J's vs. P's

I read in a book about different personality types. J's like to make decisions. P's like to leave their options open as long as possible. It said that sometimes J's will hear decisions being made when P's are actually just thinking about their options. That happened to me once, where I said something and the guy I was talking to thought I had made a decision when I really hadn't. I find this personality theory explains a lot about how people communicate--or more often miscommunicate.