A couple of years before I took retirement from teaching at the University of Chicago in 2001, I had an experience that I never had before. A young Muslim - the son of successful South Asian parents living in the United States - lingered behind after the class. Then, as he was leaving the room, he turned around at the door and asked: "Mr Naim, why don't you pray?" I was taken aback. The subject of my or anyone's not praying - or for that matter of praying itself - had never come up in the class. I had, however, never joined the Friday prayers that were - and still are - held on campus regularly, which the two students apparently attended.