How are they different, really? I know the demonic function is in the 8th position and the inferior is in the 4th. For INTPs, that's Fi and Fe, respectively. But what I don't understand is how the role of the demonic function is different from the role of the inferior. How would demonic Fi play out in INTP? I've tried to find information about the demonic function without much luck.
Also I've read about the inferior function being the weakest function. But then, what about functions 5-8, are they supposedly weaker than the inferior? Is the demonic function the weakest of them all?
I hardly ever hear anything said about functions 5-8 from an MBTI perspective. One reason why I prefer socionics theory to MBTI theory is with the socionics theory, there is extensive descriptions of the 8 functions and what they do (Model A) . In MBTI, it seems like functions 5-8 are hardly ever talked about as if they're out somewhere in the netherworld. Yet we obviously use functions 5-8 on a daily basis. We have to use all 8 functions to survive as normal beings.