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The ISTJ personality type is one of the most common in the US. If you aren’t an ISTJ yourself, you definitely have one at your workplace, among your friends, or in your family. INTJs, on the other hand, are a relatively rare type and may be difficult to understand.
So how can these two personality types be so similar yet very different? First, let’s examine the differences between ISTJ vs. INTJ.
What Is the ISTJ Personality Type?
An ISTJ is known as the Inspector, a practical, organized personality who values loyalty and tradition. They create order and structure wherever they go and have a procedure for everything they do. Key characteristics of this personality type are:
Introverted
The first preference indicates where people tend to direct and receive their energy. Introverts prefer to channel their energy inward toward ideas, information, and beliefs.
Introverts prefer doing things alone or with just one or two people they know and trust. Introverts usually think and plan before they act or speak and sometimes like the idea of something better than the thing itself.
Sensing
The second psychological preference indicates the way a person prefers to receive information. A sensing person pays attention to the information they receive through their five sense: taste, touch, smell, sight, and hearing.
They focus best on what is present, current, and real, noticing actual facts and remembering concrete details. They understand the practical use of things and learn through hands-on experience.
Thinking
The third preference indicates the way a person prefers to make decisions. A thinking person makes decisions based on facts and data, striving for objectivity. They try to reach conclusions that are universally applicable and useful all the time in every similar situation. They look for fundamental truths, underlying principles, and consistent practices without personal influence.
Judging
The final preference indicator refers to how a person deals with the outside world. For example, a person with a judging personality prefers a structured life, concrete plans, and firm decisions. They make step-by-step plans, keep to-do lists and schedules, and exercise control over their life and time.
The ISTJ is most comfortable in an orderly system with consistent rules and procedures. The Inspector is loyal and faithful, upholding and protecting laws and traditions and defending their friends and family.
They are patient, persistent, and detail-oriented, capable of making long-term plans and following them meticulously every step. The ISTJ is incredibly reliable, dutiful, and responsible. They are calm, level-headed, and practical, and there is no one you would rather have at your side in a crisis.
What Is the INTJ Personality Type?
The INTJ personality type is known as the Architect for their ability to combine rational strategy with creativity. Their key characteristics are:
Introverted
The first preference indicates where people tend to direct and receive their energy. Introverts prefer to channel their energy inwards toward ideas, information, and beliefs.
Introverts prefer doing things alone or with just one or two people they know and trust. Introverts usually think and plan before they act or speak and sometimes like the idea of something better than the thing itself.
INtuiting
The second psychological preference indicates the way a person prefers to receive information. An intuiting person pays more attention to information patterns, impressions, and underlying meaning.
They learn by thinking things through and exploring the implications of new information. They mentally explore symbols, theories, and abstractions and remember ideas and concepts better than factual details.
Thinking
The third preference indicates the way a person prefers to make decisions. A thinking person makes decisions based on facts and data, striving for objectivity. They try to reach conclusions that are universally applicable and useful all the time in similar situations. They look for fundamental truths, underlying principles, and consistent practices without personal influence.
Judging
The final preference indicator refers to how a person deals with the outside world. For example, a person with a judging personality prefers a structured life, concrete plans, and firm decisions. They make step-by-step plans, keep to-do lists and schedules, and exercise control over their life and time.
These preferences make the INTJ highly independent, confident, and analytical. They emphasize facts and logic, prioritize information over emotion, and prefer structure and order but make their own rules.
An INTJ is innovative and creative, known for being a perfectionist who is seldom satisfied with the status quo. They are often critical and blunt and would rather be correct than popular, which limits their social success.
What Do ISTJ and INTJ Personalities Have in Common?
Superficially, ISTJ and INTJ personalities seem highly different. However, in fiction, the striking contrast between these two types is typified by ISTJ Sherlock Holmes and his nemesis INTJ Professor Moriarty.
Ironically, these two personality types seem very different, yet they are pretty similar. Here are some of the main things that ISTJ and INTJ personality types have in common:
1. Organized and Systematic
Both ISTJ and INTJ personalities are highly organized types. They tend to put work before play, plan and execute long-term plans and ambitious goals, and always follow through on their commitments.
These personality types prefer things to be structured and controlled, dislike chaos, and often avoid spontaneous activities.
2. Determined and Persistent
Their ability to remain organized and delay gratification allows both ISTJ and INTJ types to be incredibly persistent. They do not easily give up or change their minds, even when things become difficult.
This persistence enables them to accomplish incredibly ambitious goals over time.
3. Insensitive and (sometimes) Tactless
While neither ISTJ nor INTJ personalities deliberately try to be rude or inconsiderate, they often don’t work hard to avoid it. Instead, they tend to speak their minds without wasting time on small talk.
They also struggle to express their feelings, making it difficult for them to feel connected and close to the people in their lives.
6 Key Differences Between the ISTJ and INTJ Personalities
Despite these strong similarities in their behaviors and approaches to life, these personality types differ in values and interests. The most significant differences between ISTJ and INTJ personalities are:
1. Personality Type Frequency
ISTJ: 11-14% overall, INTJ: 2-4% overall
The ISTJ is the most common personality type in America, while the INTJ is one of the rarest. In fact, the INTJ personality type is the rarest among women, with just 1-3% of American women having this combination of preferences and characteristics.
2. Traditional vs. Unconventional
Traditional: ISTJ. The ISTJs love of order and routine extends to the world around them, where they are strongly motivated to uphold laws, habits, and traditions. Loyalty is an essential attribute of this personality type, and they work hard to show loyalty to friends and family, work and community, and society at large. They prefer to uphold and maintain the familiar and often resist change.
Unconventional: INTJ. The INTJ has an analytical mind that always sees how things could be better. They don’t respect authority or tradition for its own sake and are comfortable challenging the status quo when they think it could be improved. They are profoundly original thinkers and unconventional in their behavior.
3. Practical vs. Conceptual
Practical: ISTJ. An ISTJ is most concerned with the practical, immediate, tangible details of the world around them right now. They are not very interested in ideas or concepts that don’t affect the real world and learn best through their own lived experience.
They seek knowledge and information that can be applied to the present situation and are excellent practical problem-solvers.
Conceptual: INTJ. An INTJ is concerned with the concepts and ideas that underlie the present situation, and they tend to spend their time in abstract analysis and overlook concrete details.
This allows them to come up with very creative ideas, which may or may not work in the real world. They are symbolic thinkers who are often more interested in how things might be than how they really are.
4. Routine vs. Innovation
Routine: ISTJ. The ISTJ love of order and structure leads them to establish habits and routines. They tend to have a system or procedure for everything they do and often want everyone around them to follow their system. Therefore, they prefer to have plans, schedules, and lists and go by routines.
Innovation: INTJ. While the INTJ is not especially spontaneous, their habit of seeking improvement and perfection leads them to be creative and innovative. They constantly question habits and routines and seek new and better ways of doing things.
5. Grounded vs. Idealistic
Grounded: ISTJ. The practical, organized ISTJ is highly grounded. They are stable, reliable, predictable, and consistent. They are not prone to anxiety or self-doubt and are excellent caretakers and managers.
Idealistic: INTJ. The idealistic INTJ is often more interested in their imaginary world than the real one and can sometimes find the real world somewhat disappointing.
Their idealism is not dreaminess or wishfulness; instead, it often takes the form of perfectionism and excessive criticism. They may also get bored or disinterested in things that do not live up to their ideals.
6. Judgmental vs. Open-Minded
Judgmental: ISTJ. An ISTJ always sticks to their beliefs and values, even when wrong. They are very slow to accept change, criticism, or new ideas and often react by rejecting the ideas of others and sticking to their own judgments.
Their reluctance to accept things that are new and different often prompts them to seek out relationships with people who are like themselves.
Receptive: INTJ. An INTJ is always interested in new information, and their curiosity prompts them to actively seek out new opinions and new perspectives.
While they quickly reject ideas they think are illogical, and will readily adapt to new information and change course when they are wrong. They are not ashamed or embarrassed to be wrong unless they don’t correct themselves and adjust accordingly.
Final Thoughts on the ISTJ and INTJ Personalities
The ISTJ personality is the third most common in America, and chances are that you interact with this personality type regularly if you aren’t one yourself.
The logical, methodical, traditional ISTJ strongly values loyalty and consistency, and they make an excellent friend, partner, and family member. However, this personality type can be more challenging in the workplace because they tend to reject change and cling to old habits even when it’s time to evolve.
The INTJ type is much more scarce and behaves very differently. An ISTJ and INTJ are excellent partners: They have similar communication styles and respect each other’s intelligence and rationality. However, these types may never be able to become emotionally close and form a deeper bond due to their difficulties with understanding and expressing emotions.
Understanding personality types, including what they care about, how they learn, and how they behave, can help you build stronger relationships and communicate better with everyone in your life.
Check out our beginner’s guide to the 16 personalities to understand more about the science of personality types and how to apply this knowledge in your everyday life.
Finally, if you want to identify YOUR personality type, then take one of these 11 personality tests to better understand what makes you tick.
