The INTJ personality type’s signature strength is deep perception. Otherwise known as “The Mastermind,” the INTJ is naturally attuned to the big picture and can’t help but see how everything is interconnected. Their ability to perceive deep patterns and causal relationships has helped many achieve eminence in science, mathematics, medicine, and other INTJ careers.
Although INTJs are classified as Thinking types, their dominant function is Intuition, or more specifically, Introverted Intuition (Ni). In seeing the world through Ni lenses, their typical mode of operation is well described as impressionistic. Rather than noticing or concerning themselves with the details of the world around them, their existence is more cerebral or dreamlike. This can lead them to feel estranged from their physical environs, not to mention their own bodies.
While INTJs may be relatively unaware of how others perceive them, their “other-worldliness” often earns them labels such as quirky, awkward, nerdy, or oblivious. Onlookers sense that INTJs seem to “live in their own world.” Immersed in their own minds and interests, INTJs can be oblivious to social norms or other practical aspects of life. While incredibly “book smart,” they may fall short when it comes to social or “street smarts.”
At some point in their lives, INTJs start to notice how characteristically different their personality traits are from those of their peers. They may even joke about the nerdy or esoteric nature of their interests. Fortunately, they usually find a few friends with overlapping interests, even if those friendships are largely maintained through what others might consider non-social activities, such as playing video games over the internet.
Further complicating INTJs’ social life is their use of Extraverted Thinking (Te). The majority of males, at least in the United States, are TP types, all of who use Extraverted Feeling (Fe) rather than Te. This gives TPs (including the INTP) a leg up when it comes to casually connecting with others in social situations. TPs often enjoy social situations (at least for a stint), which grant them opportunities to showcase or sharpen their social chops. By contrast, INTJs, along with other Te types, often loathe unfamiliar social situations. They find it painfully difficult to “rub elbows” or engage in any measure of “small talk” with strangers. This further intensifies their sense of being “different” from their peers.
INTJ Personality Traits
INTJs are characterized by a curious admixture of personality traits which includes their reputation for being “walking encyclopedias.” They are sponges for all sorts of information, be it historical, scientific, technical, or otherwise. I’ve met many INTJs who seem to have “photographic memories,” able to recall nearly anything they’ve been exposed to. One of my INTJ friends, for instance, can readily recite lines from movies he’s only watched once.
In recognizing their powers of insight (Ni), not to mention their vast stores of factual knowledge (Te), INTJs are naturally inclined to share what they know with others. In addition to activities such as gaming, dispensing ideas or information is one of the easiest ways for INTJs to engage with others. They enjoy opportunities to utilize their typological strengths and enlighten others. Unfortunately, this can sometimes result in INTJs being misconstrued as arrogant “know-it-alls.”
Despite their introverted status, INTJs can be surprisingly talkative. Like the INFJ, they can talk at great length (and depth) on topics that interest them. This is one reason INTJs often enjoy the role of lecturer or professor. And while they are rarely the most dynamic or energetic of orators, INTJs are typically decent story-tellers and good for occasional injections of droll humor or cultural references. This can help humanize them in the eyes of their audience, even if their overall delivery remains a bit dry or mechanical.
Because INTJs extravert their Thinking judgments (i.e., Te), others commonly (and often wrongly) assume them to be characteristically serious individuals. This misses the fact that they are dominant Perceivers (i.e., their dominant Ni function is a Perceiving function), which makes them far more inwardly easygoing, even playful, than most people realize. I’ve known some INTJs who begin every day with comedy, such as catching up on the latest online memes. This is one reason type theory is so important: it keys us into inner (I) – outer (E) type differences that might otherwise be overlooked.
Another consequence of INTJs’ Perceiving dominance is their tendency to be passive or phlegmatic. More proactive types, such as ENTJs, might even consider them a bit lazy or apathetic. But calling INTJs lazy is to miss the point of what it means to be a Perceiver. Namely, since INTJs’ first and foremost job is to Perceive rather than Judge or act, functioning in a passive mode of perception is actually their most authentic mode of operating. Indeed, the reason that INTJs’ theories and insights are often superior is because they do not force things. They patiently allow their Ni intuition to collect and synthesize all the pertinent information before they draw conclusions. Again, others may be blinded to this reality if they focus exclusively on INTJs’ external presentation.
INTJ Type Development & Function Stack
Each personality type prefers to use four of the eight functions first described by Jung. These four functions comprise a type’s “function stack.” The relative strength of preference for these four functions is expressed in the following manner: dominant, auxiliary, tertiary, and inferior. INTJs’ first preference is Ni, followed by Te, Fi and Se respectively. This is depicted in the arrangement of their function stack:
While we will soon discuss each of these functions in greater depth, for now, we will turn our attention to another feature of INTJs’ personality—their type development. As is true for all the personality types, INTJs’ type development consists of three general phases. These phases roughly correspond to the ordering of the function stack, with Ni being the first function to blossom, Te the second, on so on. But as we will see, the inferior function is sort of a special case, summoning INTJs’ attention at an earlier phase than might otherwise be expected.
Phase I (Childhood)
Early in life, Introverted Intuition (Ni) emerges as INTJs’ dominant function. The degree to which the dominant function needs to be worked on or developed is not entirely clear. If one can argue, for instance, that great athletes are born not made, might the same not be true for a type’s dominant function?
Regardless, INTJs’ amass a great deal of information for their Ni to chew on throughout their childhood. The longer they live and the more they see, the more their worldview crystallizes and the more confident they feel in their understanding of things. Even young INTJs are keen to understand what is happening around them. This is what Ni does. It looks beyond appearances to discern the root causes and structures of things.
But as we’ve seen, INTJs aren’t always all that serious-minded. Many spend their childhood playing video games, watching movies, learning an instrument, or surfing the web. They acquire much of their knowledge through happenstance, without much in the way of conscious effort.
Phase II (Adolescence-30s)
In Phase II, their inferior function, Extraverted Sensing (Se), begins to assert itself and to play a more prominent role in INTJs’ psychic drama. The inferior’s undue influence can be seen as stemming from its bipolar relationship with the dominant function. Namely, in order to ensure psychological diversity or balance in their personality traits, INTJs feel compelled to experience something characteristically distinct from the dominant function. The inferior function is often experienced as magical, mysterious, and exciting, even blissful. Some have described it as “a whole new world.” It can thereby serve as a powerful source of energy and motivation. This is why all types, especially those in Phase II, display a strong appetite for, and curiosity toward, their inferior function.
As will be enumerated in our forthcoming section on Se, the emergence of Se may take the form of INTJs’ showing greater interest in novel aesthetic or sensory (S) experiences. While INTJ children are often leery of new experiences, as time goes on, they may gradually open themselves to S novelties. Although INTJs tend not to be as “experimental” in their approach to life as NPs, many come to welcome new S experiences as an invigorating alternative to their typical state of NT cerebralism.
Because of its deep allure and sense of novelty, the inferior can lead INTJs, to make questionable career or relationship decisions in Phase II (see my INTJ relationships post). It may, for instance, cause them to pair with incompatible types under the spell of the “opposites attract” (i.e., inferior function attraction) phenomenon. Therefore, Phase II INTJs can typically benefit from a reality check, remembering that their “core self” is ultimately founded on their Ni, not Se.
The siren call of the inferior function can be effectively counterbalanced by regular use and development of the auxiliary function. For the INTJ, this means bringing a greater measure of Te to the proverbial table. Te helps INTJs rationally explicate their intuitions, whether in math, science, consulting, or related fields. Regular employment of Te also encourages INTJs to move out of Perceiving mode and into Judging, promoting a more diverse and balanced personality.
Phase III (30s, 40s, & Beyond)
Phase III INTJs wise up to the tricks and temptations of the inferior function, discovering more sustainable ways of integrating their functions. Rather than leapfrogging between the dominant and inferior functions (e.g., the bipolar behavior characteristic of Phase II), they learn to stay grounded in their Ni as they explore, develop, and integrate their less conscious functions.
INTJs in Phase III also become skilled in achieving what psychologist Mihály Csíkszentmihályi has dubbed the “flow state.” Flow states are characterized by deep absorption in an activity, an optimal balance of challenge and stimulation, and a sense of progress toward a meaningful goal. In a state of flow, INTJs forget about themselves and their concerns, “becoming one with” the activity. Flow states are most likely to emerge when INTJs perform activities that engage their dominant and auxiliary functions. For more on this, see my book, The 16 Personality Types.
INTJs’ Dominant Function: Introverted Intuition
As we saw earlier, in order to best understand INTJs, we must recognize the full implications of their dominant function, Ni, being a Perceiving function. While INTJs can certainly function as rational thinkers via their auxiliary Te, their first preference is to process matters in less rational ways a la Ni.
In its popular connotation, intuition is understood as an unconscious way of knowing, or what writer Malcolm Gladwell has cleverly described as “thinking without thinking.” It is therefore interesting to consider that, for dominant Intuitives such as INTJs, intuition is understood to be their most conscious function. While it is true that intuition is more conscious for INTJs than it is for other types, we must remember that Ni is a Perceiving function. So although INTJs may have readier access to its workings and products, there is still a sense in which they don’t really control it. Intuitive insight often seems to emerge ex nihilo, as a welcomed but unexpected gift from the muses.
With that said, INTJs do possess some measure of control over the types of problems they want their Ni to solve, not to mention the raw material they feed into it. The more they immerse themselves in a certain problem or subject matter, the more their insight will deepen. So it’s not that INTJs can be totally hands-off and allow Ni to do all the heavy lifting for them. Healthy INTJs find the right balance between allowing their Ni to do its thing and consciously participating with the process.
Because of its prescience and depth of insight, Ni may at times seem to border on magical or supernatural. While not discounting it impressiveness, the Ni process can, at least to some extent, be rationally explicated. Namely, INTJs’ inferior function, Extraverted Sensing (Se), unconsciously collects vast quantities of sensory information from the outside world. This data is then kindly forwarded to Ni, which tries to make sense of it, like assembling the pieces of a puzzle. Eventually, an impression is formed that reveals the deeper reality or N pattern behind the data.
It is often said that human beings rely more heavily on vision than their other senses. This seems particularly true of INJ types, who often associate a strong visual element with their Ni. Many report thinking by way of images more than words. Their intuitions may take the form of symbols, images, dreams, or patterns. This is consistent with Jung’s characterization of the Ni type as the dreamer or seer. There is a distinct visual character to these notions, which is why vision-related terms—foresight, insight, seer, visionary, etc.—are commonly ascribed to INJs.
Visual processing may prove advantageous for solving problems that seem resistant to rational solutions. This is because visual processing isn’t bound by the same rules or limitations as verbal or logical processing. Indeed, Ni’s unique approach to problem-solving may explain why INTJs often make such formidable analysts and theorists.
INTJs’ Auxiliary Function: Extraverted Thinking
While Ni is a holistic and synthesizing function, INTJs’ auxiliary function, Te, hails squarely from the left side of the brain. The left hemisphere is characteristically logical, analytical, and systematic. It breaks things down into their constituent parts, explicates their roles, and maps their relationships to other parts.
A Te-based approach also emphasizes quantification, as well as the establishment of measurable goals and standards. Never vague or ambiguous, it employs clear definitions, policies, plans, and procedures. It carefully spells out how to get from here to there, using as many maps, directions, and labels as necessary. The ultimate goal of Te is to render things logically intelligible, making them more amenable to human manipulation, prediction, and control.
Ni is neither characteristically rational nor highly systematic. Only the Judging functions, most notably Te, operate in such a fashion. And because Ni comes first in INTJs’ function stack, Te is ultimately more of a servant than a master. It is primarily used to analyze or flesh out Ni’s intuitions. Once an intuition has formed, Te takes the reins and works to give it rational form, sort of like decompressing a computer file. Te’s ability to translate intuitions into words, diagrams, or formulae is important because it helps others better comprehend INTJs’ insights.
In explicating their intuitions, Te is highly systematic and methodical, even perfectionistic. INTJs pay close attention to the way things are ordered, ensuring that their work follows the appropriate linear or logical sequencing. They may also work to incorporate relevant Te facts, data, and other objective considerations.
With that said, INTJs always keep at least one eye on the bigger picture, ensuring that they are staying true to their foundational intuition. This is one way INTJs differ from SJ types, who often miss the bigger picture or end up getting lost in the particulars. Not only are INTJs blessed with the ability to isolate and analyze specifics, but they simultaneously maintain a clear vision of the whole system, including its hierarchical structure and the interrelationships of its component parts.
The fact that INTJs lead with Ni rather than Te also casts doubt on perceptions of INTJs being excessively stubborn or closed-minded. Such perceptions are typically rooted in observations of INTJs’ extraversion of Thinking. But because Te closure is not their typical or preferred state of being, we should be careful not to confuse their outer presentation (Te) with their inner reality (Ni). INTJs are far more open inwardly than they may seem outwardly.
Another feature of Te, which we touched on earlier, is its social presentation. Unlike Fe, Te is not concerned with procuring social harmony or group morale. It is characteristically impersonal—focused on facts, objects, and systems rather than feelings. The inability of others to approach things impersonally or objectively is a common point of frustration for INTJs. They may feel incredulous toward others’ repeated failure to see, and/or appropriately respond to, objective truth. INTJs often feel that, regardless of how sound their arguments or the amount of evidence they present, some people simply won’t budge. Even more frustrating is when they see those same people responding to F influences. When this happens repeatedly, INTJs may become dismayed or nihilistic, concerned that humanity will forever remain blind to the truth.
One can see this playing out in the political careers of INTJs Hillary Clinton and Al Gore. Both are among the most intelligent of politicians, possessing a solid understanding of national and global dynamics. But both are/were plagued by a lack of charisma and likeability (i.e., a lack of Fe), making it difficult for them to inspire or connect with others on an emotional level.
INTJs’ Tertiary Function: Introverted Feeling
Despite their preference for Te over Fi, it would be a mistake to assume that INTJs are emotionless robots. The real difficulty for INTJs is that, regardless of how strong their emotions or convictions may be, this often gets lost in translation. We know that INTJs’ feelings don’t readily translate because their preferred Feeling function (Fi) is introverted in its direction. Instead of extraverting Feeling, they extravert Thinking (Te). This precludes others from readily accessing their emotional state. Instead of seeing variations of expression or intonation (Fe), one encounters a relatively flat, monochromatic presentation (Te).
With respect to other people, Fi is associated with intensive emotional investments in a limited number of individuals. Instead of distributing its emotional energies broadly in the way of Fe, Fi is more focused and discriminating. This is why INTJs typically show little interest in social networking. Instead, they typically invest themselves emotionally in their families, along with one or two close friends. They tend to be loyal and committed partners, as well as unswervingly devoted to the well-being of their children. While they may be skeptical toward a great many things, the value of family and friendship is typically not one of them.
Career-wise, Fi may inspire INTJs to work toward social change and reform, be it in business, politics, economics, education, or otherwise. Fi is highly sensitive to injustices, especially those affecting individuals perceived to be incapable of helping or defending themselves (e.g., children, the elderly, the poor, etc.). Hence, INTJs’ Fi often teams up with Ni to foresee paths to a more just and equitable world. Te may also play a role in the process, such as developing strategic or logistical plans for reforming broken systems. This combination of Ni, Te, and Fi explains why INTJs often score high on the Enneagram’s type One, often called “The Reformer.”
With that said, I’ve observed a fair amount of variability among INTJs with respect to the prominence of Fi in their personality. I know one INTJ, for instance, who had a rather difficult upbringing and has spent most of his adult life trying to understand and remediate his childhood wounds. This led him to develop interests in both normal and abnormal psychology. I’ve also known INTJs who show little more than a passing interest in psychology. It may be that differences in childhood experiences affect the degree to which INTJs focus on Fi matters, including their own emotional landscape. The interaction of nature and nurture may also affect the degree of INTJs’ emotional stability. Some INTJs are emotionally labile and constantly turning to others for support. Other INTJs are characteristically more steady and independent in handling their emotions.
The last thing I’ll mention about INTJs’ Fi is its contribution to their interest in self-knowledge, including their desire to understand what makes them unique and different. For quite some time, I was perplexed as to why so many INTJs took interest in personality typology. I hypothesized that in most cases it was probably career-related, such as trying to match their personality to a particular career field. I later realized that their reasons often ran deeper than that. Namely, similar to what we see in FP types, INTJs’ Fi compels them to understand who they are as unique individuals.
INTJs’ Inferior Function: Extraverted Sensing
The importance of the inferior function has long been grossly underestimated in the type community. Sometimes called the lost, missing, or repressed function, it is the most unconscious of the four functions. It is also the most difficult to access, understand, and integrate. Despite its relative elusiveness, we should be careful not to dismiss it as irrelevant or unimportant, as has too often been done. The truth is that a proper understanding of the inferior function is indispensable in the human quest for wholeness and integration.
As is the case with other types, INTJs display a “love-hate” relationship with their inferior function, Extraverted Sensing (Se). This is especially true for those in Phase II of type development. Fortunately, the challenges associated with the inferior can be largely offset by understanding its essential nature, as well as potential ways of integrating it.
Generally speaking, having Se as their inferior function makes INTJs less attuned to the details or concrete elements of life. While Se takes in plenty of sensory data from the outside world, what INTJs typically experience is an Ni synthesis of that information. So instead of registering particular environmental details (Se), they see the world through the lens of Ni impressions. They can therefore seem rather oblivious to the details of their surroundings.
This is not to say, however, that INTJs are unaffected by, or insensitive to, their physical environment. Although they may be consciously oblivious to their surroundings, they are still absorbing and subconsciously registering a breadth of environmental stimuli. Similar to INFJs, their nervous systems are often highly permeable and sensitive to the environment. This is why they commonly know things without realizing how they came to know them. They passively absorb information apart from conscious effort. This permeability can also make them susceptible to overstimulation in noisy or chaotic circumstances.
Because of their conscious disconnect from the world around them, many INTJs report feeling like aliens or strangers in the world, even estranged from their own bodies. This can make them leery of unfamiliar S experiences, such as trying new foods, drugs, or physical activities. Doing so can seem too risky or unpredictable, since the S world seems largely outside of INTJs’ sphere of control.
In time, however, INTJs may gradually become more open to and interested in S novelties. Those intrigued by their inferior Se may display a surprising thirst for sensory novelty, material comforts, or physical thrills. They may drive expensive cars, purchase luxurious homes, or opt for high-end accommodations when travelling. Some even become connoisseurs of fine food, wine, or art.
This points to the love-hate relationship INTJs often have with their inferior function. Depending on time and circumstances, Se matters may be viewed as a source of great pleasure and intrigue, or one of fear, stress, and frustration.
Both INTJs and INFJs are notorious for their predilection for perfectionism. Fortunately, this propensity is well-explained by type theory. Namely, INJs can be understood as striving to integrate their dominant Ni with their inferior Se, to see their N ideals perfectly materialized in S reality.
Parenthetically, while it is true that ENPs also have a dominant N (i.e., Ne) and inferior S (i.e., Si) function, Ne tends not to get attached to a single vision in the way that Ni does. Where Ne is open to multiple interpretations or possibilities, Ni sees only one. So although some ENPs can be perfectionists (Steve Jobs is a good example), perfectionism is a more consistent and signature tendency of INJs.
For instance, one of my INTJ friends spent well over a month working to resolve a problem with the rendering of bullet points in his business’s email newsletters. Despite the fact that the problem would only be noticeable to about 10% of his email clientele, not to mention that it was considered intractable by many email experts, he continued to relentlessly pursue a solution. Ultimately, after many weeks of work and frustration, he managed to find his own workaround.
As suggested by this example, perfectionism, thoroughness, and perseverance (or what some might call obsessiveness or compulsiveness) are closely linked for INTJs. Many feel they cannot rest or move forward until certain foundational matters have been squared away. While other types might content themselves with “good enough,” INTJs are insistent that their work meets their own (often very high) standards of excellence.
Learn More in Our Books:
Learn more about INTJs—their personality, cognition, career roles, life struggles, paths to growth, and more—in our books:
INTJ Famous People / Celebrities:
Stephen Hawking, John Nash, Al Gore, Jean-Paul Sartre, Mary Poppins, Dr. House (television), Ayn Rand, Hillary Clinton, Monk (television), Daniel Quinn, Sherlock (television), Sam Harris, Isaac Newton, Dita Von Teese, Anna Wintour, Elon Musk.
*INTJs may find some points of overlap with the Enneagram 5 (5w4, 5w6) and Enneagram 1 (1w9, 1w2).