How do so many people on here know other people's personality types?

I do both, but only to validate my guesses. I'm usually right, and always very close if I'm not.

 

There's a little MBTI bar under your profile name. It gives it away.

 

I type people I know mostly by function use. I ask myself "ok, what cognitive function are the using the most, then what do they back it up with" from that I determine their type. If that fails (and it does from time to time), I will go letter by letter. I am usually very accurate at pegging people's type.

 

A lot of people on MBTI forums type people they observe. I find other forums do this moreso than here. My guess is that generally speaking people are more often certain of other people's types than they are right about it.

What it does for people is to help simplify the complexity of others and make them seem more predictable. I find it is most difficult to type the people I know the best. If I barely know someone, it is easy to place them in a category based on a smaller sample of behavioral observations. It is easier to simplify who they are (not accurately) If I know the person well, there are two many contradictions and complexities to place them easily into categories.

 

I often try to type the people I encounter, but I am aware of the fact that although a person acts a certain way, I am not going to be able to trace every little aspect of their personality. I also think it really isn't up to me to label someone as a certain type, so I would prefer letting them take the test.

 

Well, first off, never expect to actually be right. Don't assume anything -- leave room for changes.

I type people because I know many people that are aware of their type. In other words, I can guess and they can tell me if I'm right or wrong. With that, I can see patterns between people of a confirmed type and use that later. Also, I/E can be very misleading, so I usually try to avoid that until I know the person. N/S can be as well, at times. But for the most part, it's a trial-and-error thing, and a bunch of guess work

I think it's kind of a fun exercise to type people in my head. It really puts you in-tune with those little things you wouldn't notice normally.

 

I type by archetype, then narrow down the temperaments. After many conversations.

I initially mistyped my friend victor as an ISTJ... Turns out he's just an ENTP who's damn good at his job.

 

They guess.