Good question..... I want to say I'm both just on different days in different situations.

I think my orginial personality type is the ISFJ, but I can see the INTJ aspects that have developed as I've gotten older. I had a life changing situation happen to me 8 years ago. I can see the pre and post effects on the personality.
"If you're going to do something tonight that you'll be be sorry for tomorrow morning, sleep late."
Henry Youngman.