Another perspective on INTP I've been contemplating: if you're familiar with philosopher Walter Benjamin's theories on "aura" and "aurification", INTPs are people who are often in the process of de-aurifying things. It explains a lot: why we think so much, why we're so "negative" (people don't want their auras messed with), why we don't feel much, our decision-making (Pness)...
I was also thinking, and this is related, that we are probably the least worldly of the MBTI types in that all of our functions can be seen to be "anti-functions", in that they're often defined in the negative. To explain:
I: does not engage with other people
N: does not think in the present moment
T: does not feel other people
P: does not make decisions