ISTPs are known for being down to earth, practical, and laid back. Rather than hearing a long winded explanation, they would much rather take action in the present and get results now.
You can always rely on an ISTP to fix something, create a solution, or troubleshoot a problem. These people generate solutions and implement them at an incredibly fast pace. Their analytical skills are top notch and when they are able to get their hands on something that catches their eye, they make sure to explore it all the way down to its core. Their dominant function is Introverted Thinking (Ti), and it is the source of their analytical prowess and troubleshooting abilities. With Ti, ISTPs are able to get to the root of the problem and make sense of it logically. They like to maintain their objectivity and let their rational self take the lead at all times; ISTPs and emotions do not mix well.
ISTPs live in the moment and like to take action in the present. Daily routines and boring methods are the best way to kill an ISTP on the inside. These people will work hard at something that actually interests them and like to find their own unique path in life. ISTPs have a risk taking air about them due to their auxiliary function: Extraverted Sensing (Se). Se relies on the 5 senses – sight, sound, touch, smell, and taste – and is the main source of their action oriented tendencies. They can even be led into dangerous career paths because living a life like everyone else would simply be too boring for these people. They are risk takers and thrive on action, however, keep in mind that these people are still introverts.
The dominant function of the ISTP is an introverted one and ISTPs need ample down time to recharge their batteries every now and then. ISTPs take in information from the world with their Se, then make sense of it and analyze the data with their Ti. These people are interested in the world around them and their curiosity knows no bounds. With the combination of Ti + Se, ISTPs perceive the outside world, analyze it, and then get to the core truth about what they have perceived. This combination is why ISTPs are so great at figuring out how things work. From there they can figure out how to improve or make tweaks to the current system.
Fields such as engineering where ISTPs can use their hands and work on something directly are places where they excel. They can absorb and memorize concrete facts with ease and also do well in fields such as accounting or mathematics. Their communication and social skills are areas where they may have trouble with, and they often have a hard time opening up to people. ISTPs will express themselves in as few words as they can but will make sure they get their point across. Even non verbal forms of expression can be their option of choice. A strong asset that ISTPs possess is their level headedness in high pressure situations; where others may get overwhelmed by their emotions, ISTPs will take their time and get the job done right.
Their tertiary function is Introverted Intuition (Ni), and their intuition is only there to support them in this lifetime. ISTPs get these feelings that they know they are right about something, even without actually going through the process and reaching the conclusion themselves. It gives them a quick glimpse of the future per se, and when properly developed it can become a very valuable asset in their toolbox. Ti + Se is the main combo for ISTPs, but Ni is the glue that holds everything together. Ni can also help when trying to piece together clues or hints, or interpret the hidden intentions of surrounding people. It can even make ISTPs suspicious of others and even avoidant of social interaction as a whole. Dreaded comfort zones and procrastination are also demons that these people will have no choice but to defeat.
Their inferior function is Extraverted Feeling (Fe), meaning that when it comes to sensing how are others are feeling they often have a tough time. Feelings in general are not the strong point of those with the ISTP personality type. They may even completely dismiss their own feelings and view it as a sign of weakness. As ISTPs develop their Fe they will become more and more comfortable with themselves and their own emotions, as well as become more tolerant of the emotional outbursts of others. Even from a young age Fe will show it’s rear end but it may not be as noticeable as it would be for other types.
Dominant function: Introverted Thinking (Ti)
Auxiliary function: Extraverted Sensing (Se)
Tertiary function: Introverted Intuition (Ni)
Inferior function: Extraverted Feeling (Fe)
There aren’t too many ISTP books on amazon but you may want to check out the one below. This book is recommend for those with ISTPs in their lives, as well as for further in depth self-learning for ISTPs themselves.