INFPs extroverted intuition supports Fi (idealized abstraction). ISFPs are a bit of a contradiction - they are sensors but aux Se supports Fi-dom. Explains why they are stereotypically artists - they feel a strong urge to manipulate physical environment to conform to an internal ideal.
Also explains the distinctive physical differences - IMO physical typing is easiest with INFPs and ISFPs. Fi-dom gives a very unique "feel" to the personality. There is the sense that they are self-assured but not arrogant or domineering. INFPs have a sloppy or indifferent appearance. ISFPs are very particular about their personal presentation because their physical self is a portable accessory in their idealized world.
I agree with the bit of a contradiction part....which is why I suggest they may lean on their tertiary function Ni a lot.
However, I, an INFP, love fashion & am not sloppy nor indifferent in my appearance. I know several ISFPs who are sloppy/indifferent, and some who aren't. Some, like my step-dad, like physical comfort first & foremost - it's function over form to them. My step-dad also is an artist (cartoonist), but he has little interest in the form of practical things, like furniture or clothes or even the appearance of food. He appreciates when someone else creates it, but has no interest in creating it himself.
So this can have a LOT to do with personal values & interests. I'm also a visual artist and have a good sense for space & color. NFs are often said to idealize beauty, and FiNe could certainly give the mindset to create beauty in the physical world & in every day life things such as dress. I'm personally not a fan of Keirsey's typing system for the reason that it is mostly behavioral.
There are many reasons people may display similar behaviors, which is why typing based on things like dress is a bad idea. Sure, there can be patterns, but patterns in thought will be a clearer indicator of type than patterns in behavior, IMO. If you find out WHY someone does something, then their reasoning process behind it can be a clue to their type.
Doesn't mean what he said wasn't true nor is he not an Fi type. "Every person is an exception to the rule".
Where did I say that? I said not understanding a concept does not make it untrue for someone. Many ISFPs would find the conceptual terms used in descriptions of Fi to be foreign, but that does not mean they don't use Fi. This is why many profiles try to strike a balance between describing a type in conceptual terms and giving real life illustrations as examples of the concept. The problem is when people take the illustrations as rules for type traits (ie. ISFPs are visual artists & INFPs are poets), and then you have a typing system that is a notch above astrology.
And yes, we're all individual snowflakes, isn't that speshial. Let's all sing kumbaya and cry now....
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