Ji vs Je: Declarative vs Imperative reasoning?

Oh, in case you don't watch the hobbit MIT CS professor too long, I should've included the precise terms and will now do so in the heading as well...

Declarative knowledge: What are things? About truths. When it digs for knowledge, it's seeking new things (to understand) not processes.
Imperative knowledge: How-to/procedural knowledge (What can you do with truth, i.e. declarative knowledge?) I think it explains the Ji-Je oscillation too, somewhat?

Like I said, I feel it's more the general difference between Introversion and Extraversion and may explain or at least be used to describe well the 'practicality' of Extraverted functions and the non-practicality of introverted functions in general.

Extraversion, in a way, is inherently about activity/practicality.

something ,

I'm constantly rethinking them. So far it feels right to associate the objective world with dynamism and the internal world with staticity. But I'm not yet sure how to think of the Perception functions in this way.

With the J functions, it's easier, because we know the proclivities of Je towards arranging the world and Ji towards sort of 'judging' it for acceptance or rejection using its own private sense of logic or truth. This makes it easier to see Je as something that is focussed on "moveable things." and Ji on immoveable things (truths).

My main issue with the J functions generally is that it's not obvious to me why Fi connects with Te and Fe with Ti. Even with this staticity/dynamism idea, I'm not sure why Te wouldn't be about "What can you do with Ti's declarative truth?" instead of "What can you do with Fi's declarative truth"? Same for Fe. 

It would seem that conducting the dynamism of collective feeling (Fe-ing) could use some static truths about the inherent value of things (Fi), no? Yet it doesn't work that way. 

It might be that the functions pair the way they do, not because of some kind of unworkability or natural repulsion between Fe-Fi in the same consciousness (or Te-Ti)--so that the psyche is forced to pick one and automatically forgo the other--but rather because evolution (or God) determined long ago that (a) we get only 4 functions each, (b) we get access to all S/N/F/T each, (c) we get access to all 4 EQs each! And that that's the only reason you get only one Feeling function, one Thinking function, one Intuitive function and one Sensing function. That for some reason, we need access to them this way to survive...and it's not because Fi has some sort of necessary connection to Te or Ti to Fe. 

I first thought that Extraverted Perception is a 'being moved' by the objective world (or moving in response to it to sort of avoid 'clashing') rather than moving it thing but it is obvious there's a very pro-active element to Pe as well. It just doesn't proceed or move things in terms of order. So now I think Pe is both. It's moving the world and being moved by it--a sort of dance, or perhaps play. So you have the objective world and the Pe mind/person each moving in relation to one another. It's still seeing the objective world in terms of motion but Pe relates to it in a more immediate (responsive?) way.

I think...

-I suppose you could say Pe behaves as if it is itself part of the moving things;

-While Je behaves as though moving through a field of moving things but not itself really part of the motion--sort of standing apart from it like a Judge/conductor/director (of the moving things).