I've always thought a close family member of mine was INTJ. It never occured to me that he might be INFJ. But, the more I break down his personality, I'm thinking he might be INFJ.

Reasons to think INTJ:
-Can seem very logical
-Very good at math
-Fiercely competitive (does not like to be outdone by anyone)
-When talking about situations at work, seems to display Te ("I told this guy to get his head out of his butt and to start doing some critical thinking." "So and so is incompetent. I work circles around him. I could work 3 hours every morning, come back home and nap for the rest of the day, and I'd still be more productive than him.")
-Very quick witted with his responses.
-Doesn't take any crap from people who he sees as "opposition" - like in business negotiations.

Reasons to think INFJ:
-Very personable, funny, and polite (even charming?) in various social situations. It looks very much like Fe. Speaking to an elderly lady: "Yes ma'am. I appreciate the compliment. I've heard nothing but wonderful things about you from everyone and I'm seeing that the rumors are true. You're a wonderful lady."
-Sometimes allows himself to get "walked on" in relationships. Where the female is mean to him and he puts up with it.
-Very giving and caring about people he loves. If someone was in need, he would give that person his very last penny or the shirt off his back.
-Cries/gets emotional fairly easily. When someone has betrayed him or if he feels alone in the world.

Other information:

-Can be very vengeful. If someone does him wrong, he will get his revenge one way or another. Other than that, if you are on his good side, he is very loyal.
-Engineer by trade
-Extremely tough exterior to those who know him, but a "heart of gold" on the inside.

As I'm writing this, I have to lean towards INFJ or at least INxJ. Agree?