Jung described a stack of four functions, and said that, in the typical case, the auxiliary (mostly conscious) served the dominant (the most conscious) and the tertiary (mostly unconscious) served the inferior (the most repressed).
This part from Psychological Types is what led Myers and others to make the auxiliary extroverted. If the aux is in every respect different, it suggests an opposite attitude (ie if dom is I, then aux is E).
Psychological Types said:
This absolute sovereignty always belongs, empirically, to one function alone, and can belong only to one function, since the equally independent intervention of another function would necessarily yield a different orientation, which would at least partially contradict the first. .... Naturally only those functions can appear as auxiliary whose nature is not opposed to the leading function. For instance, feeling can never act as the second function by the side of thinking, because its nature stands in too strong a contrast to thinking. Thinking, if it is to be real thinking and true to its own principle, must scrupulously exclude feeling. ... Experience shows that the secondary function is always one whose nature is different from, though not antagonistic to, the leading function : thus, for example, thinking, as primary function, can readily pair with intuition as auxiliary, or indeed equally well with sensation, but, as already observed, never with feeling. ... For all the types appearing in practice, the principle holds good that besides the conscious main function there is also a relatively unconscious, auxiliary function which is in every respect different from the nature of the main function. From these combinations well-known pictures arise, the practical intellect for instance paired with sensation, the speculative intellect breaking through [p. 516] with intuition, the artistic intuition which selects. and presents its images by means of feeling judgment, the philosophical intuition which, in league with a vigorous intellect, translates its vision into the sphere of comprehensible thought, and so forth.
The letter dichotomies are also based on Myer's idea that the auxiliary for an introvert determines their J/P preference also. Her book also groups people according to their dominant preference, which the J/P dichotomy is meant to indicate also. For example, she discusses both IxTPs as being Introverted Thinking types. So the difference between an ISTJ and ISTP is not simply J/P preferences, but what that indicates, which is that ISTJs are sensing types first and ISTPs are thinking types first, but that being introverts, each displays the other for their "face".
Remove the connection with functions and MBTI profiles don't make sense anymore.
Myers' function stack for a Ti-dom with an N-aux (for example) was Ti-Ne-Se-Fe, and the official MBTI folks have never endorsed the stack that flips the orientation of the tertiary. They've simply acknowledged that there is disagreement about that issue among MBTI theorists.
The tertiary is often listed without an attitude, true. I often suspect that no attitude is likely. Unless it's differentiated - which may happen with age as often suggested, who knows. Othewise I think it's probably fused with emotions, fantasies, memories - all the stuff Jung says aren't the functions themselves. If they get integrated, I suspect they are in service of the ego, so orientation may also be a moot point.
This is different from the inferior which is easier to detect an attitude for because it opposes the ego. When not differentiated, the tertiary is said to be fused to the inferior anyway.
So, I think the basis for giving the tertiary an opposite orientation to the inferior is based on this:
A grouping of the unconscious functions also takes place in accordance with the relationship of the conscious functions. Thus, for instance, an unconscious intuitive feeling attitude may correspond with a conscious practical intellect, whereby the function of feeling suffers a relatively stronger inhibition than intuition.
Aka An ST has an inferior NF attitude.
If the tertiary aligns with the inferior to form something of an opposite character to the ego and aux, then that suggests it would be opposite in every way to the inferior, just as the aux is with the dominant, or according to Myers' interpretation.
So the ST who is, say, Se ego with aux Ti would have an inferior Ni character with aux Fe.
I'm probably biased to that interpretation because I have trouble seeing another one in what Jung wrote (although what he wrote was vague).
Directed to the OP:
One reason I think people get confused is they think of functions as literal thought processes you "use" or even as skill sets, not as mentalities we identify with and display as personality. Myers notes this when she says a person often shows a preference when they can use either style, but may still have the ability for the non-preferred process when it's called for (ie Feelers can use logic). The inferior isnt an inability to use a thought process, it's more of a mentality that someone doesn't identify with, but which come out unconsciously.
That means cognitive function tests often aren't going to identify any typical function stack for someone. Rather, I notice that analyzing them shows they actually will indicate the same thing the dichotomies indicate, if you include the I/E and J/P preferences as wll.
For example, an IxTP type may find some Fi descriptions appealing, as they are Introverted Rationals, aka, it describes an IxxP preference. So they may show higher Fi than expected, but their Fe scoring is often predicably low.
Or an ISxJ type may identify with the Introverted Perceiving (Pi) qualities of Ni because it shows an IxxJ preference, not because they are even on their N/S preference. A low Ne score and higher Se score will often reveal that.
It can also happen where people identify with the same function but different attitude (ie N types tend to score themselves highly on both Ne and Ni).
Their lowest scores are often not the flip of the 4 function model for their type, but rather they reflect the opposite of their 4 preferred dichotomies.
This would defy the popular function stacks, but not the dichotomies, if you stop and think about what the person is actually identifying with (not always N/S or T/F, but also orientation and attitudes, which I/E and J/P represent). Given you can't always know what made someone identify with a statement, it becomes hard to untangle it, and without knowledge of the function dichotomies, it's not very helpful for typing.
I think there is one advantage in that in separating Si from Se or Fi from Fe, etc, it can peg a preference in someone who might otherwise be deterred by aspects of the function they dont relate to (ie I identify slightly more with Feeling than Thinking, but not when Feeling sounds like Fe. Then I will always choose the Thinyyking preference answer; however, cognitive function tests will always show me as preferring Fi a bit to Ti, although I will rate both highly).
Which, of course, is why it's not hard to understand that, despite the fact that people like Berens and Nardi have basically been peddling that stack for 15 years as if it's "the MBTI," the official MBTI folks who wear grown-up pants — and who accordingly share Isabel Myers' allegiance to data-based personality science — haven't endorsed it.
Nardi seems to be trying to bridge actual brain activity with the more psychospiritual ideas of Jung. IMO what Jung was talking about was more of a whole mentality, not specific processes. I think Nardi's ideas are interesting but he's too confident in putting them out there when there is not much to back up the patterns he supposedly detected (he didn't study many people at all).
I do have a few questions [MENTION=18736]reckful[/MENTION] - and maybe they're addressed in your other posts - but what of people who testing nearly 50/50 on certain dichotomies and may relate equally as much to both descriptions of the letter dichotomy?
Also, what about the matter of a large percentage of people testing as a different type months later?
It seems to me the focus on functions and order came out of these weak points in the test. People are looking to figure out their type when the dichotomies fail to clearly peg them consistently.
Personally, I only identified as a Feeling type after reading Jung and learning that Introverted Feeling is rational and doesn't look like Feeling or emotionality outwardly. The dichotomies put me smack in the middle of T/F.
Edit: to clarify, I don't accept the tandem junk either. I find that a gross misunderstanding of the tertiary and the inferior. I do think ideas like Lenore Thompson's (which had a similar concept to socionics) are pretty reasonable, because they assert that, say, an INTP having Ti-Ne preferences wouldn't be threatened by or suppress Ni and Te, and so they may show that mentality occasionally even if they much prefer Ti-Ne (I hesitate to say they use them, as then it sounds like skillsets). Basically, Ns will have stuff in common, Ts will have stuff in common, etc.
Fe would absolutely be inferior to them though, and arguably, Fi would even be less threatening and possibly more admissable, making them in no way a Ti-Fe type as if the two complement eachother and aren't opposing forces in their psychology with one unconscious and the other experienced as identity. A difference between an INTP and INTJ would also be that an INTP would find sensing less threatening than an INTJ, and the mbti dichotomy approach doesn't really touch on that. It does seem implied by Jung though and is noted when these new models talk about the tertiary. IMO its still a mistake to think of a tandem for the aux-tert because IF the tertiary is differentiated at all, then its in service of the ego not the aux and if not then its fused to the inferior.
