@Dylan phil,
I actually changed from an INTJ to an INTP after I took a philosophy course my senior year of college (1995 or 1996), and I've been an INTP on several repeat ones. I've always come out introverted, but I've always been very close to 50% on that one. The Intuitive, Thinking, and Perceiving are not very close, however.
The aspect of INTP that is a slam dunk for me is the teaching -- taking pains to explain complex concepts to people.
(Parenthetically, my wife is also an INTP, and we are afraid to ever take the test again in case we come out with different scores).