ISFJ-T (Defender-Turbulent) Scientifically Explained

Do you know the ISFJ-T type?

This is one of the indicators that represents personality, and it greatly influences our behavior and way of thinking.

In this article, we will explain in detail what characteristics ISFJ-T people have, including aspects of health, work, and human relationships.

By understanding your own personality and that of those around you, it may lead to better communication and self-understanding.

Please try reading while comparing it with your own personality and that of your friends.

Once again, personality researcher and author of Villain Encyclopedia, Tokiwa (@etokiwa999), will provide the explanation.
※We have developed the HEXACO-JP Personality Assessment! It has more scientific basis than MBTI. Tap below for details.

Scientific Background of ISFJ-T (Defender・Turbulent Type)

Overview of MBTI

MBTI is a psychological theory that classifies personality into 16 types.

In the first place, MBTI is an abbreviation for Myers-Briggs Type Indicator.

MBTI classifies personality into 16 types by combining the following four indicators.

• Extraversion or Introversion
• Sensing or iNtuition
• Thinking or Feeling
• Judging or Perceiving

In other words, MBTI expresses one’s personality tendencies with four letters such as “ISTJ” or “ENFP”. There is a very famous similar one called 16personalities, but this is different from MBTI.

Overview of Big Five

One of the most influential trait theories in personality psychology is the “Big Five”.

The Big Five measures five traits: openness, conscientiousness, extraversion, agreeableness, and neuroticism.

Also, while 16personalities and MBTI use type classification (e.g., either extraverted or introverted), the Big Five evaluates traits with continuous numerical values (e.g., extraversion 3.5), which is a major difference.

Furthermore, it has been studied for a long time, has many research papers, and extensive research has been conducted in other fields such as academic ability, income, brain, and genetics. It can be said that the Big Five has relatively stronger scientific backing.

Correlation between MBTI, Big Five, and HEXACO

There is a correlation between the four indicators of MBTI and the five factors of the Big Five.

A representative study that showed this correlation is the paper “The relationship between the revised NEO-Personality Inventory and the Myers-Briggs Type Indicator“.

According to this paper, the correlation between MBTI and Big Five is as follows.

Also, in 16personalities, which was created based on MBTI and Big Five, the neuroticism of Big Five is called “identity“, and is classified as either Assertive or Turbulent.

On the far right is “HEXACO“, which is a relatively new personality assessment. It has been improved by adding one indicator “Honesty-Humility” to the Big Five.

Based on this correlation, this article will explain the 16personalities personality types in detail.

Since this is originally research from Big Five and HEXACO, if you want to know your personality more scientifically than MBTI or 16personalities, please try this HEXACO personality test.

What is ISFJ-T (Defender・Turbulent Type)?

ISFJ-T is a type with low extraversion (I), low openness (S), high agreeableness (F), high conscientiousness (J), and high neuroticism (T) in the Big Five. Characteristics:

• Strong empathy and compassion
• Perfectionism and self-criticism
• Sensitivity to others’ needs
• Stress from uncertainty
• Values tradition and stability

They are very sensitive to the needs of others and find joy in supporting them in practical ways. However, they often feel anxious about their own abilities and decisions. They pay attention to details and set high standards, but also have fears about not being able to achieve them.

In interpersonal relationships, they value harmony and stability, but are sensitive to criticism and rejection from others. They are prone to stress from change and uncertainty, but this also serves as a driving force for growth and improving their skills in supporting others.

擁護者(ISFJ型)：恋愛・相性・仕事・改善策など公式解説

Scientific Explanation of ISFJ-T (Protector/Cautious Type)

Easily Gets Along with People Who Have Both S and T Traits

People with ISTJ-T type tend to have low openness (S) and low agreeableness (T) in the Big Five. Therefore, they have high affinity with people who similarly possess S and T characteristics.

ISTJ-T individuals prefer realistic and logical thinking, and value facts and concrete information. Communication tends to be smoother with people who share similar values, and it’s easier to find common interests and topics.

However, it’s important to note that this is a general tendency and individual differences exist. Interactions with different types of people can also bring new perspectives and experiences.

For more details, please see this article.

友達の性格はどこが似てる？相性のいい人の探し方を解説

Psychotherapy May Increase Extroversion and Reduce Neurotic Tendencies

People with ISTJ-T type have characteristics of being introverted (I) and having high neurotic tendencies (-T). This indicates low extroversion and high neuroticism in the Big Five.

Through psychotherapy, ISTJ-T individuals may deepen their self-understanding and improve stress management skills. As a result, their extroversion may gradually increase, allowing them to feel more comfortable in social situations.

A reduction in neurotic tendencies can also be expected. By learning coping strategies for anxiety and stress, emotional stability will likely increase.

However, since individual personality traits are relatively stable, it’s important to accumulate small improvements rather than expecting dramatic changes.

For more details, please see this article.

心理療法で性格を変える！認知行動療法など論文で解説

Properly Maintains Social Distance for Infection Control

People with ISTJ-T type have introverted (I) personality traits and tend to have low extroversion in the Big Five. Therefore, they are likely able to relatively easily practice social distancing as an infection control measure.

ISTJ-T individuals generally do not prefer close contact with others and value their personal space. This characteristic naturally aligns with behaviors that help prevent infectious diseases.

Additionally, due to their tendency to be cautious and responsible, they are likely to understand the importance of social distancing and take it seriously.

However, it’s important to note that this is a general tendency and individual differences exist. It’s crucial to take appropriate actions according to the situation.

For more details, please see this article.

感染対策する人としない人の性格の違いを科学的に解説

Properly Performs Hand Washing and Other Infection Control Measures

People with ISTJ-T type have high conscientiousness (J) characteristics and tend to have high conscientiousness in the Big Five as well. This trait leads to reliably executing basic preventive measures such as hand washing for infection control.

ISTJ-T individuals tend to value rules and procedures and have a strong sense of responsibility. Therefore, they are likely to take infection prevention guidelines seriously and practice them thoroughly.

Additionally, due to their tendency to pay attention to details, they will likely be mindful of proper hand washing methods and frequency.

However, since they have high neurotic tendencies (-T), it’s also important to maintain balance so as not to worry excessively.

For more details, please see this article.

感染対策する人としない人の性格の違いを科学的に解説

Relatively Common Among Scientists; Even More Common with Lower Neurotic Tendencies

ISTJ-T type possesses personality traits that are relatively common among scientists. Being introverted (I), preferring logical thinking (T), and being planned and systematic (J) can be said to be suitable for scientific research.

In the Big Five, they tend to have low openness (S), low agreeableness (T), and high conscientiousness (J). These traits are helpful for detailed observation, data analysis, and systematic execution of research.

However, since ISTJ-T has high neurotic tendencies (-T), stress management may become a challenge. The ISTJ-A type with lower neurotic tendencies might be even more suited to being scientists.

To become a scientist, education, experience, and enthusiasm are important, not just these personality traits.

Please see this article for more details.

科学者に向いてる性格とは？適性や能力を論文で解説

Common among Writers/Editors, Artists/Creators, Counselors/Therapists

The introverted (I) trait of ISTJ-T type has affinity with professions such as writer/editor, artist/creator, and counselor/therapist. In the Big Five, they tend to have low extraversion.

These professions often require concentration and introspective thinking, which matches ISTJ-T characteristics. For example, as a writer or editor, they can utilize their ability to pay attention to details and construct text logically.

As an artist or creator, they have the potential to deeply pursue unique perspectives and expression methods.

As a counselor or therapist, they can demonstrate listening skills and analytical abilities, and approach client problems systematically.

However, these are general tendencies, and individual interests, abilities, and experience greatly influence actual career choices.

Please see this article for more details.

内向的な性格とは？具体的な強みを研究をもとに解説

Excessive Pursuit of Perfectionism

ISTJ-T type has high conscientiousness (J) characteristics, and tends to have high conscientiousness in the Big Five as well. This trait often manifests as excessive pursuit of perfectionism.

ISTJ-T people tend to set high standards and pay attention to details. This is advantageous for improving the quality of work and tasks, but can become problematic when taken too far.

For example, they may worry excessively about trivial mistakes or continue working until just before deadlines. They may also make overly demanding requirements of themselves and others.

Due to high neuroticism (-T), they may be prone to stress and anxiety from pursuing perfection too much.

It’s important to maintain balance and develop the flexibility to accept a “good enough” state.

Please see this article for more details.

完璧主義の性格は2種類？特徴や向き合い方を科学的に解説

Preferring Salty, Sour, and Greasy Foods Due to Stress

ISTJ-T type has high neuroticism (-T) characteristics, and tends to have high neuroticism in the Big Five as well. This trait may influence eating behavior during stress.

When feeling stressed, ISTJ-T people may tend to prefer salty, sour, and greasy foods. While these foods have the effect of temporarily improving mood, they can potentially lead to health problems in the long term.

For example, they might be more likely to reach for potato chips, pizza, or sour snacks.

This type of eating behavior is a form of stress coping, but it’s important to deal with stress in healthier ways. We recommend finding alternative stress relief methods such as exercise, meditation, or hobby time.

Please see this article for more details.

食事の栄養バランスを気をつける健康的な性格とは？論文解説

Health-Conscious, Preferring Vegetables, Dairy Products, and Nuts; Even More Health-Conscious When Neuroticism is Low

ISTJ-T type has high conscientiousness (J) characteristics, and tends to have high conscientiousness in the Big Five as well. This trait may manifest as interest in healthy eating habits.

Because ISTJ-T people are planful and highly responsible, they likely tend to make health-conscious food choices. They are likely to prefer nutritious foods such as vegetables, dairy products, and nuts.

These foods contain vitamins, minerals, and high-quality proteins and fats that help maintain overall health.

However, since ISTJ-T has high neuroticism (-T), they may worry excessively about health. ISTJ-A type with low neuroticism may be able to maintain healthy habits with a more relaxed attitude.

A balanced diet and moderate exercise are important for long-term health maintenance.

Please see this article for more details.

食事の栄養バランスを気をつける健康的な性格とは？論文解説

In the Case of Men, Tend to Become Husbands Who Get Cheated On

ISTJ-T type men have high neuroticism (-T) characteristics, which may affect their interpersonal relationships. In the Big Five, they tend to have high neuroticism and low extraversion.

Due to these personality traits, ISTJ-T men may struggle with expressing emotions or may find it difficult to notice their partner’s emotional needs. Additionally, due to their introverted nature, they may tend to avoid communication and social activities.

These factors may create emotional distance with their partner, potentially increasing the risk of infidelity as a result.

However, this is a general tendency and can vary greatly depending on individual values, behaviors, and the quality of relationships. Open communication and mutual understanding are important for building healthy relationships.

Please see this article for more details.

浮気・不倫をする旦那や妻の性格とは？調査方法や対策を解説

Tendency to hold Right-Wing Authoritarianism (RWA) and Social Dominance Orientation (SDO) ideologies

ISTJ-T types have characteristics of low openness (S) and low agreeableness (T), and these traits may be associated with specific political ideologies. Similar tendencies are observed in the Big Five as well.

Right-wing authoritarianism (RWA) ideology is associated with a tendency to value traditional values and existing authority. ISTJ-T individuals may find it easy to empathize with such ideologies because they tend to value order and rules.

Social dominance orientation (SDO) indicates a tendency to accept social hierarchies and inequality. The logical thinking and realistic aspects of ISTJ-T may have affinity with this way of thinking.

However, these are general tendencies and vary greatly depending on individual experiences, values, education, etc. Also, political beliefs are complex and multifaceted, and are not determined by a single personality trait alone.

Please see this article for more details.

偏見(バイアス)を持ちやすい性格とは？心理学の研究を解説

Practicing mindfulness reduces neuroticism

ISTJ-T types have characteristics of high neuroticism (-T), and tend to have high neuroticism in the Big Five as well. Practicing mindfulness may improve this trait.

Mindfulness refers to a state of mind that focuses awareness on the present moment and accepts it without judgment. This practice may be particularly beneficial for ISTJ-T individuals.

For example, when anxiety or worry is strong, through mindfulness, they may become able to recognize thought patterns and view situations more objectively.

Additionally, ISTJ-T’s planning ability and attention to detail may help in establishing mindfulness habits.

Through regular mindfulness practice, stress management abilities may improve, and overall mental well-being may be enhanced.

Please see this article for more details.

マインドフルネスでネガティブ思考を改善する方法とは？

Engages in emotion-focused coping

ISTJ-T types have characteristics of high neuroticism (-T), and tend to have high neuroticism in the Big Five as well. Therefore, they are likely to engage in emotion-focused coping as a stress management method.

Emotion-focused coping is a coping method that focuses on regulating emotions caused by stress. ISTJ-T individuals may try to cope with emotions caused by problems rather than the problems themselves.

For example, they might use relaxation techniques, confide their feelings to friends, or try to view stressful situations from different perspectives.

However, by also utilizing problem-focused coping while leveraging ISTJ-T’s logical thinking (T) and planning ability (J), they may be able to cope with stress more effectively.

A balanced approach is important for long-term stress management.

Attempts relatively calm risk management but holds biases toward risk due to high neuroticism

ISTJ-T types have characteristics of high conscientiousness (J) and high neuroticism (-T). Similar tendencies are seen in the Big Five, and these influence their approach to risk management.

ISTJ-T individuals tend to evaluate and manage risks relatively calmly due to their planning ability and attention to detail. Logical thinking (T) also helps with objective risk analysis.

However, high neuroticism (-T) may create biases toward risk. For example, they might overestimate risks or become fixated on worst-case scenarios.

This may lead to being overly cautious or missing opportunities.

Balanced risk management requires both objective data analysis and intuitive judgment. Also, listening to others’ opinions may provide opportunities to become aware of one’s own biases.

Please see this article for more details.

リスクマネジメントを冷静に行う性格とは？科学的に解説

Common in Japan’s Hokuriku and Chugoku regions

ISTJ-T types have characteristics of being introverted (I), thinking-type (T), and having high neuroticism (-T). These traits may have affinity with the culture and environment of Japan’s Hokuriku and Chugoku regions.

The Hokuriku and Chugoku regions are known as relatively peaceful areas that value tradition. The introverted nature of ISTJ-T may be well-suited to such calm environments.

Additionally, these regions tend to value diligence and responsibility, which may match the high conscientiousness (J) of ISTJ-T.

High neuroticism (-T) may be related to the climate of these regions (long winters and rainy seasons, etc.).

However, this is a general tendency, and there are individual differences and changes over time. Also, since various factors influence personality formation, it is not determined by regional characteristics alone.

For more details, please see this article.

「県民の性格診断」自分の性格が分からない人必見！論文解説

Schwartz’s Values: Security

ISTJ-T types tend to be conservative and value order (SJ), which is strongly connected to the value of “security” in Schwartz’s theory of values.

For ISTJ-T people, safety and stability are likely to be very important values. This includes not only personal safety but also safety at the social and national levels.

For example, ISTJ-T people may show the following tendencies:

• Strictly adhering to rules and laws
• Trying to minimize risks
• Valuing traditional values and customs
• Cherishing social order and harmony

However, placing too much emphasis on safety may lead to avoiding new experiences and changes. It’s important to maintain balance and take on new challenges appropriately.

Remember that individual values are complex and multifaceted, and other factors also have influence.

For more details, please see this article.

価値観と性格の違いとは？性格タイプごとの価値観を解説

Finally

ISTJ-T type people are cautious, have a strong sense of responsibility, and are good at planning. However, they also have characteristics of being prone to stress and anxiety.

People with this personality are good at paying attention to details and following rules. They also care about health and can properly implement infection prevention measures.

However, they may sometimes seek perfection too much or feel uncomfortable with change.

The tendencies introduced are originally from Big Five and HEXACO research, so if you want to understand your personality more scientifically than MBTI or 16personalities, please try this HEXACO personality test.