Dominant Ni: The Doctor often comes to conclusions intuitively before he can back them up with Te logic. At times he comes to incorrect conclusions (monsters under the bed, robin hood is fake) and then aims to prove his theories unsuccessfully. He’s able to detect when people are lying without visible evidence and tends to understand people even though he can’t empathize with them. He has a narrow focus that develops around a large vision of how things should be. The Doctor absolutely hates surprises, doesn’t like to improvise and takes far longer to process new occurrences than the people around him (which is why he freaked out so much upon regeneration). He holds himself to high standards and wants to be a good person, but realizes that his own opinions are biased and so asks Clara whether he’s a good person. The Doctor wants there to be meaning in everything, including his face (when he first regenerates, he says he thinks that giving himself a lined face is a message to himself and tries to figure it out).
Auxiliary Te: The doctor doesn’t remember things that aren’t directly part of his vision, which is why he has trouble remembering names. He values efficiency and actually goes so far as to complement his enemies on it (“You’ve got to admire their efficiency”). On the rare occasion that he doesn’t understand something, he takes the situation apart and comes to logical conclusions about it. More than the previous three generations, he is decisive and acts regardless of how other people feel about something. He’s detached enough from his emotions to sacrifice people to save others and is much more blunt and argumentative in his speech patterns. He thinks out loud and gets annoyed when other people respond. He likes to be in control of his environment (to the point of merging that control into Clara’s love life). He plans ahead and gets frustrated when anyone interrupts those plans.
Tertiary Fi: The Doctor has strong opinions and moral beliefs about nearly everything and does not back down for anyone. He turns people he doesn’t like away and tends to be a bit rough with people in general. On the flip side, he’s incredibly tuned to his own emotions (though he detaches from them for decision making). The Doctor shows that he cares in a language that Clara cannot understand, using action rather than words (and those actions don’t always match up with the usual means for showing care). He tends to consider his own feelings before even remembering that other people’s exist. Despite his seeming hardness, the Doctor has a firm desire to protect others and genuinely wants to become better. Though he’s terrified and incredibly emotional on the inside, the Doctor does not like to talk about his feelings and absolutely despises invasions of his personal space (“No! I’m against the hugging!”).
Inferior Se: The Doctor is incredibly oversensitive to sensory details. He’s much more aware of his physical environment than the last three regenerations and anchors his beliefs in what he sees in physical reality. Often, sensory information overwhelms him, making him cross and difficult to be around. He revels in silence and when he first regenerates, obsesses over the fact that everything sounds and looks different. When he spends too much time traveling alone, he starts to lose touch with reality because he starts suppressing his Se (refer to Listen for details). He doesn’t really take care of his health (“I never bother with sleeping.”) and tends to be a bit reckless. Though he doesn’t like improvising, he’s capable of using his environment to his advantage at short notice when he has to.
There are loads of claims for twelve being an INTP, however, they’re all for for similar reasons that people claim Sherlock is an INTP. Twelve is an INTJ. He has a narrow focus and unlike the other recent regenerations, he doesn’t like to improvise. When he reaches conclusions, he stands by them much more firmly and he sets rules about the TARDIS. Besides, he always wants to have a plan before he acts –so not a P-type.