Personality is complex, combining both nature and nurture, and is influenced by many factors. Four basic personality temperaments were identified as far back as 450 B.C. Personality theory has its origins in the 1920s. Dr. Carl Jung, a Swiss psychiatrist, wrote about psychological types giving detailed descriptions of the basic mental functions and orientation to the outside world. In the early 1930s and 40s, the mother-daughter team of Isabel Myers and Katherine Briggs devised an instrument to make Dr. Carl Jung's theory of psychological types understandable and useful in people's everyday lives.¹ The Myers-Briggs Type Indicator (MBTI^®) is qualitative, not quantitative, sorting people into sixteen dichotomous categories, rather than indicating how strongly they exhibit the traits. It has been extensively researched, with a documented misclassification rate generally between 35 - 45%.²

       Decades later, in the 1970s, Dr. David Kiersey and Marilyn M. Bates were independently working on temperament theory, came across the MBTI©, and incorporated Myers-Briggs personality type ideas and terms into their work.³ They created a short inventory instrument called the Keirsey-Bates Temperament Sorter. Although Keirsey & Bates borrowed their terms from the Myers-Briggs system, it is important to remember that the Keirsey-Bates Temperament Sorter (KBTS) is just that -- a temperament sorter, not a personality type inventory. Temperament and personality type are two completely independent and separate theories, with an entirely different basis.⁴ The Keirsey-Bates Temperament Sorter focuses on the four historical temperaments, and the MBTI© focuses on eight dynamic mental functions. The KBTS should only be used to assist with identifying one's temperament, not one's four-letter personality type.

STRONG WORDS OF CAUTION:
USING ANY INVENTORY INSTRUMENT TO DETERMINE BEST-FIT TYPE

       There are many different temperament and personality type inventory instruments available through professional counselors, coaches and on the Internet. It is crucial to remember that none of these instruments can reliably identify your best-fit personality type. Even the most researched instrument (the MBTI©) correctly identifies all four letters of your best-fit type with at best 85%, and more usually between 50 - 75% validity.² What do I mean by this? Consider the targets below:

       Most inventories on the Internet probably fall under Category A. I know when I take them, they mistype me as INTJ sometimes, other times I come out an ENFJ or occasionally an ENFP (I am an ENFP). The Kiersey-Bates Temperament Sorter and the MBTI© fall under Category B - if you take them over and over again, they will assign you to the same type more often than not, but it may not be your true best-fit type. The MBTI has been shown to be slightly more valid (more likely to hit the "bull's-eye") than the KBTS, but both are frequently off the mark. The ability of the MBTI© to correctly identify all four letters of someone's type ranges from 53% to a maximum of 85% correlation with best-fit type.²

       So, which inventory instruments fall under Category C? NONE OF THEM. Why? We currently have no way to distinguish objectively most learned and value-driven behaviors from inborn ones, and Myers-Briggs personality is about your INBORN thinking and behavior patterns, not your acquired ones. Essentially, personality type identifies the basic operating system of your brain, regardless of what software you've installed since arriving on the planet.

       This means that those of you who try to take a short-cut, and attempt to identify your best-fit type solely using an inventory instrument, may very likely end up mistyped. The only valid way to determine your best-fit personality type is to use a multi-step process. In order to do this, you need a basic understanding of personality type theory -- what it is, and what it isn't -- and, you need to question seriously which of your behaviors are value-driven and/or learned rather than natural.

       Mistyping causes more confusion than not knowing your type at all, so please take some time and care when determining your best-fit type, and ask a professional for assistance if you get stuck or confused. As I showed you above, it is not a simple case of "take the test - this is your type". It is a multi-step process that requires you to look beneath layers of learned behavior. There's a checklist inventory on this site that will assist you with sorting through each letter; however, we first need to go through some basic concepts.

       Ready? Let's GO!