Some would say INTJ, ISTJ or INTP.
I don't believe he is IxTJ. Most of the time, he is passive with those around him, "in his own little world". When he talks with them he has a laid back style, not a Te style "sharpness". His monologues ar enot Te style either. There is not a concrete set of logic hammering away at you. I see rambling Ti-ness, and in many cases, when he seems more "J", it is inferior Fe lashing out. See below:
Thank God for the rain which has helped wash away the garbage and trash off the sidewalks. I'm workin' long hours now, six in the afternoon to six in the morning. Sometimes even eight in the morning, six days a week. Sometimes seven days a week. It's a long hustle but it keeps me real busy. I can take in three, three fifty a week. Sometimes even more when I do it off the meter. All the animals come out at night - whores, skunk pussies, buggers, queens, fairies, dopers, junkies, sick, venal. Someday a real rain will come and wash all this scum off the streets. I go all over. I take people to the Bronx, Brooklyn, I take 'em to Harlem. I don't care. Don't make no difference to me. It does to some. Some won't even take spooks. Don't make no difference to me.
Some would say the above is a Te style rant, but it is too rambling. I think it is inferior Fe, guiding unconsciously, and then breaking through openly, a Ti-exterior.
I first saw her at Palantine Campaign headquarters at 63rd and Broadway. She was wearing a white dress. She appeared like an angel. Out of this filthy mess, she is alone. They... cannot... touch... her.
Classic way that a Ti dom can go from 99% no feeling, to an inappropriate, unrequited, "love" for some constructed fantasy. I've been there myself in my younger days, and seen many INTP's on forums fall into the same kind of depressive "crush".
Next, Ti vs Te. I believe an IxTJ, while being introverted, does not feel themselves to be anything other than a model human being. Especially int he case of an unhealthy one like we have here, I would expect to see great conviction, a certain "high status" within their own chosen field, "quiet but confident". Travis Bickley on the other hand, is directionless (until his "transformation", which we will come to). The below quotes do not seem to me like someone who naturally orders their external environment:
Twelve hours of work and I still can't sleep. Damn. Days go on and on. They don't end.
Loneliness has followed me my whole life. Everywhere. In bars, in cars, sidewalks, stores, everywhere. There's no escape. I'm God's lonely man. June 8th. My life has taken another turn again. The days can go on with regularity over and over, one day indistinguishable from the next. A long continuous chain. Then suddenly, there is a change.
He also talks about his need to get "organazized" (wordplay) and even has this poster in his house.
The reason I believe ISTP above INTP is that his house is pretty clean and ordered, he does not seem "head in the clouds" or careless with his environment. An INTP can keep their house clean etc., but not in a depressed lonely state like him, only at a high functioning level, with a boot up their ass, a 9-5 job etc. I think an INTP in such a bad state as him, would have a messy physical environemnt, and spend a lot of time reading etc., neglecting their surroundings.
As for his "transformation, here is where my MBTI theory needs improvement.
It is guided by inferior Fe. The need to "reorganize" the world according to his strong principled (99% of which eh is laid back about - he does not have a clearly defined ideology - but there are some things that just disgust him, and which he despises so much he can't logically criticise them as a TJ would - this is why I believe it is inferior Fe).
BUT, it could EITHER be inferior Fe guiding a Ti-Si loop - causing him to fall back on the certainties of his past (which we don't know about) - OR it could be inferior Fe guiding a Ti-Ni loop - cuasing him to have, through Tert Ni, some delusional vision of the future.
I am inclined towards the Ti-Ni loop because he does not appear to be drawing on past experiences, or to be cuaght up in detail, but rather on an ill-defined vision of the future and of his former self.
I think ISTP's have a lot of this ability for self-transformation and great determination - and also for believing strongly in a vision of the future (INTP's will play with many possibilities but not see 1000% clearly, or believe strongly, in any of them) - I see it a lot in gym training programmes etc., and in a much less detailed "worldview" than INTP's have, i.e. more of a "broad vision" as Ni users have. This is what I see here, the "fantasy" world of an unhealthy Ni user:
June 29th. I gotta get in shape now. Too much sittin' is ruinin' my body. Too much abuse has gone on for too long. From now on, it will be fifty push-ups each morning, fifty pull-ups. There'll be no more pills, there'll be no more bad food, no more destroyers of my body. From now on, it will be total organization. Every muscle must be tight
Yeah. Huh? Huh? Huh? (I'm) faster than you, you fuckin' son of a...I saw you comin', you fuck, shit-heel. I'm standin' here. You make the move. You make the move. It's your move. [He draws his gun from his concealed forearm holster] Don't try it, you fucker. You talkin' to me? You talkin' to me? You talkin' to me? [He turns around to look behind him] Well, who the hell else are you talkin' to? You talkin' to me? Well, I'm the only one here. Who the fuck do you think you're talkin' to? Oh yeah? Huh? OK. [He whips out his gun again] Huh?
Listen you fuckers, you screwheads. Here's a man who would not take it anymore. Who would not let...Listen you fuckers, you screwheads. Here's a man who would not take it anymore. A man who stood up against the scum, the cunts, the dogs, the filth, the shit, here is someone who stood up. HERE IS --- [He draws his gun] You're dead.
Dear Father and Mother: July is the month I remember which brings not only your wedding anniversary but also Father's Day and Mother's birthday. I'm sorry I can't remember the exact dates, but I hope this card will take care of them all. I'm sorry again I cannot send you my address like I promised to last year. But the sensitive nature of my work for the government demands utmost secrecy. I know you will understand. I am healthy and well and making lots of money. I have been going with a girl for several months and I know you would be proud if you could see her. Her name is Betsy but I can tell you no more than that...I hope this card finds you all well as it does me. I hope no one has died. Don't worry about me. One day, they'll be a knock on the door and it'll be me. Love Travis.
I await thoughts of any fans of this movie