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Differentiating the Types via the Tertiary Function: ESTP and ISTP

Last article we discussed the idea that the tertiary function sets apart sister types. We saw this in action with the two NTP’s tertiary functions, Fe and Si. Now we’ll see the same principle with the two STP types’ tertiary functions Fe and Ni.

Fe is repressed in the ISTP. In the INTP this repression combined with their Ne/Si axis gives them (to quote Theodore Millon) an eccentric and intellectual expression and an alienated self-image. In the ISTP because of their Se/Ni axis their repressed Fe manifests as a more intense and direct “no-bullshit” approach to life. Take for example, the ISTP Steve Jobs. As Guy Kawasaki said, “if you’re a steve fan you say he knew how to cut through the bullshit. But if you’re not you say he lacked social graces.” And these social graces may be crippling for the ISTP. As ISTP Ron Paul said of his ISFJ son Rand Paul (a type whose Fe is far more developed): “It may well be that his approach will be far more succesful than mine ever was.”

In the ESTP, however, Fe is not repressed instead taking the tertiary position. Therefore, they aren’t not averse to diplomacy and negotiation that requires tact and social graces. Charm then is rightly praised as one of the ESTP’s greatest assets. Ben Affleck has been described by his wife as “charm personified when he wants to be.” But it’s a rakish and clever charm that contributes to the Antisocial personality in the ESTP (Antisocial meaning confrontational, independent, and non-conforming). And so the ESTP is very much like the ENTP in that his expression and approach may be interpreted as over-aggresive and be met with resentment.

Ni is repressed in the ESTP. This comes out in two ways that are relevant to the discussion of distinguishing sister types. The first is in their awe-inspiring courage. They don’t try to over-intellectualize or prepare for the future instead relying on improvisation and grace under pressure. Of course, this can go wrong for the ESTP as is the case with ESTP Douglas MacArthur in his invasion of China. To quote CelebrityTypes, “they may overestimate the scope of their … solutions.”

Many people associate the Se/Ni axis with an intense singular perspective and the Ne/Si axis with a flighty non-commital multifaceted perspective. I’d argue that this is somewhat erroneous. I think in Ni and Ne lies the difference in perspective, either multiple and flighty or singular and intense. This may seem trivial but it matters when Ni is repressed. As the ESTP Sasha Grey said: “If I only concentrated on one thing I would limit myself in life.” Which appears to be something that someone with Ne/Si would say but makes much more sense if you allow Ni and Ne to be the determining factor in this matter.

Ni takes the Tertiary position in the ISTP. While they can still be improvisational and reactive like the ESTP, they can intellectualize and sum up their vision of a goal before engaging the object. For example, it is said that Miyamoto Musashi delayed his duel with Sasaki Kojiro timing it so that he would be carried away with the tide afterwords, thereby escaping Kojiro’s angry supporters.

Since Ni is not repressed in the ISTP we do see an intense commitment to singular ideas and a rigorous perfection. Although the perfection is in part due to dominant Ti it is nevertheless intensely focused by tertiary Ni. And so with the repression of Fe and Ni’s difficulty expressing itself the ISTP developes a stoic silence, using only the words that are necessary. As was said of Jack Dorsey, when he speaks he makes every syllable count.


  • Barnes: Differentiating the Types via the Tertiary Function: ENTP and INTP Open Journal of Jungian Typology 2015
  • CelebrityTypes: Why Frank Ocean is ISFP CelebrityTypes 2012
  • Millon and Grossman: Moderating Severe Personality Disorders Wiley 2007
  • Pierce: Pierce Presents: ESTP CelebrityTypes 2014
  • Smith and Gregersen: Determining Function Axes, Part 1 CelebrityTypes 2012
  • Smith and Gregersen: Overview of Personality Styles CelebrityTypes 2015

Published in John Barnes