Originally Posted by
Gilly
Rationals thrive on stability and predictability. They expect that, once something is established, it will stay the same way. They attempt to form continuity in their perceptions and expect that this continuity is consistent with reality; if it isn't, then they attempt to enforce it.
Irrationals assume that the world is an unpredictable place. They are at ease with their perceptions changing, because they expect reality to change; they do not require any kind of established order or baseline in order for their perceptions to congeal and make sense to them, because they generally take things as they come and go. They base their ideas and organize their perceptions on the assumption that certain things will change, and, unlike rationals, are not frustrated or disappointed when their assumptions of stability or consistency are not met.
This differs by degrees and in emphasis from type to type, and even subtype to subtype,obviously, so it's helpful to gauge people's valued functions before attempting to see how they all fit together, but generally this is the idea.
When you're trying to type people, you can't just assume that these underlying psychological foundations will manifest consistently, because the transition from psychological organization to behavioral manifestation is simply not that consistent; there are too many variables between one level and the other. You have to examine people's behavior and perceive their overriding attitudes if you want to learn anything about their psychology.