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CHARTS below: All SARCASTIC Functions
POSTS modified from VERYWELLmind
ISTP = The CRAFTER (Review)
Strengths: action-oriented, enjoys new things, learns by experience, is logical, realistic & practical, self-confident & easy-going
Weaknesses: doesn’t like commitment, gets bored easily, hard to get to know, can be insensitive, is a risk-taker
DOMINANT = Ti
ISTP’s primary response is to spend a lo
t of time thinking about & dealing with information – in their own heads. This means that much of the time they don’t talk about that they’re into, so they’re considered ‘quiet’. It makes them hard to get to know, being focused on practical results rather than on feelings
It may seem like their approach to decision-making is haphazard, but actually their actions are based on careful observation & thought. They deal with the world rationally, their attention is on what’s useful. Because ISTPs mainly look at situations objectively, they miss important emotional considerations when making choices.
AUXILIARY = Se
As a support to the DOM, Se focuses on the present, taking things one day at a time. It can lead to avoiding long-term commitments, not wanting to think about future plans or possibilities.
ISTPs enjoy learning about how things work, like taking apart a mechanical device just to see how it was made. While they’re good at understanding abstract & theoretical information, they’re not particularly interested in it unless that info has some practical application.
TERTIARY = Ni
Less prominently, Ni in 3rd place operates indirectly, even unconsciously, – that ‘gut feeling’ they sometimes have. By synthesizing information gathered by DOM & AUX, they look for patterns, which may be responsible for sudden “aha” moments of insight, skipping 10 steps ahead to consider what may happen in the future. It allows ISTPs to turn 
abstract ideas into actions or come up with practical solutions
Because their internal world is very abstract & involves intuitive leaps it can be hard for ISTPs to fully explain how they reach certain conclusions.
INFERIOR = Fe
Here Fe is the least preferred, & while it tends to operate in the background, it can show up during times of stress. ISTPs often ignore their own femotions until things reach a boiling point, which can lead to lashing out in sudden inappropriate outbursts.
Fe is the ISTP’s humanitarian side, making them want to use their intelligence & creative problem-solving to help others & the world. Having Fe-INF means they start out life less aware of or equipped to deal with feelings than other types.
See: INTERNAL WORLD (scroll down)
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ISTJ = The INSPECTOR (Review)
Strengths : detail-oriented, logical and practical, observant, orderly & organized, present-focused, realistic
Weaknesses: insensitive, judgmental, subjective, tends to blame others
DOMINANT = Si
ISTJ‘s primary response is to focus on the present moment, taking in a lot of information about their surroundings. They also have vivid memories of the past, relying on those old experiences to form their expectations for the future.
ISTJs enjoy an orderly life & like to carefully plan things out well in advance, so they pay a lot of attention to details. When things are disorganized, they have trouble resting until they’ve set everything straight or the job is done.
AUXILIARY = Te
As a support to the DOM, Te encourages focus on details & objective data rather than abstract information or personal feelings. Because it’s the primary external function, it is usually the first thing others notice about ISTJs. Being logical & efficient, they enjoy looking for rational explanations for events, & appreciate info that has an immediate, practical application.
Te is the ISTJs main decision-making process & how they interact with the world around them. Te makes them loves efficiency & accomplishments, & can enjoy healthy competition if they think they can win. They’re more interested in moving forward than about finding the perfect solution.
TERTIARY = Fi
Less prominently, Fi in 3rd place leads to making choices using personal interpretations based on the ISTJ’s internal set of values, often called instinct. In spite of being sensitive to others’ feelings, they measure choices & actions using their own beliefs.
Their Te-AUX may want to make a decision using logic, only to have a strong intuition from Fi kick in – a warning system telling them something they’re planning is a bad idea & to trust the gut rath
er than just the facts.
Since Fi is internal, ISTJs need time to mull over details of a decision that will involve their values. This can help balance between their action-oriented analytical side & the part that considers the meaning behind things. So it would benefit them to strengthen this function.
INFERIOR = Ne
While generally a least preferred function, here Ne discourages truly radical or risky thought / behavior. INTJs are generally limited to ideas that don’t challenge their religious beliefs or core principles.
Many Si-DOM types spend a lot of down time playing games or working on puzzles. This lets them use creative thought & to look for possibilities in theoretically ‘safe’ ways. In most cases, Ne-INF indulgences doesn’t have negative consequences, as they’re generally self-contained.
Developing this function can lead to a more balanced personality.
See: INTERNAL WORLD (scroll down)
NEXT: ISFP & ISFJ
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