Clonester and Kalach: I figured I'd chime in on this...
introverted Sensing (Si) as the 8th function [INTJs/INFJs]
They usually ignore the past and may find they lack a storehouse of data. They may get stuck in impressions of how things were and resist change. When really stressed, they may waste time reviewing the impact of the past. Yet on occasion they tap into a universal knowing of how things have always been that, when woven into the context of their work and lives, can transform.extraverted Sensing (Se) as the 8th function [ENFPs/ENTPs]
When really stressed they may get caught up in a binge of being in the physical moment. This can result in excessively seeking stimulation or following the urge to sleep or do nothing. They zero in on isolated details, hastily acting on them in a chaotic disjointed way. Yet on occasion they can really tune in to what's tangible, using the physical world to transform and change.