I'm including "grip" material here because it's popular with so many people.  But I'm rather uncomfortable with it.  So before I give you any information about INFJs in the "grip," you have to hear my objections to it.

When Jung came up with his theories of Psychological Type, he was interested in examining the psyches of healthy personalities.  He once said that since Freud and other psychologists were focused on unhealthy people, it left the field wide open for him (Jung) to focus on healthy people.  And Isabel Briggs-Myers perpetuated this spirit when she developed the Myers-Briggs Type Indicator.  It was never intended to "psychoanalyze" people and discover what's wrong with them.  In fact, she hoped her instrument would contribute to world peace and prevent further wars in our world by helping people understand and cope with their differences in a healthy way.

And yet, this "grip" notion has taken hold of a lot of people, and they use it to "reverse engineer" type.  Really!  For instance, a guy told me how his ISFJ grandmother had been "in the grip" for years.  Digging a little further, his grandmother sounded like a perfectly normal Improviser.  But this notion of "grip" became a "filter" for this guy to label perfectly reasonable differences between himself and grandma.  He couldn't accept that her behaviors as an Improviser were healthy, so he rationalized her personality by claiming she was a Stabilizer "stuck in the grip" for years on end.  Of course, he has no frame of reference to what grandma looks like in a supposed well-functioning state, because he's only witnessed the one behavior pattern.  By the same token, my INFJ friend has been debating with someone who is convinced that Hugo Chavez (the Venezuelan Dictator) is an INFJ "in the grip."  Again, there is a reliance on pointing at unhealthy behaviors and using them to prove what someone's best-fit type is, which strikes me as the tail wagging the dog.

Taken to its logical extreme, certain historical characters have been characterized by the type community using this method of "reverse engineering."  A perfect example is Adolf Hitler*.  Many type experts claim that Hitler was probably _NFJ -- citing his LACK of Catalyst qualities to prove that's what he was, but suggesting that since Hitler was insane, this analysis doesn't have to make sense.  

I'm uncomfortable with that approach.  If every "exception" proves the rule, then the rule is useless.

I don't believe that "grip" behavior is as common or extreme as is sometimes implied.  And Dr. Linda Berens says that we can come under the "grip" of any function, so that leaves it with limited value as a Type compass.  "Grip" may simply be another term for what is to us bloody singlemindedness.  While it may be possible for you to learn about your own typical "grip" behaviors and their remedies, and perhaps even use this information to help determine your own best-fit type, I don't feel it's a wise or healthy tool for determining others' best-fit type, and I would caution you from using it in that way.  I don't think it's a reliable model, which is why I don't list it in that category, and I distrust those who employ it too widely.  The only way I entertain usefulness for any "grip" material is when it contradicts a person's normal behavior.  There must be a Dr. Jekyll to contrast with Mr. Hyde.  Otherwise, we should accept at face value that Mr. Hyde is the real person and not leave it to our imagination to construct what their "normal" personality must be.

The notion of the "grip" may hold value for self-analysis, but when used to analyze others it can become a weapon for condemning normal differences -- which is inappropriate and even unethical use of the material.  And we want to stay well away from that!

Okay, so what is this "grip" behavior I'm talking about?

Well, as I said already, we can get stuck in "the grip" of any function.  What that means is that we get trapped using a single function and experience everything single-mindedly through that one lens.  Introverted functions are especially easy to get trapped in.  INFJs sometimes get stuck in their iNtuition when they get riveted on an inner vision that ignores practicality -- such as wanting to buy the "perfect" Christmas present when it's Christmas Eve, or obsessing about a relationship that should have been perfect.  They can get stuck in introverted Thinking when they apply a particular model to everything they see (I've been known to do that with Type theory).  They might get stuck in their extraverted Feeling, helping others out to the detriment of themselves, or engaging in "runaway self-disclosure."  These behaviors all reflect possible "grip" experiences.

...And then there's the grip of the inferior.  When you fall into the grip of the inferior, you might find yourself saying things like, "I don't know what got into me," or "Something came over me," or "I wasn't myself."  Others may notice, remark on, or want an explanation for our odd behavior.  Our sense of the experience is, "Was that really me?"

More To come...

Usually, falling into the grip of the inferior happens when we are either over-using our dominant function and our system expresses a need for balance, or when we are at "low ebb" psychically.  Conditions that lower our conscious energy include illness, stress, alcohol/drugs, or fatigue -- and these all make us susceptible to "grip" behaviors.  We also want to beware of what 12-Step programs call "not taking care of yourself."  These behaviors include getting too hungry, too tired, or too lonely -- basically not taking proper care of ourselves.

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*Psychological Type expert and Jungian Dr. John Beebe makes an excellent case in the book Jungian Analysis, 2d edition, 1995 (pg. 329-330), that Hitler's preferences were for ISTJ.  And I quote

Hitler was originally probably an introverted sensation type, whose inferior extraverted intuition, carried by a hypomanic but inspiring anima (von Franz 1971), had led Germany in the 1930s to a miraculous economic recovery. On the verge of his starting World War II, however, encouraged by the fascination and lack of limit-setting of other world powers, Hitler's inflated, but unstable, extraverted intuition seemed to give over to its truly demonic shadow, an undermining introverted intuition that assumed the form of a distorted religious vision. Hitler's use of a falsified, "bedeviled" version of the old Germanic god Wotan (Burri 1978) to stir up archetypal support for his vengeful project of world domination and ethnic purification was like introducing a virus into the collective unconscious of the German people: he did succeed in producing a genuine religious disturbance, a caesura in the spiritual history of Europe, from which the West is still trying to recover (Lacoue-Labarthe 1990). Hitler's case, as no other, illustrates the dangerousness of the demonic function, that area of primitive compensations and uncanny possessions that is in all of us, but is an especial threat, through the collapse of the inferior function, to decompensating individuals.

It's logical for people to characterize Hitler as a dominant introverted intuitive, because functionally he was.  This is why a more-than-superficial understanding of type and Beebe's model are so important -- so that we do not conflate distorted functioning with normal functioning.  A riveting psychological analysis of Hitler written during World War II is available online here.

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