Hi Gerald, thanks for the excellent read! I downloaded the book, and it provides many insights on a detailed level. Something I am missing since I mostly read popular science books. I will read it! :)

"Exponentially this will automatically lead to the extinction of the NT trait within society."

Yep, I see your point here. I touched on this field by writing: "In the context of wealth, we must also talk about education. We know from developed countries that education leads to reduced reproduction."

Then we must ask which parts of society will be educated and which of these educated parts tend to reproduce less.

It brings us to a statement I wrote in my article "Change against Positive Feedback Loops": "First, a model is never complete — we will always find something we can add — variables and relations."

https://medium.com/predict/change-against-positive-feedback-loops-90889c360f17

And that is what we are basically doing here. However, it's the interesting point about systems thinking always to find the next thing to think about. So thanks for the nudge - and again, for the excellent read! :)

In general, when it comes to the MBTI, I am skeptical since I know its history of it, and it does not follow a scientific approach. However, professor Murphy points that out as well (p. 306):

"While the Myers–Briggs scheme is not free of criticism (see Box 18.1), the result from Do the Math is pretty convincing that the Myers–Briggs scheme is measuring something relevant."

In this context, I recommend reading Steven Reiss' book "Who am I?: 16 Basic Desires that Motivate Our Actions Define Our Personalities". There, Reiss shows the problems of the Myer-Briggs model. Of course, via his own model, not the Big Five. However, it's pretty impressive.