called "four differing roles that people play in face-to-face interaction with one another." There are two Proactive Enterprising Roles: Initiators (expressive and directive): Field Marshal (ENTJ), Supervisor (ESTJ), Promoter (ESTP), Teacher (ENFJ)—Preemptive Contenders (attentive and directive): Mastermind (INTJ), Inspector (ISTJ), Crafter (ISTP), Counselor (INFJ)—Competitive There are two Reactive Inquiring Roles: Coworkers (expressive and informative): Inventor (ENTP), Provider (ESFJ), Performer (ESFP), Champion (ENFP)—Collaborative Responders (attentive and informative): Architect (INTP), Protector (ISFJ), Composer (ISFP), Healer (INFP)—Accommodative The roles were implied in the informing/directing factor introduced in Portraits of Temperament. In his 2010 follow-up book, Personology, "Coworkers" is renamed "Collaborators" and "Responders" is renamed "Accommodators". Temperaments and intelligence types The following table shows how the four rings relate to one another and to the various temperaments. Myers–Briggs types versus Keirsey's temperaments The type descriptions of Isabel Myers differ from the character descriptions of David Keirsey in several important ways: Myers primarily focused on how people think and feel; Keirsey focused more on behavior, which is directly observable. Myers's descriptions use a linear four-factor model; Keirsey's descriptions use a systems field theory model. Myers, following Jung's lead, emphasized the extraversion/introversion (expressive/attentive) dichotomy; Keirsey's model places greater importance on the sensing/intuition (concrete/abstract) dichotomy. Myers grouped types by 'function attitudes'; Keirsey, by temperament. Myers grouped types according to cognitive function: the 'thinking type' grouping for those with dominant thinking; the 'intuitive type' grouping for those with dominant intuition; the 'feeling type' grouping for those with dominant feeling; and the 'sensing type' grouping for those with dominant sensing. Keirsey's temperaments correlate with Myers' combinations of preferences: Guardians with sensing plus judging (SJ); Artisans with sensing plus perceiving (SP); Idealists with intuition plus feeling (NF); and Rationals with intuition plus thinking (NT). Myers paired ESTJs with ENTJs, ISFPs with INFPs, INTPs with ISTPs, and ENFJs with ESFJs because they share the same dominant function attitude. ESTJs and ENTJs are both extraverted thinkers, ISFPs and INFPs are both introverted feelers, INTPs and ISTPs are both introverted thinkers, and ENFJs and ESFJs are both extraverted feelers. Keirsey holds that these same groupings are very different from one another because they are of different temperaments. ESTJs are Guardians whereas ENTJs are Rationals; ISFPs are Artisans whereas INFPs are Idealists; INTPs are Rationals whereas ISTPs are Artisans; and ENFJs are Idealists whereas ESFJs are Guardians. Empirical validation In a 2001 peer-reviewed study published in the Journal of Career Assessment, data from the