Some thoughts on the last couple pages of discussion:
It sounds to me like the conversation is swirling around concepts (sometimes voiced, sometimes not) related to 1) nature vs. nurture, and 2) where individuals feel they have a locus of control. Since a lot of MB-types are being referenced, I'll try (probably poorly) to explain my thoughts within that framework.
Premise statements, which I hope can generally be considered "true" enough for what follows:
1. There are lots of different "types" of temperaments/people.
2. One can express varying degrees of a quality (E.g. Introversion-Extroversion is a continuum rather than a binary)
3. There exists some wiggle-room or fuzziness in a given quality in which a person can operate. (I.e. "I'm generally introverted, but that can modulate a little bit up or down with situation/context".)
4. A quick clarification/elaboration: when I say, "nature vs. nurture", I'm thinking about it as 'the individual' and 'their environment'. Specifically, I'm thinking about their
interrelatedness, which is to say that individuals have
at least some ability to change their environment, and environments have
at least some ability to change the individual.
Thought: How people think about nature vs. nurture or their individual locus of control seems to be closely related to 'temperament centrality'.
To demonstrate, let's first consider an extremely introverted individual. If the Introversion-Extroversion scale were 0 - 100, with 0 = 100% introverted and 100 = 100% extroverted, then this person might be, say, a 7. But that 7 is actually fuzzier (premise #3), so perhaps a range of 2-25 centering typically on 7. The issue is that most of the social environments this person encounters in contemporary society is probably centered around 30 - 70. This person, even at the extreme of their flexibility range, is still going to have a hard time adapting
to the environment. So the best strategy for this person is to focus on
control of their environment, focusing on the very peculiar, rare ones that allow them general comfort. A lot of effort is expended in adapting the
environment so that less effort is spent on adapting
themselves.
If we consider the opposite, someone squarely in the middle of the I-E axis, at say 53 (but with a range of 40 - 65), then the best strategy changes: Now, considering most social environments are 30 - 70, almost all environments encountered are within their flexibility range. The best strategy for this person is to focus on adapting themselves to the environment if possible.
Neither approach is wrong--in fact, both seek to minimize the overall costs (we could call this 'friction') that are inherent between the individual and their environment. There is a cost to crafting/selecting very specific environments. There is a cost (and a limit) to individual flexibility.
Another very basic way of framing this would be something like: "I'm not as happy as I could be. Do I figure out how to be a happier person (internal change), or do I need to change my environment/circumstances (external change)?"
I tend to align with @ego's views on personal growth, challenge, etc. - perhaps because I don't think I'm at the rarer ends of the various temperament spectra. I tend to think, as well, that with a bit of challenge/effort, I can grow/control my range (to some degree). For example, assuming I'm somewhere around ~40 (mild introvert) with a range of 30-55, I like the idea of challenging myself to increase the range to 25-60(!). To me, that seems well worth my time, because then I'll basically be comfortable in most (statistically) I-E environments (which: 1) opens up more opportunities, and 2) I will have further explored the boundaries of my true operating range--self-knowledge, yay!). I'm curious to hear if people think this is impossible/impractical, though.
Point being, where one sits on the idea of "FI first as The Move" has, I think, a lot of overlap with how one thinks about where their greatest control lies: in adapting themselves vs. in adapting their environment.
I'm sure I've probably completely missed the point, but those are my two cents.
