I've got a question about this whole subtype thing.

I know that socionics is not compatible with a theory of mixes between types, that is I/E, S/N etc are thought of as discrete rather than continuous, in order to assign different functions to different positions/roles.

But when it comes to subtypes, is there something in socionical theory that says (or requires) that the preference between functions 1 and 2 not be a continuous variable?

Are the subtypes fixed or do they represent ends in a spectra? And is subtype, like type, thought of as something that one is born with? Or can it actually be a learned behavior rather than a fundamental structure?

Allowing subtypes to be formed by environmental factors may actually be nature's way of making types more flexible. This might be beneficial in two ways. Firstly, it might allow for different "functional cultures" to be formed in different hunter-gatherer clans. Secondly, it might allow for a person to more easily adapt a sustainable role within the group, minimizing excessive friction with others.

Any thoughts? What do the mighty Russians say?