Why don’t the Interaction Styles match the Myers-Briggs letters in some parallel fashion?
The relationships between the two models were revealed by a matching of patterns derived from the different models independently. Each lens or model allows looking at the whole in different ways yet ignores the differences that might relate to other models. You can see the underlying logic when you remember that the MBTI code does not stand for a collection of traits that go with the four separate indices. Jung’s original work was based on eight holistic types, each characterized by a different mental process (see Appendix A). Fundamental to a holistic view is the understanding that trying to understand an organic whole by looking at the “parts” is an artificial distinction and the whole can never be fully understood through the parts.

Why do you say these styles are inborn?
Almost all of the related models suggest that these styles or types are inborn in some way, even if they focus on outer behavior. Ongoing studies have been conducted on the various “temperamental” traits that can be identified and tracked over time with physiological measures. Most notable of these are the extensive longitudinal studies of temperament traits by Stella Chess and Alexander Thomas. Their research extends over 50 years and tracks some of their subjects from as young as three months well into adulthood.

Robert Ornstein summarized research on these traits as three dimensions of temperament in Roots of the Self . In Ornstein’s view, temperament refers to the style of our behavior, not the content of our behavior. (This definition is different than David Keirsey’s definition of temperament.) Ornstein laid to rest the nature-nurture question by clearly stating that our behavior is determined by our nature, our past experiences, and the current context. Ornstein identified three main dimensions of temperament that have been measured physiologically and observed clinically:

• Cortical arousal
  How much external stimulation it takes to arouse the brain is seen as an indicator of how much internal activity is already going on. Some seem to need very little external stimulation and like to have a slower pace of input and more reflection time. Others seem to need a lot of activity and stimulation. He relates this directly to introversion and extraversion respectively.
• Regulation and organization of actions as in deliberation versus liberation
  Some people seem to need to structure and organize their actions and their thoughts. Others seem to need a maximum amount of freedom from boundaries. This dimension also relates to how freely emotions will be expressed or controlled. This continuum ranges from extreme planners who plan every detail, to extreme free spirits who abhor plans.
• Feeling tone as in approach versus withdrawal
  This dimension seems to have to do with which emotions are part of our make-up. Positive ones make us want to approach others and negative ones make us want to withdraw. The continuum here seems to go from extreme hyperactive elation to extreme immobilizing sadness.

These three dimensions are remarkably similar to the dimensions outlined by William Marston in the 1920s and the Social Style proponents.

How do you know these models are interrelated and the descriptions accurate?
I noticed that descriptions in the DiSC® and the Social Styles models had many similarities to the interaction style patterns we had been observing in relation to the sixteen types identified by the Myers-Briggs four letter code. Conceptual research led me to consult many original sources of descriptions. Most of these sources seemed to be describing patterns that also included aspects of Keirsey’s temperament patterns. When I filtered out temperament descriptors and looked at what seemed to be just the interaction patterns, I found characteristics that fit all four types (different temperaments) that shared each Interaction Style pattern.

From this research on other models and years of observations of the sixteen types as thematic wholes, themes were identified and descriptions drafted to describe each of the four interaction styles. To draft the self-portraits, we used the transcripts from the interviews used to develop the sixteen type descriptions in which four people of each type responded to the question, “What is it like to be you?” This provided the language of each style. The descriptions were validated by feedback from several people of each type who read the descriptions.