The other day I was sitting through the umpteenth Myers-Briggs workshop of my religious life. Though the presenter was pretty good, and was applying the types in interesting and pointed ways, I basically think such a thing is a tool of mystification and an excuse for going to purgatory, so my mind was wandering.
I started to think about metaphysics in general. Ancient people used to make metaphysical systems in an effort to understand the world around them: Heraclitus had the Flux, Plato had the Forms, and Aristotle had the Categories.
We late modern people, having given up on the mystical intelligibility of the macrocosm, and being succesfully turned in on ourselves (the so-called "turn to the subject") by Copernicus and Kant, look for metaphysical systems to explain our inner world. So we end up with the inner metaphysical system of Freud with his ego, super-ego, and id or Jung with his types and archetypes. From Jung we derive popular metaphysical systems like the Myers-Briggs Indicator.
It must be basic to our human nature to try to construct an ordered and logical system that makes sense of our experience. In a way it might be a way of imitating the creating act of God, who called the ordered and intelligible world out of the chaos of the original waters.
(By the way, I used to be an INFJ, but over the years I have become an INTJ, so you can cleverly tell me that my mind was wandering because I am of the NT temperament.)