The function that distinguishes INFJs most from our Ni-dom partner, the INTJ, is our extroverted feeling function, or Fe.
Fe is our auxiliary, or secondary, function. It’s because of Fe that we’re able to walk into a room and pick up on the emotional energy without even talking to anyone. It’s how we know that a friend really needs to talk about something serious even if they’re parading around smiling and laughing. If you’re an INFJ, you’ve probably been told that you’re really easy to talk to, or maybe people just seem to open up to you really quickly and seemingly out of nowhere. That’s because Fe allows us to naturally adapt to social situations to make others feel more comfortable.
Often types that don’t possess extroverted feeling as a top function will judge a Fe-user for acting or being fake. It’s not that having Fe as a top function makes INFJs completely selfless individuals, we just naturally are more focused on the people we are around and the energy they give off than we are of our own feelings. This can, of course, cause problems when we are trying to separate what we are feeling internally from what we are feeling empathetically.
It’s usually during the teenage years that INFJs learn to develop, and also struggle with, Fe the most.