INTJ, here. We jump to conclusions and make ungrounded assumptions a lot. We read between the lines early on but we don't use Se to fill in the gaps with concrete information. We use Fi or for INFJ using Ti to make the assumption/conclusion make sense and seem absolute. Once we officially come to said conclusion, we're stubborn and rigid on being open-minded/optimistic to some extent. It's hard to accept facts and concrete proof when we're dead set.