out of hand that you shouldn’t ignore:

Blindness to personal needs. Physiological needs, such as hunger, are the foundation of Maslow’s hierarchy of needs. As such, unhealthy Si can greatly diminish your overall quality of life by making you oblivious to your needs.
Excessive worrying about health. Alternatively, unhealthy introverted sensing can make you overly concerned with your mental and physical well-being. At worst, this can lead to hypochondria.
Preoccupation with the past. If you notice yourself idealizing and romanticizing the past, you may be experiencing unhealthy Si. Because of this, you may not be able to enjoy your life at the present moment.
Wallowing in mistakes. Since introverted sensing is closely related to the past, it typically helps people avoid making the same mistake twice. However, unhealthy Si can make you focus on regrets and past mistakes.

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All cognitive functions develop throughout people’s lives, and introverted sensing is no exception.

So, let’s see how Si shapes the behavior and characteristics of primary Si users during different personality development phases!

Dominant Si users—ISTJs and ISFJs—begin developing introverted sensing in childhood.

As children, ISJs are typically more interested in the real world than fiction. Many ISJ children prefer browsing encyclopedias to reading fairy tales. Similarly to Se users, they love exploring the world through their senses. However, they tend to be rather cautious, as they quickly learn what can bring them pain or discomfort.

ESTJs and ESFJs often start developing their auxiliary introverted sensing in childhood, but it doesn’t play an active role in their development until puberty.

ESJ personalities are prone to making quick judgments, which aren’t always correct. However, introverted sensing helps them see the consequences of their actions. So, once they start developing their Si, they typically learn to curb this tendency or at least keep it to themselves.

The third personality development phase is difficult to complete, to say the least. However, developing introverted sensing can help tertiary and inferior Si users—NP personality types—become more practical and driven.

Si enables intuitive perceivers to organize their thoughts and realize their true calling in life. With the help of Si, they learn to evaluate which opportunities are worth their time based on previous experiences.

On top of that, introverted sensing often brings them an awareness of how their choices affect their health, which can lead to positive lifestyle changes.

If you’re looking to develop your introverted sensing, you’re in luck! Si is one of the most enjoyable cognitive functions to work on.Si is one of the most enjoyable cognitive functions to work on.

Here are some easy but effective ways to strengthen your Si:

Remember your childhood favorites. Si users find comfort in things that are familiar to them and induce positive memories. So, watch Harry Potter movies, listen to N’Sync, eat Fruit Loops… or do anything else that reminds you of your best childhood moments.
Flip through pictures. Shake the dust off your photo albums and take a trip down memory lane! Or, if you don’t have any printed photos, scroll through your camera roll. In any case, try to recall your memories in detail to exercise your introverted sensing.introverted sensing.
Create a realistic daily routine.Introverted sensing thrives on predictability and structure. So, try to come up with a daily routine that you can easily follow for months—or even years—to come.
Deep clean your home. Chaos and mess are two things that don’t go well with introverted sensing. So, set aside a weekend to clean all the nooks and crannies in your house—yep, even the junk drawer!

That’s everything you need to know about introverted sensing!

We hope this article helped you realize there’s much more to this cognitive function than meets the eye. It’s deep and personal, which many personality typology enthusiasts find surprising, given that it’s a sensing function. But, interestingly enough, Si is much more similar to its cousin function—introverted intuition—than its sister Se!

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