Interesting, thank you for notifying me of this. I remember seeing mention of the CT Pi temperament being related to the phlegmatic temperament awhile ago and that stood out to me as quite different from other models in which I’m well-versed; particularly Socionics.
In Socionics this would all seem to correlate most closely with the Ji temperament (or what they call the IJ temperament as the j and p is switched on introverts):
From Wikisocion on Ji temperament:
calm, balanced and inert
rigid but not very fast gait
may appear passive-aggressive
usually very stable mood
more reactive than active
little inclination to fidget during long periods of inactivity
IJs are both static and rational, so they see reality as mostly not changing and when it does, it's in abrupt "leaps" from one state to another. An IJ draws inner stability from a stable reality, especially as seen through his leading function. That makes him confident that things will probably remain as they are despite what he sees as minor disturbances; periods of clear upheaval are very disturbing and the individual is anxious that things will "settle down" one way or the other soon enough.
As introverts, IJs tend to be calm and relaxed about initiating relationships with other people, mostly assuming that others will take the initiative, but will be more inclined to try to make sure a relationship is maintained once established.
EP: IJs see EPs as unreliable, and too unpredictable in their impulses and initiatives.
EJ: IJs see EJs as pleasantly energetic and willing to take the initiative and get things going in a balanced, constant way.
IP: IJs see IPs as unreliable and unwilling to take any initiative, with too low levels of energy.”
These are the people I always associated with the phlegmatic temperament. They seem like turtles to me. They also tend to ramble on for long periods of time about philosophy. TiNe in that system would be the most philosophical and have a tendency to talk a lot.
The Pi lead (or IP as they call it) would more closely relate to the melancholic temperament, which makes sense to me as Jungian “ISTJ” is often said to be the pure melancholic type.
Here are the characteristics of Pi lead from Wikisocion:
finds it easy to spend long periods of time in no activity, or at very low levels of energy
movements are flexible, unhurried
little inclination towards fidgetiness when having to remain inactive for longer periods
IPs are both dynamic and irrational, so they see reality as in continuous, gradual, often imperceptible change. An IP is soothed by this, seeing reality through his leading function. This leads to a relaxed inclination to take things as they come and adapt to them.
As introverts, IPs tend to be relaxed and somewhat passive about initiating relationships with other people, mostly assuming that others will take the initiative.
EP: IPs see EPs as pleasantly energetic in an unpredictable and therefore not boring way, also able to take for granted variations in levels of energy in others.
EJ: IPs see EJs as annoyingly pushy and insistent in their initiatives; they may respect their energy levels but also wonder if they don't see that a lot of that energy is spent wastefully to no good purpose.
IJ: IPs see IJs as boring and too concerned with stability.”
This is the temperament I think best describes the melancholic temperament. I’m also pretty sure I’m not phlegmatic and although I’m not a pure type the melancholic (or lymphatic) is most suited to myself.
The sanguine/bilious/lymphatic/nervous system would be another interesting thing to discuss here as they have visual profiles as well. I’ve spent a lot of time matching the people in your database to those profiles and have found many of the Ji leads’ profiles align with nervous, the Pi leads align with lymphatic, the Pe (especially conscious Pe only) leads align with sanguine, and the Je leads align with bilious. This isn’t across the board, however, as some of the more unusual combinations (like Pe lead with conscious Pe and Pi only) seemed to align best with lymphatic, for example. Wish I knew how to post pictures and links to better explain myself here, but I hope you get the general idea of what I’m trying to convey.