Everyone has inherited qualities - like height, hair color, gender, and intelligence. What most people don't realize is that we all also have inherited preferences, and the combination of these inherited preferences largely determines adult identity.
Why should you learn about this? Because it takes a lot of energy to be someone you're not - and that's energy you need for your life.
There are 4 categories, and in each category there are 2 options. Remember, it's about preferences; nobody is all one or the other in any of the 4 categories. Also, in each category, the preference can be strong or mild. Try this simple test:
1.) When feeling drained, what do you need to do to re-charge? If sitting quietly and reading or writing energizes you more, then write down "I"; if walking and talking energizes you more, then write down "E".
2.) If you have a tendency to be sensible and practical, write down "S"; if you prefer possibilities and meanings, write down "N".
3.) If what you think about something is more important, write down "T"; if how you feel about something is more important, write down "F".
4.) The last is about schedules: if you want to explore and discover, write down "P"; if making a schedule and sticking to it is more important to you, write down "J".
I = Introverted, E= Extroverted, S = Sensible (or Sensation, as in physical sensation, as we will see), N = iNtuitive (because the I is already taken by Introverted), T = Thinker (or Tough-Minded), F = Feeling (or Friendly), P = Perceiving, J = Judging.
So, you now have you 4 letter code. (For example, I am an INTP.) The combinations automatically form into certain groups.
THE DIVIDING LINE
The main difference is between iNtuitive types and Sensible/Sensation types.
The S can stand for Sensible - as in Practical - which is generally a good thing, but can lead to certain problems; there's nothing "practical" about resisting The Evil. The S can also stand for Sensation - as in physical sensation. Sensation types are concrete in word and thought; abstract thought is thought of as something to be indulged in only after practical considerations are taken care of, and even then not too much. This group is further divided into 2 groups, depending on whether they like to stick to a schedule (SJ) or not (SP).
The SJ's are people who have a strong, fundamental faith or trust in the institutions of society: marriage, church, government, even any company that has been around a long time. Even though they are Sensation types, the Judging preference makes them resist physical pleasure, which causes the creation of "work-arounds" - sanctifying sex via religion, for example. They cannot choose whether to have these feelings or not, it is their identity. SJ's have a strong need to see themselves as good people. Can have a tendency to worry.
Pros: Bring stability to society, thereby making order possible.
Cons: Inherent trust in institutions and society causes failure to love the truth; generally not very interested in learning about themselves (like this subject, for example).
The SP's are free of that SJ reticence, and revel in physical sensations (esp. pleasure) in a way that the SJ's find both alluring and immoral. SP's who have a preference for Feeling are artists - composers and performers . SP's who prefer Thinking are promoters and sculptors.
Pros: Entertaining, fun, beautify and inspire with artful touch.
Cons: "In the moment" consciousness can make them unreliable; no inherent resistance to the Evil Culture.
The iNtuitives have an inherited preference for possibilities and meanings, whereas being practical or sensible is less important to them. This disdain for practicality can cause friction with the Sensation types. Abstract ideas are appealing to the iNtuitives; concrete words and thoughts seem "heavy"/restrictive. The iNtuitives are further divided into 2 groups, depending on whether they prefer Thinking (NT) or Feeling (NF).
The NT's are calm, rational, scientific and objective. Their relationship with their feelings - both physical and emotional - is conflicted, not because of morals (like the SJ's), but because the feelings are not rational. This affects their sex lives and emotional relationships in a way the Sensation types can't understand. The love of an NF is potentially life-changing for an NT.
Pros: Objectivity makes them very fair; remain calm in the face of problems; science improves the lives of all.
Cons: Other 3 types are not Rational, so NT's have a hard time respecting their rules or ideas; obsession with possibilities makes them forget practical considerations; can be ruthless.
The NF's are deeply caring and compassionate in a way that the other 3 types will never experience. Seek to actualize the self/become the ideal or "true" self. Make great counselors, healers, and therapists.
Pros: See the potential in everyone; love me, love you, love us, love them, love life, love love.
Cons: subconsciously project their essential goodness onto others (even when others don't deserve it); deep connection to spirit makes them forget sometimes that all non-NF humans have a long way to go before we get there; strong emphasis on love can make them susceptible to the "attack on standards".
The Fantastic 4
All 4 types bring good qualities to society; the problem lies in members of some groups trying to pretend they're in other groups (like when SJ's try to be scientists, for example). The comic and movie "The Fantastic 4" illlustrates this beautifully:
Ben Grimm is an SJ - gaurdian, protector, solid as a rock.
Johnny Storm is an SP - fun-loving, entertaining, always looking to "party", but in his element he is truly brilliant.
Reed Richards is an NT - the scientist who invents fantastic technology.
Sue Richards is an NF - caring and compassionate, these qualities are not valued in our society so that she feels invisible at times (but she has invisible power also).
All 4 types must work together to defeat the Dr. Dooms of our world - the Psychopaths.