Si - continuing from chat
We had some debate in chat about Si the other day. I couldn't continue there, takes too much time to work out the details. I'll continue here freely inspired by some of the themes that came up. I feel it's absolutely necessary to go into the finer distinctions, because otherwise these things will never be addressed.
"Sensation is about reality"
Yes and no. This is common sense and how we talk about sensation in everyday language. But as a psychic function and especially in the introverted attitude it's slightly different. A part of the general sensing experience comes from the subject, and Si focuses on this part. If Si is really well developed it can get to the point that reality falls into the background. Si is still sensation, but a sensation altered by the subject. You can compare this with Ti. "A thinking without facts".
"Is Si artistic?"
I would say it's often considered aesthetic. Si is usually not expressed so this is an exception anyway, but Si as an artistic or aesthetic function comes from the fact that it's introverted and focused on primordial sensations. It's as if the objects around as were impregnated by something genuine, psychic, primordial. An eye for the finer, deeper nuances. But Si in itself doesn't express anything, so the person has to develop some rational function in order to express Si.
"...but this sounds like intuition (Ni)"
Imo socionics has a bias were things are described from an extraverted standpoint. So as soon as an introverted / phenomenological view is introduced it sounds weird. But if we talk about introverted functions we have to use introverted language. It's impossible to understand Si if we just talk about cookies.
"Is Si abstract?"
Totally depends on what we mean by that. It's not abstract in the intuitive sense. Si is about what you hear, see, smell etc. But from an extraverted standpoint it could be considered abstract because it disregards the direct objective impact only focusing on the inner impression. But then the extravert forgets that there are hidden things also, even sensations can be hidden. But from the introverted standpoint it is very concrete and real, nothing is missing.
"Is Si practical?"
SLIs can obviously be practical. Si+Te is practical in more detailed work. Si makes the person interested in anything that stimulates inner impressions. SEIs can be interested in all kinds of practical work and materials but the quality of their work can be bad. I would consider Si useful in finer, more impressionistic work if combined with a rational function. But in my experience Se is more suited for the practical work people usually do.
Summary: Si is about sensing impressions evoked by the environment, "innervation phenomena" and the body and nervous processes as felt from within. It's a one-sided type of sensation where the object is more or less disregarded.