In the early twentieth century Jung invented a way to look at and differentiate personalities based on preferences in how people perceive information from their environment and make decisions. If two people perceive and process the same information differently because of their brain differences, they are likely to have opposing views and attitudes, and misunderstandings are to be expected. Later, the Myers-Briggs Temperament Indicator (MBTI) was created, making the Jungian system more practical and useful.

Temperament consists of the traits you were born with. It differs from personality, which is a combination of your temperament and life experiences, although the two terms are often used interchangeably. Temperament is determined by your unique neurological characteristics, and it cannot be changed.

The system of differentiating temperaments has been around for a long time, has been studied extensively, and is widely used today. The beauty of this system, compared to other systems, is that it focuses on and is defined by opposing functions, for example, whether someone is an introvert or an extrovert. It does NOT predict exactly how a person will behave, but it does predict what drives certain types of people and how they are likely to perceive their environment compared with other people. I have personally found this system to be highly valuable and enlightening.
 

There are four opposing preferences which make sixteen possible temperament types:

Sensing versus iNtuition.
Your type of intelligence. This is the most important category. Sensing individuals are more likely to pay attention to facts and details and are observant of the here and now. Intuitors focus on meaningfulness of the facts, relationships between among the facts, and the possibilities of future events that can be imagined from these facts. They are introspective. Most people are Sensors.

Thinking versus Feeling.
Your preference when making value-based decisions. Thinkers value objectivity and logic, while Feelers base their decisions on their values and tend towards a personal approach. Thinkers are not smarter than Feelers, by the way, but sometimes appear to be!

Judging versus Perceiving.
A measure of your preference for structure Vs flexibility. Judgers prefer structure and organization and will want the problem-solving process to demonstrate closure. Perceivers prefer flexibility, adaptability and divergent thinking. They want to provide for unforeseen change and consider a variety of techniques.

Extrovert versus Introvert.
Extroverts get their energy from the environment and other people, while Introverts are energized by being alone with their thoughts and ideas.

It's actually a lot more complicated than the above, but that's the gist of it. Someone who has preferences for Introversion, iNtuition, Feeling and Perceiving is said to be an "INFP" type. On the surface, the test may not seem to make much sense. However, most people I know who have taken it (self included) have been really surprised at how accurately it predicted unusual aspects of their personalities, based only on the above four preferences.

I highly recommend that you take the online Keirsey Temperament Sorter test. It just takes five minutes.
 

The Four Basic Temperaments

In the book "Please Understand Me," David Keirsey and Marilyn Bates categorized the sixteen temperament types into four basic temperaments.

The Guardians SJ's (Sensing & Judging, 40-45% of the general population). These people remember all sorts of details and seem to get everything done with great satisfaction. They value tradition, seniority, and are inclined to look up to authority figures. They are thus described as the security seeking personality. The perfect Puritan.

The Artisan SP's (Sensing & Perceiving, 35-40% of the general population). Artisans remember detail and focus on the 'here and now' but are also sensation seekers and often have trouble in school or other situations where rote learning is required. Keirsey was convinced that hyperactivity classified in the 70's was normal SP behavior. SP kids are hands-on learners who often rebel if forced to sit too long in a desk. Most of our performers and artists are SPs, skilled craftsmen, and sports figures.

The Idealists NF's (iNtuition & Feeling, 8% of population): Idealists are abstract and conceptual. They are the identity seeking person, and are very conscience of good Vs. bad, right and wrong, moral and immoral. Idealists are the Intuitives who prefer to make value-based decisions rather than objective decisions. NP's (iNuition & Perceiving) lose detail and have murky memories, but are highly abstract, and are full of ideas and inner thoughts.

The Rationals NT's (iNtuition & Thinking, 7% of general population): The Intuitive Rationals are drawn to understand and manipulate the physical universe, and thus are natural born scientists and engineers. They are the knowledge seeking personality.

For some very readable descriptions on MBTI types, check out Psychological Type Profiles by Joe Butt and Marina Heiss. There are also descriptions of the types by at the Keirsey site, and I highly recommend the book "Please Understand Me", which has much more detailed descriptions of all the types, including how each type tends to behave as a child, a boss, and a mate.

There is no such thing as the perfect temperament. For example, an inborn preference for structure and organization apparently comes at the cost of reduced creativity. Both are necessary in the world, but our culture more often values the former. In the book "The Cerebral Code," William Calvin writes "We may range from satisfaction at getting something right (convergent thinking) to blue-sky divergent thinking; in those more creative moments, some of our cortical systems may be poised near the edge of chaos...chaos is controlled disorder!" The widely used Keirsey Temperament Sorter measures (among other things) a person's preference for more or less structure in life. The model's more creative temperament types are strongly associated with a preference for less structure.

Personally, I think our culture suffers from "SJ envy," a gift from the puritanical days. Many people, especially SJs, think SJ behavior is normal and anything else is some kind of maladjustment. SJs run our schools and many institutions. I believe many of the SPs, NJs, and NPs, 65% of the population, are struggling to be more like the SJs, an ultimately losing proposition. No wonder everyone is so stressed out. The fact that SJs are very bad at certain things is generally not known.

TAKE THE TEST YOURSELF AND FIND OUT WHAT KIND OF CHARACTERISTICS YOU HAVE

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