What are these other people thinking?

This question was inspired by a story a friend shared about a 10-day silent meditation he went to where aside from no talking, "silent" also meant no reading, no writing, no stimuli. With all this alone time (in the midst of other people) one of the things he got to thinking about was... what are these other people thinking??? And after the meditation was over, he had a chance to actually ask. And realized that he was really bad at guessing what other people are thinking... let alone what they are feeling! It made me wonder... how often do we choose to assume vs. ask? And in what circumstances do we assume vs. ask? How often do we actually know what other people are thinking? And how often do we give ourselves the permission to ask?